ASN RSS http://amnat.org/ Latest press releases and announcements from the ASN en-us Thu, 15 Feb 2018 06:00:00 GMT 60 ASN Awards for Support of Regional Meetings in Ecology, Evolution, and Behavior http://amnat.org/announcements/CallRegionalWkshp.html The American Society of Naturalists solicits proposals from organizers of regional meetings in the fields of ecology, evolution and behavior. The purpose of these small awards is to promote increased participation in regional meetings that fall along the research interests supported by the ASN and to use this support as a way of recruiting new membership to ASN. The awards typically provide subsidized registration for ASN members at these regional meetings. Please note that these awards are not intended to support workshops. Previous awardees have included meetings such as SEEPEG, SEEC, EVO-WIBO, and OE3C. Organizers of regional meetings should submit a brief proposal describing the research focus of the meeting for which funds are requested as well as details of the meeting such as anticipated number of participants, meeting venue and dates. Instructions:&nbsp;Proposals should include two components. One should clearly describe the (1) overlap of the regional meeting with ASN research interests, (2) extent that the support would reach out to new audiences to grow ASN&#39;s membership, and (3) potential size of the impact on ASN membership. The second component should include a brief budget justifying the amount requested and detailing how the funds will be used. To standardize the applications, there is a strict one-page limit (US Letter size paper, 1” margins, standard [e.g., Times] 12-point font, and no more than six lines per inch) for each component (i.e., 1 page for proposal, 1 page for budget description and use of funds). We anticipate funding 4-6 awards, typically valued at $2000-$3000. Please send proposals to the ASN Regional Society Liaison Committee Chair Steve Vamosi. <p>The American Society of Naturalists solicits proposals from organizers of regional meetings in the fields of ecology, evolution and behavior. The purpose of these small awards is to promote increased participation in regional meetings that fall along the research interests supported by the ASN and to use this support as a way of recruiting new membership to ASN. The awards typically provide subsidized registration for ASN members at these regional meetings. Please note that these awards are not intended to support workshops. Previous awardees have included meetings such as SEEPEG, SEEC, EVO-WIBO, and OE3C.</p> <p>Organizers of regional meetings should submit a brief proposal describing the research focus of the meeting for which funds are requested as well as details of the meeting such as anticipated number of participants, meeting venue and dates.</p> <p><strong>Instructions:</strong>&nbsp;Proposals should include two components. One should clearly describe the (1) overlap of the regional meeting with ASN research interests, (2) extent that the support would reach out to new audiences to grow ASN&#39;s membership, and (3) potential size of the impact on ASN membership. The second component should include a brief budget justifying the amount requested and detailing how the funds will be used. To standardize the applications, there is a strict one-page limit (US Letter size paper, 1&rdquo; margins, standard [e.g., Times] 12-point font, and no more than six lines per inch) for each component (i.e., 1 page for proposal, 1 page for budget description and use of funds). We anticipate funding 4-6 awards, typically valued at $2000-$3000.</p> <p><span style="line-height: 1.6em;">Please send proposals to the ASN Regional Society Liaison Committee Chair <a href="http://smvamosi@ucalgary.ca">Steve Vamosi.</a></span></p> Thu, 15 Feb 2018 06:00:00 GMT “Morph-specific patterns of reproductive senescence: connections to discrete reproductive strategies” http://amnat.org/an/newpapers/JuneGrunst.html The DOI will be https://dx.doi.org/10.1086/697377 Our results underscore the importance of social dynamics such as shared parental care in reproductive longevity Senescence, the gradual decline in performance with age, was once thought to be confined to humans inhabiting tame environments. In truth, senescence is a nearly universal property of life, manifest in an array of wild organisms. Substantial variation exists in senescence rates, with sex differences in senescence long appreciated. One hypothesis proposes that intense competition for mates, most commonly by males, induces a live-fast-die-young strategy, and rapid senescence. Alternatively, parental care may be associated with rapid senescence. Grunst et al. 2018 offer new insight into the influence of competition and parental care on senescence by studying the genetically-determined morphs of the white-throated sparrow (Zonotrichia albicollis). These morphs show discrete differences in behavioral traits that may affect rates of senescence. White morph birds are more aggressive and less parental than tan counterparts, and white males are promiscuous. In addition, social pairing is disassortative by morph, with white males pairing with tan females (W&nbsp;×&nbsp;T pairs), and tan males with white females (T&nbsp;×&nbsp;W pairs), almost exclusively. Social dynamics within pair types differ. T&nbsp;×&nbsp;W pairs practice biparental care, but in W&nbsp;×&nbsp;T pairs, care is female-biased. The researchers used data on sparrows breeding near Cranberry Lake Biological Station in New York’s Adirondack Mountains. Drs.&nbsp;Elaina Tuttle and Rusty Gonser have studied this population since 1991. Aging white males displayed faster reproductive senescence than tan counterparts, but lived longer. Thus, faster reproductive senescence in white males likely reflects difficulty sustaining a competitive reproductive strategy with age, rather than physiological costs of competitiveness. Tan females exhibited earlier reproductive senescence than white females, and were short-lived, perhaps reflecting challenges of unsupported motherhood. Biparental care may also help older tan males and white females sustain reproductive performance. Thus, social dynamics may play an underappreciated role in determining patterns of senescence. Abstract How reproductive strategies contribute to patterns of senescence in natural populations remains contentious. We studied reproductive senescence in the dimorphic white-throated sparrow, an excellent species for exploring this issue. Within both sexes the morphs use distinct reproductive strategies, and disassortative pairing by morph results in pair types with distinct parental systems. White morph birds are more colorful and aggressive than tan counterparts, and white males compete for extra-pair matings whereas tan males are more parental. Tan males and white females share parental care equally, whereas white males provide little parental support to tan females. We found morph-specific patterns of reproductive senescence in both sexes. White males exhibited greater reproductive senescence than tan males. This result likely reflects the difficulty of sustaining a highly competitive reproductive strategy as aging progresses, rather than high physiological costs of competitiveness, since white males were also long-lived. Moreover, morph was not consistently related to reproductive senescence across the sexes, arguing against especially high costs of the traits associated with white morph identity. Rather, tan females exhibited earlier reproductive senescence than white females, and were short-lived, perhaps reflecting the challenges of unsupported motherhood. Results underscore the importance of social dynamics in determining patterns of reproductive senescence. More forthcoming papers &raquo; <p><i>The DOI will be https://dx.doi.org/10.1086/697377 </i></p> <!-- <p><b><i><a href="https://dx.doi.org/10.1086/697377">Read&nbsp;the&nbsp;Article</a> </i></b></p> --> <p><b>Our results underscore the importance of social dynamics such as shared parental care in reproductive longevity </b></p><p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">S</span>enescence, the gradual decline in performance with age, was once thought to be confined to humans inhabiting tame environments. In truth, senescence is a nearly universal property of life, manifest in an array of wild organisms. Substantial variation exists in senescence rates, with sex differences in senescence long appreciated. One hypothesis proposes that intense competition for mates, most commonly by males, induces a live-fast-die-young strategy, and rapid senescence. Alternatively, parental care may be associated with rapid senescence. Grunst et al. 2018 offer new insight into the influence of competition and parental care on senescence by studying the genetically-determined morphs of the white-throated sparrow (<i>Zonotrichia albicollis</i>). These morphs show discrete differences in behavioral traits that may affect rates of senescence. White morph birds are more aggressive and less parental than tan counterparts, and white males are promiscuous. In addition, social pairing is disassortative by morph, with white males pairing with tan females (W&nbsp;×&nbsp;T pairs), and tan males with white females (T&nbsp;×&nbsp;W pairs), almost exclusively. Social dynamics within pair types differ. T&nbsp;×&nbsp;W pairs practice biparental care, but in W&nbsp;×&nbsp;T pairs, care is female-biased. The researchers used data on sparrows breeding near Cranberry Lake Biological Station in New York’s Adirondack Mountains. Drs.&nbsp;Elaina Tuttle and Rusty Gonser have studied this population since 1991. Aging white males displayed faster reproductive senescence than tan counterparts, but lived longer. Thus, faster reproductive senescence in white males likely reflects difficulty sustaining a competitive reproductive strategy with age, rather than physiological costs of competitiveness. Tan females exhibited earlier reproductive senescence than white females, and were short-lived, perhaps reflecting challenges of unsupported motherhood. Biparental care may also help older tan males and white females sustain reproductive performance. Thus, social dynamics may play an underappreciated role in determining patterns of senescence. </p> <hr /><h3>Abstract</h3> <p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">H</span>ow reproductive strategies contribute to patterns of senescence in natural populations remains contentious. We studied reproductive senescence in the dimorphic white-throated sparrow, an excellent species for exploring this issue. Within both sexes the morphs use distinct reproductive strategies, and disassortative pairing by morph results in pair types with distinct parental systems. White morph birds are more colorful and aggressive than tan counterparts, and white males compete for extra-pair matings whereas tan males are more parental. Tan males and white females share parental care equally, whereas white males provide little parental support to tan females. We found morph-specific patterns of reproductive senescence in both sexes. White males exhibited greater reproductive senescence than tan males. This result likely reflects the difficulty of sustaining a highly competitive reproductive strategy as aging progresses, rather than high physiological costs of competitiveness, since white males were also long-lived. Moreover, morph was not consistently related to reproductive senescence across the sexes, arguing against especially high costs of the traits associated with white morph identity. Rather, tan females exhibited earlier reproductive senescence than white females, and were short-lived, perhaps reflecting the challenges of unsupported motherhood. Results underscore the importance of social dynamics in determining patterns of reproductive senescence. </p> <div style="float: right;"><a href="http://www.amnat.org/an/newpapers.html"> <span style="font-size: large; font-family: Georgia;"><i>More forthcoming papers</i> &raquo;</span></a></div> Tue, 13 Feb 2018 06:00:00 GMT “The influence of climatic variability on morphological integration, evolutionary rates, and disparity in the Carnivora” http://amnat.org/an/newpapers/JuneConith.html The DOI will be https://dx.doi.org/10.1086/697376 Current patterns of biodiversity are unevenly distributed spatially and temporally across the globe. Broadly speaking, biodiversity reaches its peak in tropical regions and decreases towards the poles. Dobzhansky, and later Fischer, first attempted to untangle the likely causes of latitudinal gradients in organismal biodiversity, and suggested seasonal and annual differences in climate could be important. Indeed, regions with the most variable climatic conditions typically contain habitats with the fewest niches, largest fluctuations in food availability, lowest primary productivity, and lowest species diversity. However, the extent to which climatic variability has influenced morphological evolution has yet to be tested. Understanding how climate affects the course of morphological evolution is vital to understanding current geographical variation in species distribution and modeling the potential for phenotypic responses to climatic change. Here, Andrew J. Conith, Molly A. Meagher, and Elizabeth R. Dumont investigate whether climatic variability is associated with three different components of morphological evolution: phenotypic integration, the rate of morphological evolution, and disparity (morphological diversity). They extract climatic variability data from within species range maps, and gather landmark data from the jaws of three large families of carnivorans, Canidae, Felidae, and Mustelidae. They find a negative relationship between climatic variability and phenotypic integration for canids and felids. For both clades, relatively variable climates were associated with low phenotypic integration. They also find a negative association between climatic variability and both disparity and rates of morphological evolution in canids and mustelids. Taken together, this suggests that those taxa in more variable regions (e.g., temperate, montane) may be more evolvable and thus more able to respond to fluctuating environmental conditions over time. Abstract Biodiversity is unevenly distributed in space and time. One possible explanation is the influence of climate on the ecology, evolution, and morphology of taxa. Here we investigated the link between climatic variability and phenotypic integration, rates of morphological evolution, and disparity (morphological diversity) in three carnivoran clades (Canidae, Felidae, Mustelidae). We gathered landmark data from the lower jaw and extracted current temperature and precipitation data from range maps. We found a significant negative relationship between climatic variability and integration for canids and felids. Among canids variability in temperature was the key climatic variable, while in felids it was a combination of variability in temperature and precipitation. In both cases, relatively variable climates were associated with low phenotypic integration. We also found evidence for a negative association between climatic variability and both disparity and rates of morphological evolution in canids and mustelids. Selection can drive the evolution of jaw shape along lines of least resistance defined by patterns of integration, and this study suggests that climate may be a predictor of phenotypic integration. As a result, taxa in more variable regions (e.g., temperate, montane) may be more evolvable and more able to respond to fluctuating environmental conditions over a period of generations. More forthcoming papers &raquo; <p><i>The DOI will be https://dx.doi.org/10.1086/697376 </i></p> <!-- <p><b><i><a href="https://dx.doi.org/10.1086/697376">Read&nbsp;the&nbsp;Article</a> </i></b></p> --><p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">C</span>urrent patterns of biodiversity are unevenly distributed spatially and temporally across the globe. Broadly speaking, biodiversity reaches its peak in tropical regions and decreases towards the poles. Dobzhansky, and later Fischer, first attempted to untangle the likely causes of latitudinal gradients in organismal biodiversity, and suggested seasonal and annual differences in climate could be important. Indeed, regions with the most variable climatic conditions typically contain habitats with the fewest niches, largest fluctuations in food availability, lowest primary productivity, and lowest species diversity. However, the extent to which climatic variability has influenced morphological evolution has yet to be tested. Understanding how climate affects the course of morphological evolution is vital to understanding current geographical variation in species distribution and modeling the potential for phenotypic responses to climatic change. </p><p>Here, Andrew J. Conith, Molly A. Meagher, and Elizabeth R. Dumont investigate whether climatic variability is associated with three different components of morphological evolution: phenotypic integration, the rate of morphological evolution, and disparity (morphological diversity). They extract climatic variability data from within species range maps, and gather landmark data from the jaws of three large families of carnivorans, Canidae, Felidae, and Mustelidae. </p><p>They find a negative relationship between climatic variability and phenotypic integration for canids and felids. For both clades, relatively variable climates were associated with low phenotypic integration. They also find a negative association between climatic variability and both disparity and rates of morphological evolution in canids and mustelids. Taken together, this suggests that those taxa in more variable regions (e.g., temperate, montane) may be more evolvable and thus more able to respond to fluctuating environmental conditions over time. </p> <hr /> <h3>Abstract</h3> <p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">B</span>iodiversity is unevenly distributed in space and time. One possible explanation is the influence of climate on the ecology, evolution, and morphology of taxa. Here we investigated the link between climatic variability and phenotypic integration, rates of morphological evolution, and disparity (morphological diversity) in three carnivoran clades (Canidae, Felidae, Mustelidae). We gathered landmark data from the lower jaw and extracted current temperature and precipitation data from range maps. We found a significant negative relationship between climatic variability and integration for canids and felids. Among canids variability in temperature was the key climatic variable, while in felids it was a combination of variability in temperature and precipitation. In both cases, relatively variable climates were associated with low phenotypic integration. We also found evidence for a negative association between climatic variability and both disparity and rates of morphological evolution in canids and mustelids. Selection can drive the evolution of jaw shape along lines of least resistance defined by patterns of integration, and this study suggests that climate may be a predictor of phenotypic integration. As a result, taxa in more variable regions (e.g., temperate, montane) may be more evolvable and more able to respond to fluctuating environmental conditions over a period of generations. </p> <div style="float: right;"><a href="http://www.amnat.org/an/newpapers.html"> <span style="font-size: large; font-family: Georgia;"><i>More forthcoming papers</i> &raquo;</span></a></div> Tue, 13 Feb 2018 06:00:00 GMT ASN Election http://amnat.org/announcements/ASNElections.html The ASN 2018 Elections are underway for tha offices of President, Vice President, and Secretary. The election website randomizes the order for each person voting, but the names below are in alphabetical order.The PRESIDENT leads the ASN Executive Council and selects the membership of the award and officer nomination committees. The President selects the President’s Award for the “best” paper in The American Naturalist in the past year, gives the ASN Presidential Address and presents the Society’s awards at the annual meeting, and represents the ASN in multiple other ways through the year. The President serves on the Executive Council for five years, including one year as President-Elect and three years as a Past-President. Susan Kalisz, University of Tennessee, Knoxville My interests are in evolutionary biology and ecology.&nbsp; My research focuses on the evolution of&nbsp; mating system and the role of mating system shifts in speciation in plants, mutualism and mutualism disruption by invasive species, and demographic and population modeling. These research projects intersect in my interest in deeper questions about the effects of human’s actions across the globe in altering the tempo and mode of evolution, and the sustainability and conservation of biodiversity. I received my Bachelor’s of Science degree from the University of Michigan, where I was inspired by the dazzling diversity, forms and functions of plants. I received my Masters and PhD degrees from the University of Chicago, where I learned how the interaction of ecology and evolutionary forces shaped those dazzling forms. Directly from Chicago, I took a faculty position at Michigan State University where I became a tenured associate professor, then moved to the University of Pittsburgh where I became a full professor in 2001. I joined the University of Tennessee, Knoxville (UTK) in 2015 as Professor and Head of the Department of Ecology and Evolutionary Biology. I was invited to serve as program director in the Division of Environmental Biology at the National Science Foundation (2009-2010) and I currently serve on the Faculty of 1000. I co-led two National Evolution Synthesis Center (NESCent) Working Groups, and served as a member of the NSF microMORPH: Microevolutionary Molecular and Organismic Research in Plant History Research Coordination Network Steering Committee 2010-2017, the Botanical Society of America Merit Awards Committee 2011-2014, and as associate editor for the journals Evolution, Journal of Ecology and The American Naturalist. As a graduate student, I joined ASN (loved to discuss graphs with unlabeled axes), and while serving as one of three Editors for The American Naturalist (2012-2015), I advocated for instating the double blind manuscript review process that the journal now employs. My experiences in a faculty mentoring matrix program at UTK and graduate student mentoring and diversity programs at U Pittsburgh and UTK, in working groups, and my life experiences, reinforce my belief in the power of human networks to increase individual and group success and happiness. I would work to develop of new mentoring opportunities for ASN scientists at all career levels that foster their professional and personal goals and help to build a stronger, more inclusive community within ASN. Mark Kirkpatrick, University of Texas at Austin My work uses genetics to study classic topics in evolution (e.g. speciation, local adaptation, chromosome evolution), ecology (e.g. species ranges), and behavior (e.g. mate choice, sexual antagonism). My background is in population genetics theory, but recently the lab has moved strongly into genomics.&nbsp; I was an undergraduate at Harvard and received a PhD from the University of Washington.&nbsp; I have several of the accoutrements of aging academics:&nbsp; fellowships in the AAAS (both of them), a Guggenheim, and (best yet) the Sewall Wright Award from the ASN.&nbsp; Service to our community includes the editorial boards of a half dozen journals and conservation work in Central Texas.&nbsp; I have served on the ASN’s Editorial Board, Editor Search Committee, Officer Nomination Committee, Sewall Wright Award Committee, and also contributed innumerable reviews As ASN President, my first priority will be to “Make the American Naturalist Great Again”.&nbsp; (Embroidered caps will be available in all colors but red.)&nbsp; In recent years, the Society has made major progress in key directions:&nbsp; membership is growing, for example, and the stand-alone meetings are a great success.&nbsp; But the Naturalist is at risk of losing its hallowed status as a pillar of the field.&nbsp; I will work closely with the Editor to expand the journal’s visibility and impact.&nbsp; We need to make the journal more relevant to growth points such as genomics and climate change biology.&nbsp; Second, I will work to make the Society more diverse.&nbsp; The current Executive Council is gender balanced (indeed, female biased), but it and the ASN as a whole is still very largely the domain of white scientists.&nbsp; Last, I will put an equation in every pot. The VICE-PRESIDENT organizes the Vice-President’s Symposium for the annual meeting and edits the special supplement to The American Naturalist that contains the papers derived from the VP Symposium. The Vice-President is also the Society’s liaison for the organizers of the annual meeting. The Vice-President serves as a member of the Executive Council for three years, two as a regular member and one as ex officio member.&nbsp; Meghan Duffy, University of Michigan My research focuses on the ecology and evolution of infectious diseases, particularly in aquatic systems. I have studied the causes and consequences of rapid evolution of hosts in response to disease outbreaks, as well as the effects of food webs on disease. More recently, my work has begun to focus on the impacts of global change on infectious diseases, as well as on multihost-multipathogen interactions. I received my PhD from Michigan State University and did a postdoc at the University of Wisconsin before beginning my first faculty position at Georgia Tech; I am now an Associate Professor of Ecology and Evolutionary Biology at the University of Michigan. I received the President’s Early Career Award for Scientists and Engineers from President Obama and the Ecological Society of America’s Mercer Award (for a paper published in AmNat!), and am currently a Public Engagement Fellow with AAAS. I have been an Associate Editor for the American Naturalist since 2015 and served on the American Naturalist Editor-in-Chief Selection committee in 2016. I was the Vice-Chair and then Chair of the Ecological Society of America’s (ESA) Aquatic Ecology Section, was a member of ESA’s Grants and Fellowships committee, and am currently the chair of ESA’s Mercer Award subcommittee. I am a co-creator of DiversifyEEB (which aims to highlight ecologists and evolutionary biologists who are women and/or underrepresented minorities) and of EEBMentorMatch (which aims to provide grad school and fellowship applicants with feedback on their application materials). I also serve on the Advisory Board of 500 Women Scientists, which aims to transform leadership, diversity, and public engagement in science. The ASN website notes that the “American Society of Naturalists emphasizes the value of interdisciplinary research and collaborations between diverse biologists to achieve conceptual unification across the biological sciences.” This is exactly why I want to serve the ASN – there is much to be gained by integrating across ecology, evolutionary biology, and behavior, and it is imperative that we work to make science more diverse and inclusive. My planned symposium would focus on insights gained from system-based research, including work on well-established systems as well as on more recently established systems, integrating across ecology, evolution, and behavior. Scott L Nuismer, University of Idaho I am an evolutionary ecologist with a passion for developing mathematical models that inform our understanding of the natural world.&nbsp; My research focuses on species interactions and coevolution, and touches on a range of topics including the impact of ploidy on species interactions, the role coevolution plays in local adaptation and diversification, and coevolution’s contribution to community structure and function. Most recently, my lab is developing statistical methodologies for measuring the strength and intensity of coevolution in the wild and using mathematical models to solve evolutionary challenges arising from rapid advances in genetic engineering. In addition to my research on species interactions and coevolution, I have a keen interest in making mathematical modeling accessible and understandable to biologists. Although great strides have been made since I started graduate school twenty years ago, in many areas of evolution and ecology we still fail to prepare students to understand or develop even the simplest mathematical models. My efforts to address this include integrating basic model building and analysis in my introductory ecology course, individually mentoring biology students, and most recently, publishing a new book: Introduction to coevolutionary theory. By beginning each chapter with a description of the natural history of a well-studied species interaction, and then developing and analyzing a relevant mathematical model one step at a time, I hope this book will make mathematical modeling less intimidating and more approachable for the next generation of coevolutionary biologists. My formal connection with ASN began in 2013 when I became an associate editor for The American Naturalist. Long before this, however, the society and journal had a lasting impact on the trajectory of my career. One pivotal example was reading Mark Kirkpatrick and Nick Barton’s 1997 paper on the evolution of species’ ranges early in graduate school. This paper cemented my interest in mathematical modeling and led me to pursue a postdoctoral position in Mark’s lab. The American Naturalist remains one of the few journals I manage to read regularly and one where I always send my best research. My goal, if elected, is to highlight the insights that can be gained by integrating mathematical modeling with a deep understanding of natural history. To this end, I envision developing a VP symposium featuring collaborations between theoreticians and empiricists that test existing and emerging theories for the role species interactions and coevolution play in biological diversification. The SECRETARY records and publishes the minutes of the annual meeting of the Executive Committee and ensures that elections for Society offices are conducted in a timely manner. In addition, the Secretary works closely with the President with respect to the normal running of the Society, documents the Executive Committee’s actions, sees that the ASN Officer’s handbook and website are up to date, and coordinates communication between the Executive Committee, other societies’ Executive Committees, the University of Chicago Press and ASN membership. The Secretary serves for a three-year term, and then three years as Past Secretary. For both terms, the Secretary is a member of the ASN Executive Committee. Erol Ak&ccedil;ay, University of Pennsylvania My research focuses on the theory of social evolution, broadly construed to include the evolution of animal and human behavior as well as species interactions. I am particularly interested in the evolutionary and proximate mechanisms of cooperation, social structure, and mutualistic interactions. I have undergraduate degrees in Physics and Biology from Middle East Technical University in Turkey and a PhD in Biology from Stanford University. I then did postdoctoral research at NIMBioS (University of Tennessee) and Princeton University before starting as Assistant Professor at the University of Pennsylvania in 2014. I received the Samuel Karlin Prize in Mathematical Biology (2008) from Stanford University Department of Biology and the Young Investigator award from the Turkish-American Scientists and Scholars Association (2016). One of the things I am proudest of in my past service is helping to start an informal group of researchers from Turkey that eventually became the Ecology and Evolutionary Biology Society of Turkey (https://ekoevo.org/society-for-ecology-and-evolutionary-biology-turkey/). I also co-organized a workshop and served in the scientific committee for the Society&#39;s annual symposia. I have also been active in the past with the ASN, serving for three years on the student research award committee (2014-2017) and more recently, as an Associate Editor for the American Naturalist. For some time now, ASN and the American Naturalist have been my intellectual home in science, representing a truly integrative approach to biology and affiliated sciences. I am proud to be part of this community and to have contributed a little to the mission of the ASN. I would very much welcome the chance to continue doing so as Secretary. Tadashi Fukami, Stanford University I study ecological and evolutionary community assembly, with a focus on understanding when and why the structure and function of communities are contingent on the history of species immigration. Over the past 15 years, I have used experimental, theoretical, and observational methods, involving bacteria, protists, fungi, plants, and animals. Currently, microbes that inhabit floral nectar are my primary study system. I earned a bachelor&#39;s degree from Waseda University in 1996, a master&#39;s degree from the University of Tokyo in 1998, and a PhD from the University of Tennessee, Knoxville, in 2003. I was a postdoc at Landcare Research, New Zealand (2003-2005) and an Assistant Professor at the University of Hawaii at Manoa (2006-2008) before joining the Stanford University faculty in 2008. I received NSF CAREER, OPUS, and Dimensions of Biodiversity awards, and a Science Prize for Inquiry-Based Instruction from AAAS. I have served as a handling editor (Ecology Letters, Oikos, and PLoS ONE), a symposium organizer (ESA), a review panel member (NSF), and a graduate student representative (University of Tennessee EEB Dept; though a long time ago!). I attended two of the past stand-alone ASN conferences and have published three papers in the American Naturalist (Wittmann and Fukami, forthcoming; Fukami et al. 2017; Olito and Fukami 2009), served as the external reviewer for manuscripts submitted to the journal, and had my graduate student (Devin Leopold) receive an ASN Student Research Award. Serving as ASN Secretary would be a great opportunity to contribute to the society that has published many of the papers that inspired and influenced my research deeply. The stimulating, friendly, and informal atmosphere at the ASN stand-alone conferences that I attended has reinforced my feeling that this is the society that I would like to consider my intellectual home, and I would be excited to help the society continue to thrive. <p>The ASN 2018 Elections are underway for tha offices of President, Vice President, and Secretary. The election website randomizes the order for each person voting, but the names below are in alphabetical order.</p><p>The PRESIDENT leads the ASN Executive Council and selects the membership of the award and officer nomination committees. The President selects the President&rsquo;s Award for the &ldquo;best&rdquo; paper in The American Naturalist in the past year, gives the ASN Presidential Address and presents the Society&rsquo;s awards at the annual meeting, and represents the ASN in multiple other ways through the year. The President serves on the Executive Council for five years, including one year as President-Elect and three years as a Past-President.</p> <p><strong>Susan Kalisz, University of Tennessee, Knoxville </strong></p> <p>My interests are in evolutionary biology and ecology.&nbsp; My research focuses on the evolution of&nbsp; mating system and the role of mating system shifts in speciation in plants, mutualism and mutualism disruption by invasive species, and demographic and population modeling. These research projects intersect in my interest in deeper questions about the effects of human&rsquo;s actions across the globe in altering the tempo and mode of evolution, and the sustainability and conservation of biodiversity. I received my Bachelor&rsquo;s of Science degree from the University of Michigan, where I was inspired by the dazzling diversity, forms and functions of plants. I received my Masters and PhD degrees from the University of Chicago, where I learned how the interaction of ecology and evolutionary forces shaped those dazzling forms. Directly from Chicago, I took a faculty position at Michigan State University where I became a tenured associate professor, then moved to the University of Pittsburgh where I became a full professor in 2001. I joined the University of Tennessee, Knoxville (UTK) in 2015 as Professor and Head of the Department of Ecology and Evolutionary Biology. I was invited to serve as program director in the Division of Environmental Biology at the National Science Foundation (2009-2010) and I currently serve on the Faculty of 1000.</p> <p>I co-led two National Evolution Synthesis Center (NESCent) Working Groups, and served as a member of the NSF microMORPH: Microevolutionary Molecular and Organismic Research in Plant History Research Coordination Network Steering Committee 2010-2017, the Botanical Society of America Merit Awards Committee 2011-2014, and as associate editor for the journals <em>Evolution,</em> <em>Journal of Ecology </em>and <em>The American Naturalist. </em>As a graduate student, I joined ASN (loved to discuss graphs with unlabeled axes), and while serving as one of three Editors for<em> The American Naturalist </em>(2012-2015), I advocated for instating the double blind manuscript review process that the journal now employs. My experiences in a faculty mentoring matrix program at UTK and graduate student mentoring and diversity programs at U Pittsburgh and UTK, in working groups, and my life experiences, reinforce my belief in the power of human networks to increase individual and group success and happiness. I would work to develop of new mentoring opportunities for ASN scientists at all career levels that foster their professional and personal goals and help to build a stronger, more inclusive community within ASN.</p> <p><strong>Mark Kirkpatrick, University of Texas at Austin</strong></p> <p>My work uses genetics to study classic topics in evolution (e.g. speciation, local adaptation, chromosome evolution), ecology (e.g. species ranges), and behavior (e.g. mate choice, sexual antagonism). My background is in population genetics theory, but recently the lab has moved strongly into genomics.&nbsp; I was an undergraduate at Harvard and received a PhD from the University of Washington.&nbsp; I have several of the accoutrements of aging academics:&nbsp; fellowships in the AAAS (both of them), a Guggenheim, and (best yet) the Sewall Wright Award from the ASN.&nbsp; Service to our community includes the editorial boards of a half dozen journals and conservation work in Central Texas.&nbsp; I have served on the ASN&rsquo;s Editorial Board, Editor Search Committee, Officer Nomination Committee, Sewall Wright Award Committee, and also contributed innumerable reviews</p> <p>As ASN President, my first priority will be to &ldquo;Make the <em>American Naturalist </em>Great Again&rdquo;.&nbsp; (Embroidered caps will be available in all colors but red.)&nbsp; In recent years, the Society has made major progress in key directions:&nbsp; membership is growing, for example, and the stand-alone meetings are a great success.&nbsp; But the <em>Naturalist </em>is at risk of losing its hallowed status as a pillar of the field.&nbsp; I will work closely with the Editor to expand the journal&rsquo;s visibility and impact.&nbsp; We need to make the journal more relevant to growth points such as genomics and climate change biology.&nbsp; Second, I will work to make the Society more diverse.&nbsp; The current Executive Council is gender balanced (indeed, female biased), but it and the ASN as a whole is still very largely the domain of white scientists.&nbsp; Last, I will put an equation in every pot.</p> <hr /><p>The VICE-PRESIDENT organizes the Vice-President&rsquo;s Symposium for the annual meeting and edits the special supplement to <em>The American Naturalist</em> that contains the papers derived from the VP Symposium. The Vice-President is also the Society&rsquo;s liaison for the organizers of the annual meeting. The Vice-President serves as a member of the Executive Council for three years, two as a regular member and one as ex officio member.&nbsp;</p> <p><strong>Meghan Duffy, University of Michigan</strong></p> <p>My research focuses on the ecology and evolution of infectious diseases, particularly in aquatic systems. I have studied the causes and consequences of rapid evolution of hosts in response to disease outbreaks, as well as the effects of food webs on disease. More recently, my work has begun to focus on the impacts of global change on infectious diseases, as well as on multihost-multipathogen interactions. I received my PhD from Michigan State University and did a postdoc at the University of Wisconsin before beginning my first faculty position at Georgia Tech; I am now an Associate Professor of Ecology and Evolutionary Biology at the University of Michigan. I received the President&rsquo;s Early Career Award for Scientists and Engineers from President Obama and the Ecological Society of America&rsquo;s Mercer Award (for a paper published in <em>AmNat</em>!), and am currently a Public Engagement Fellow with AAAS.</p> <p>I have been an Associate Editor for the <em>American Naturalist </em>since 2015 and served on the <em>American Naturalist </em>Editor-in-Chief Selection committee in 2016. I was the Vice-Chair and then Chair of the Ecological Society of America&rsquo;s (ESA) Aquatic Ecology Section, was a member of ESA&rsquo;s Grants and Fellowships committee, and am currently the chair of ESA&rsquo;s Mercer Award subcommittee. I am a co-creator of DiversifyEEB (which aims to highlight ecologists and evolutionary biologists who are women and/or underrepresented minorities) and of EEBMentorMatch (which aims to provide grad school and fellowship applicants with feedback on their application materials). I also serve on the Advisory Board of 500 Women Scientists, which aims to transform leadership, diversity, and public engagement in science.</p> <p>The ASN website notes that the &ldquo;American Society of Naturalists emphasizes the value of interdisciplinary research and collaborations between diverse biologists to achieve conceptual unification across the biological sciences.&rdquo; This is exactly why I want to serve the ASN &ndash; there is much to be gained by integrating across ecology, evolutionary biology, and behavior, and it is imperative that we work to make science more diverse and inclusive. My planned symposium would focus on insights gained from system-based research, including work on well-established systems as well as on more recently established systems, integrating across ecology, evolution, and behavior.</p> <p><strong>Scott L Nuismer, University of Idaho</strong></p> <p>I am an evolutionary ecologist with a passion for developing mathematical models that inform our understanding of the natural world.&nbsp; My research focuses on species interactions and coevolution, and touches on a range of topics including the impact of ploidy on species interactions, the role coevolution plays in local adaptation and diversification, and coevolution&rsquo;s contribution to community structure and function. Most recently, my lab is developing statistical methodologies for measuring the strength and intensity of coevolution in the wild and using mathematical models to solve evolutionary challenges arising from rapid advances in genetic engineering.</p> <p>In addition to my research on species interactions and coevolution, I have a keen interest in making mathematical modeling accessible and understandable to biologists. Although great strides have been made since I started graduate school twenty years ago, in many areas of evolution and ecology we still fail to prepare students to understand or develop even the simplest mathematical models. My efforts to address this include integrating basic model building and analysis in my introductory ecology course, individually mentoring biology students, and most recently, publishing a new book: Introduction to coevolutionary theory. By beginning each chapter with a description of the natural history of a well-studied species interaction, and then developing and analyzing a relevant mathematical model one step at a time, I hope this book will make mathematical modeling less intimidating and more approachable for the next generation of coevolutionary biologists.</p> <p>My formal connection with ASN began in 2013 when I became an associate editor for <em>The American Naturalist. </em>Long before this, however, the society and journal had a lasting impact on the trajectory of my career. One pivotal example was reading Mark Kirkpatrick and Nick Barton&rsquo;s 1997 paper on the evolution of species&rsquo; ranges early in graduate school. This paper cemented my interest in mathematical modeling and led me to pursue a postdoctoral position in Mark&rsquo;s lab. <em>The American Naturalist </em>remains one of the few journals I manage to read regularly and one where I always send my best research. My goal, if elected, is to highlight the insights that can be gained by integrating mathematical modeling with a deep understanding of natural history. To this end, I envision developing a VP symposium featuring collaborations between theoreticians and empiricists that test existing and emerging theories for the role species interactions and coevolution play in biological diversification.</p> <hr /><p>The SECRETARY records and publishes the minutes of the annual meeting of the Executive Committee and ensures that elections for Society offices are conducted in a timely manner. In addition, the Secretary works closely with the President with respect to the normal running of the Society, documents the Executive Committee&rsquo;s actions, sees that the ASN Officer&rsquo;s handbook and website are up to date, and coordinates communication between the Executive Committee, other societies&rsquo; Executive Committees, the University of Chicago Press and ASN membership. The Secretary serves for a three-year term, and then three years as Past Secretary. For both terms, the Secretary is a member of the ASN Executive Committee.</p> <p><strong>Erol Ak&ccedil;ay, University of Pennsylvania</strong></p> <p>My research focuses on the theory of social evolution, broadly construed to include the evolution of animal and human behavior as well as species interactions. I am particularly interested in the evolutionary and proximate mechanisms of cooperation, social structure, and mutualistic interactions. I have undergraduate degrees in Physics and Biology from Middle East Technical University in Turkey and a PhD in Biology from Stanford University. I then did postdoctoral research at NIMBioS (University of Tennessee) and Princeton University before starting as Assistant Professor at the University of Pennsylvania in 2014. I received the Samuel Karlin Prize in Mathematical Biology (2008) from Stanford University Department of Biology and the Young Investigator award from the Turkish-American Scientists and Scholars Association (2016).</p> <p>One of the things I am proudest of in my past service is helping to start an informal group of researchers from Turkey that eventually became the Ecology and Evolutionary Biology Society of Turkey (<a href="https://ekoevo.org/society-for-ecology-and-evolutionary-biology-turkey/">https://ekoevo.org/society-for-ecology-and-evolutionary-biology-turkey/</a>). I also co-organized a workshop and served in the scientific committee for the Society&#39;s annual symposia. I have also been active in the past with the ASN, serving for three years on the student research award committee (2014-2017) and more recently, as an Associate Editor for the <em>American Naturalist. </em>For some time now, ASN and the <em>American Naturalist </em>have been my intellectual home in science, representing a truly integrative approach to biology and affiliated sciences. I am proud to be part of this community and to have contributed a little to the mission of the ASN. I would very much welcome the chance to continue doing so as Secretary.</p> <p><strong>Tadashi Fukami, Stanford University</strong></p> <p>I study ecological and evolutionary community assembly, with a focus on understanding when and why the structure and function of communities are contingent on the history of species immigration. Over the past 15 years, I have used experimental, theoretical, and observational methods, involving bacteria, protists, fungi, plants, and animals. Currently, microbes that inhabit floral nectar are my primary study system. I earned a bachelor&#39;s degree from Waseda University in 1996, a master&#39;s degree from the University of Tokyo in 1998, and a PhD from the University of Tennessee, Knoxville, in 2003. I was a postdoc at Landcare Research, New Zealand (2003-2005) and an Assistant Professor at the University of Hawaii at Manoa (2006-2008) before joining the Stanford University faculty in 2008. I received NSF CAREER, OPUS, and Dimensions of Biodiversity awards, and a Science Prize for Inquiry-Based Instruction from AAAS.</p> <p>I have served as a handling editor (<em>Ecology Letters</em>, <em>Oikos</em>, and <em>PLoS ONE</em>), a symposium organizer (ESA), a review panel member (NSF), and a graduate student representative (University of Tennessee EEB Dept; though a long time ago!). I attended two of the past stand-alone ASN conferences and have published three papers in the <em>American Naturalist </em>(Wittmann and Fukami, forthcoming; Fukami et al. 2017; Olito and Fukami 2009), served as the external reviewer for manuscripts submitted to the journal, and had my graduate student (Devin Leopold) receive an ASN Student Research Award. Serving as ASN Secretary would be a great opportunity to contribute to the society that has published many of the papers that inspired and influenced my research deeply. The stimulating, friendly, and informal atmosphere at the ASN stand-alone conferences that I attended has reinforced my feeling that this is the society that I would like to consider my intellectual home, and I would be excited to help the society continue to thrive.</p> <hr /> Thu, 08 Feb 2018 06:00:00 GMT “A genomic imprinting model of termite caste determination: Not genetic but epigenetic inheritance influences offspring caste fate” http://amnat.org/an/newpapers/JuneMatsuura.html The DOI will be https://dx.doi.org/10.1086/697238 Parental phenotypes influence caste differentiation of offspring through genomic imprinting in termites Is royalty an inherited trait in social insects? In termites, parental phenotypes influence the caste fate of the offspring. For example, female offspring of sexually matured queens and worker-derived males develop exclusively into queens, as do parthenogenetically produced daughters. Such heritable effects on caste propensity has been recognized as an evidence of genetic caste determination. Matsuura and colleagues (2018) demonstrate that parental phenotypes influence the social status of the offspring not through genetic inheritance but through genomic imprinting. They conducted extensive field survey and genetic analysis of the termite Reticulitermes speratus and concluded that the caste system of this species cannot be explained by genetic caste determination models. Alternatively, they documented a genomic imprinting caste determination system in termites, in which queen- and king-specific epigenetic marks antagonistically influence the sexual development of offspring and thus determine their caste fate. Their work emphasizes that the genomic imprinting model accounts for all known empirical data on caste differentiation in termites and explains the evolutionary processes underlying diverse reproductive systems. According to the genomic imprinting model, the worker caste is seen as a ‘neuter’ caste whose sexual development is suppressed due to counterbalanced maternal and paternal imprinting. This model opens new avenues for understanding the evolution of caste systems in social insects. Abstract Eusocial insects exhibit the most striking example of phenotypic plasticity. There has been a long controversy over the factors determining caste development of individuals in social insects. Here we demonstrate that parental phenotypes influence the social status of offspring not through genetic inheritance but through genomic imprinting in termites. Our extensive field survey and genetic analysis of the termite Reticulitermes speratus show that its breeding system is inconsistent with a genetic caste determination model. We therefore developed a genomic imprinting model, in which queen- and king-specific epigenetic marks antagonistically influence sexual development of offspring. The model accounts for all known empirical data on caste differentiation of R.&nbsp;speratus and other related species. By conducting colony-founding experiments and additively incorporating relevant socio-environmental factors into our genomic imprinting model, we show the relative importance of genomic imprinting and environmental factors in caste determination. The idea of epigenetic inheritance of sexual phenotypes solves the puzzle of why parthenogenetically-produced daughters carrying only maternal chromosomes exclusively develop into queens and why parental phenotypes (nymph- or worker-derived reproductives) strongly influence caste differentiation of offspring. According to our model, the worker caste is seen as a ‘neuter’ caste whose sexual development is suppressed due to counterbalanced maternal and paternal imprinting and opens new avenues for understanding the evolution of caste systems in social insects. More forthcoming papers &raquo; <p><i>The DOI will be https://dx.doi.org/10.1086/697238 </i></p> <p><b>Parental phenotypes influence caste differentiation of offspring through genomic imprinting in termites </b></p><p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">I</span>s royalty an inherited trait in social insects? In termites, parental phenotypes influence the caste fate of the offspring. For example, female offspring of sexually matured queens and worker-derived males develop exclusively into queens, as do parthenogenetically produced daughters. Such heritable effects on caste propensity has been recognized as an evidence of genetic caste determination. Matsuura and colleagues (2018) demonstrate that parental phenotypes influence the social status of the offspring not through genetic inheritance but through genomic imprinting. They conducted extensive field survey and genetic analysis of the termite <i>Reticulitermes speratus</i> and concluded that the caste system of this species cannot be explained by genetic caste determination models. Alternatively, they documented a genomic imprinting caste determination system in termites, in which queen- and king-specific epigenetic marks antagonistically influence the sexual development of offspring and thus determine their caste fate. Their work emphasizes that the genomic imprinting model accounts for all known empirical data on caste differentiation in termites and explains the evolutionary processes underlying diverse reproductive systems. According to the genomic imprinting model, the worker caste is seen as a ‘neuter’ caste whose sexual development is suppressed due to counterbalanced maternal and paternal imprinting. This model opens new avenues for understanding the evolution of caste systems in social insects. </p> <hr /> <h3>Abstract</h3> <p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">E</span>usocial insects exhibit the most striking example of phenotypic plasticity. There has been a long controversy over the factors determining caste development of individuals in social insects. Here we demonstrate that parental phenotypes influence the social status of offspring not through genetic inheritance but through genomic imprinting in termites. Our extensive field survey and genetic analysis of the termite <i>Reticulitermes speratus</i> show that its breeding system is inconsistent with a genetic caste determination model. We therefore developed a genomic imprinting model, in which queen- and king-specific epigenetic marks antagonistically influence sexual development of offspring. The model accounts for all known empirical data on caste differentiation of <i>R.&nbsp;speratus</i> and other related species. By conducting colony-founding experiments and additively incorporating relevant socio-environmental factors into our genomic imprinting model, we show the relative importance of genomic imprinting and environmental factors in caste determination. The idea of epigenetic inheritance of sexual phenotypes solves the puzzle of why parthenogenetically-produced daughters carrying only maternal chromosomes exclusively develop into queens and why parental phenotypes (nymph- or worker-derived reproductives) strongly influence caste differentiation of offspring. According to our model, the worker caste is seen as a ‘neuter’ caste whose sexual development is suppressed due to counterbalanced maternal and paternal imprinting and opens new avenues for understanding the evolution of caste systems in social insects. </p> <!-- <p><a href="https://dx.doi.org/10.1086/697238">Read&nbsp;the&nbsp;Article</a> </p> --> <div style="float: right;"><a href="http://www.amnat.org/an/newpapers.html"> <span style="font-size: large; font-family: Georgia;"><i>More forthcoming papers</i> &raquo;</span></a></div> Mon, 05 Feb 2018 06:00:00 GMT “Chronological and biological age predict seasonal reproductive timing: an investigation of clutch initiation and telomeres in birds of known age” http://amnat.org/an/newpapers/JuneBauer.html The DOI will be http://dx.doi.org/10.1086/697224 Older birds or those with shorter telomeres (closer to senescence) breed earlier (increase seasonal reproductive effort) For seasonally breeding birds, individuals that breed earlier in the season tend to have higher reproductive success than birds that breed later. Why, then, do we see variation in the timing of when females lay their first clutch of eggs? Evidence from other studies suggests that it’s costly for females to breed early in the season, as early breeding females are less likely to survive to the next year. Lead author Carolyn Bauer (Adelphi University) wondered if the number of future breeding seasons a female is expected to have might influence timing of reproduction. The question is, do birds with fewer, future reproductive events increase their current reproductive effort by breeding earlier in the season? To determine the number of “future reproductive events,” Bauer and colleagues (Jessica Graham, Britt Heidinger, and Timothy Greives from North Dakota State University, and Mikus Abolins-Abols and Ellen Ketterson from Indiana University), measured both chronological age and an estimate of biological age in a population of Dark-eyed Juncos (Junco hyemalis) at Mountain Lake Biological Station in western Virginia. Chronological age was determined from banding records. Biological age was estimated by measuring the length of telomeres, which are located at the ends of chromosomes and shorten during cell division and in response to stress exposure. Timing of breeding was determined via intensive searching for nests at the start of two breeding seasons. Together, Bauer and colleagues found that both older females and those with shorter telomeres tended to breed earlier. Importantly, these effects were independent of each other, as telomere length did not differ between old and young birds. These findings suggest that females may increase their reproductive effort when they have fewer expected future breeding events. The next exciting question is which cues of remaining lifespan are birds potentially using to adjust reproductive timing? Abstract Female vertebrates that breed earlier in the season generally have greater reproductive success. However, evidence suggests that breeding early may be costly, thus leading to the prediction that females with fewer future reproductive events will breed earlier in the season. While chronological age is a good indicator of remaining lifespan, telomere lengths may also be good biomarkers of longevity as they potentially reflect lifetime ‘wear and tear’ (i.e. “biological age”). We examined whether variation in the timing of the first seasonal clutch was related to age and telomere length in female dark-eyed juncos (Junco hyemalis), predicting that older females and those with shorter telomeres would breed earlier. Both predictions held true and were independent of each other, as telomere length did not significantly vary with age. These results suggest that females may adjust their reproductive effort based on both chronological and biological age. More forthcoming papers &raquo; <p><i>The DOI will be http://dx.doi.org/10.1086/697224 </i></p> <p><b>Older birds or those with shorter telomeres (closer to senescence) breed earlier (increase seasonal reproductive effort) </b></p><p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">F</span>or seasonally breeding birds, individuals that breed earlier in the season tend to have higher reproductive success than birds that breed later. Why, then, do we see variation in the timing of when females lay their first clutch of eggs? Evidence from other studies suggests that it’s costly for females to breed early in the season, as early breeding females are less likely to survive to the next year. Lead author Carolyn Bauer (Adelphi University) wondered if the number of future breeding seasons a female is expected to have might influence timing of reproduction. The question is, do birds with fewer, future reproductive events increase their current reproductive effort by breeding earlier in the season? </p><p>To determine the number of “future reproductive events,” Bauer and colleagues (Jessica Graham, Britt Heidinger, and Timothy Greives from North Dakota State University, and Mikus Abolins-Abols and Ellen Ketterson from Indiana University), measured both chronological age and an estimate of biological age in a population of Dark-eyed Juncos (<i>Junco hyemalis</i>) at Mountain Lake Biological Station in western Virginia. Chronological age was determined from banding records. Biological age was estimated by measuring the length of telomeres, which are located at the ends of chromosomes and shorten during cell division and in response to stress exposure. Timing of breeding was determined via intensive searching for nests at the start of two breeding seasons. </p><p>Together, Bauer and colleagues found that both older females and those with shorter telomeres tended to breed earlier. Importantly, these effects were independent of each other, as telomere length did not differ between old and young birds. These findings suggest that females may increase their reproductive effort when they have fewer expected future breeding events. The next exciting question is which cues of remaining lifespan are birds potentially using to adjust reproductive timing? </p> <hr /><h3>Abstract</h3> <p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">F</span>emale vertebrates that breed earlier in the season generally have greater reproductive success. However, evidence suggests that breeding early may be costly, thus leading to the prediction that females with fewer future reproductive events will breed earlier in the season. While chronological age is a good indicator of remaining lifespan, telomere lengths may also be good biomarkers of longevity as they potentially reflect lifetime ‘wear and tear’ (i.e. “biological age”). We examined whether variation in the timing of the first seasonal clutch was related to age and telomere length in female dark-eyed juncos (<i>Junco hyemalis</i>), predicting that older females and those with shorter telomeres would breed earlier. Both predictions held true and were independent of each other, as telomere length did not significantly vary with age. These results suggest that females may adjust their reproductive effort based on both chronological and biological age. </p> <!-- <p><a href="http://dx.doi.org/10.1086/697224">Read&nbsp;the&nbsp;Article</a> </p> --> <div style="float: right;"><a href="http://www.amnat.org/an/newpapers.html"> <span style="font-size: large; font-family: Georgia;"><i>More forthcoming papers</i> &raquo;</span></a></div> Mon, 05 Feb 2018 06:00:00 GMT “Dispensing pollen via catapult: Explosive pollen release in mountain laurel (Kalmia latifolia)” http://amnat.org/an/newpapers/JuneSwitzer.html The DOI will be https://dx.doi.org/10.1086/697220 Mountain laurels launch pollen at 400 times the acceleration due to gravity Flowers are not known for their fast movements, but the mountain laurel flower propels pollen into the air at incredible speeds. These flowers are equipped with ten tiny pollen catapults. But where does this pollen go and why is it launched? Callin Switzer, Stacey Combes, and Robin Hopkins, strived to answer these questions through an in-depth study of how this unique flower functions – they investigated the importance of the explosive pollination mechanism in reproduction and characterized the biomechanics of this quick-moving flower. Using high-speed videos, the authors were able to track where the pollen goes after being launched from the flower. With these data, they created a three-dimensional map of where a pollinator needs to be in order to be hit by pollen. They found that the catapults are likely to launch pollen towards the center of the flower, which would hit insects like bumblebees as they collect nectar. Through careful tracking of pollen movement, this study documents one of the fastest plants ever described – mountain laurel flowers accelerate pollen at over 400&nbsp;g, and the pollen reaches a top speed of around 3.5&nbsp;m/s (about 8&nbsp;mph). Complementing the mechanical description of the mountain laurel flower is a pollination study that determines that insects are important for activating the catapult and pollinating flowers. When pollinators were excluded from visiting the flowers, mountain laurels produced little or no seeds. This work represents a high-speed glimpse into the function of flower form. Abstract The astonishing amount of floral diversity has inspired countless assumptions about the function of diverse forms and their adaptive significance; yet many of these hypothesized functions are untested. We investigated an often-repeated adaptive hypothesis about how an extreme floral form functions. In this study, we conducted four investigations to understand the adaptive function of explosive pollination in Kalmia latifolia, the mountain laurel. We first performed a kinematic analysis of anther movement. Second, we constructed a heat map of pollen trajectories in three-dimensional space. Third, we conducted field observations of pollinators and their behaviors while visiting K.&nbsp;latifolia. Finally, we conducted a pollination experiment to investigate the importance of pollinators for fertilization success. Our results suggest that insect visitation dramatically improves fertilization success and that bees are the primary pollinators that trigger explosive pollen release. More forthcoming papers &raquo; <p><i>The DOI will be https://dx.doi.org/10.1086/697220 </i></p> <p><b>Mountain laurels launch pollen at 400 times the acceleration due to gravity </b></p><p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">F</span>lowers are not known for their fast movements, but the mountain laurel flower propels pollen into the air at incredible speeds. These flowers are equipped with ten tiny pollen catapults. But where does this pollen go and why is it launched? </p> <p>Callin Switzer, Stacey Combes, and Robin Hopkins, strived to answer these questions through an in-depth study of how this unique flower functions – they investigated the importance of the explosive pollination mechanism in reproduction and characterized the biomechanics of this quick-moving flower. </p><p>Using high-speed videos, the authors were able to track where the pollen goes after being launched from the flower. With these data, they created a three-dimensional map of where a pollinator needs to be in order to be hit by pollen. They found that the catapults are likely to launch pollen towards the center of the flower, which would hit insects like bumblebees as they collect nectar. Through careful tracking of pollen movement, this study documents one of the fastest plants ever described – mountain laurel flowers accelerate pollen at over 400&nbsp;g, and the pollen reaches a top speed of around 3.5&nbsp;m/s (about 8&nbsp;mph). </p> <p>Complementing the mechanical description of the mountain laurel flower is a pollination study that determines that insects are important for activating the catapult and pollinating flowers. When pollinators were excluded from visiting the flowers, mountain laurels produced little or no seeds. </p> <p>This work represents a high-speed glimpse into the function of flower form. </p><h3>Abstract</h3> <p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">T</span>he astonishing amount of floral diversity has inspired countless assumptions about the function of diverse forms and their adaptive significance; yet many of these hypothesized functions are untested. We investigated an often-repeated adaptive hypothesis about how an extreme floral form functions. In this study, we conducted four investigations to understand the adaptive function of explosive pollination in <i>Kalmia latifolia</i>, the mountain laurel. We first performed a kinematic analysis of anther movement. Second, we constructed a heat map of pollen trajectories in three-dimensional space. Third, we conducted field observations of pollinators and their behaviors while visiting <i>K.&nbsp;latifolia</i>. Finally, we conducted a pollination experiment to investigate the importance of pollinators for fertilization success. Our results suggest that insect visitation dramatically improves fertilization success and that bees are the primary pollinators that trigger explosive pollen release. </p> <!-- <p><a href="https://dx.doi.org/10.1086/697220">Read&nbsp;the&nbsp;Article</a> </p> --> <div style="float: right;"><a href="http://www.amnat.org/an/newpapers.html"> <span style="font-size: large; font-family: Georgia;"><i>More forthcoming papers</i> &raquo;</span></a></div> Mon, 05 Feb 2018 06:00:00 GMT “Sex-dependent expression and fitness consequences of sunlight-derived color phenotypes” http://amnat.org/an/newpapers/JuneFargallo.html The DOI will be http://dx.doi.org/10.1086/697218 Color variation in birds related to sunlight-temperature conditions as a potential capacity for acclimatization There is no clear evidence of whether endothermic animals respond to environmental variations in solar radiation or temperature through changes in external coloration. A new study by researchers from the National Museum of Natural Sciences–CSIC in Madrid, Spain, in collaboration with researchers from the Doñana Biological Station–CSIC, Spain, and Fujita Health University, Japan, shows that griffon vultures Gyps fulvus that have grown up in nests more exposed to sunlight produce paler plumages. The researchers also find that females show paler plumages than males and that lighter males show higher mortality during the first years of life. The interest of the study lies in three main points: (i) the possibility that endothermic animals, such as birds, might respond to variations in sunlight-temperature by changing coloration, (ii) the potential costs of trait plasticity, with males being more sensitive to them, and (iii) the differences in survival associated with coloration, which may be an ecological mechanism promoting sexual dimorphism. The study was conducted in the Hoces del Riaza Natural Park, Segovia, Spain, from 1996 to 2015. To understand whether early phenotypes are adaptive, knowledge of the environmental factors involved in their variation and the derived benefits from their expression is needed. Temperature and sunlight are considered two major selective forces influencing phenotypic coloration of birds at a global scale. However, within-population color adaptations in response to sunlight-temperature variation have been scarcely investigated and their acclimatization capacity is currently unknown. In addition, the sexes differ in their sensitivity to environmental factors during growth. This study evaluates how melanin plumage coloration varies in relation to sex and sunlight exposure in developing griffon vultures Gyps fulvus, and how this correlates with survival. The results show that individuals grown in nests more exposed to sunlight developed paler plumages as predicted by the thermal melanism hypothesis. In addition, paler males, but not females, have lower survival probability. Finally, a significant sexual dichromatism in fledgling plumage was observed, with females being paler than males. These results reveal within-population color variation related to sunlight-temperature conditions, probably as a capacity for local acclimatization through color plasticity, and also provide evidence of sex differences in fitness optima for this trait under ecological pressures. More forthcoming papers &raquo; <p><i>The DOI will be http://dx.doi.org/10.1086/697218 </i></p> <p><b>Color variation in birds related to sunlight-temperature conditions as a potential capacity for acclimatization </b></p><p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">T</span>here is no clear evidence of whether endothermic animals respond to environmental variations in solar radiation or temperature through changes in external coloration. A new study by researchers from the National Museum of Natural Sciences–CSIC in Madrid, Spain, in collaboration with researchers from the Doñana Biological Station–CSIC, Spain, and Fujita Health University, Japan, shows that griffon vultures <i>Gyps fulvus</i> that have grown up in nests more exposed to sunlight produce paler plumages. The researchers also find that females show paler plumages than males and that lighter males show higher mortality during the first years of life. The interest of the study lies in three main points: (i) the possibility that endothermic animals, such as birds, might respond to variations in sunlight-temperature by changing coloration, (ii) the potential costs of trait plasticity, with males being more sensitive to them, and (iii) the differences in survival associated with coloration, which may be an ecological mechanism promoting sexual dimorphism. The study was conducted in the Hoces del Riaza Natural Park, Segovia, Spain, from 1996 to 2015. </p><p><span style="line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-size: 40px; font-weight: bold; float: left;">T</span>o understand whether early phenotypes are adaptive, knowledge of the environmental factors involved in their variation and the derived benefits from their expression is needed. Temperature and sunlight are considered two major selective forces influencing phenotypic coloration of birds at a global scale. However, within-population color adaptations in response to sunlight-temperature variation have been scarcely investigated and their acclimatization capacity is currently unknown. In addition, the sexes differ in their sensitivity to environmental factors during growth. This study evaluates how melanin plumage coloration varies in relation to sex and sunlight exposure in developing griffon vultures <i>Gyps fulvus</i>, and how this correlates with survival. The results show that individuals grown in nests more exposed to sunlight developed paler plumages as predicted by the thermal melanism hypothesis. In addition, paler males, but not females, have lower survival probability. Finally, a significant sexual dichromatism in fledgling plumage was observed, with females being paler than males. These results reveal within-population color variation related to sunlight-temperature conditions, probably as a capacity for local acclimatization through color plasticity, and also provide evidence of sex differences in fitness optima for this trait under ecological pressures.</p> <!-- <p><a href="http://dx.doi.org/10.1086/697218">Read&nbsp;the&nbsp;Article</a> </p> --> <div style="float: right;"><a href="http://www.amnat.org/an/newpapers.html"><span style="font-family: Georgia; font-size: large;"><i>More forthcoming papers</i> &raquo;</span></a></div> Mon, 05 Feb 2018 06:00:00 GMT “How life history shapes optimal patterns of senescence: implications from individuals to societies” http://amnat.org/an/newpapers/JuneLemanski-A.html The DOI will be https://dx.doi.org/10.1086/697225 Abstract One evolutionary view of aging, the disposable soma theory, suggests that an organism’s rate of senescence depends on the amount of energy invested in somatic maintenance. Since organisms have limited energy to allocate among growth, maintenance, and reproduction, the optimal amount of energy to invest in maintenance is influenced by the probability of death from extrinsic causes and the effect of somatic investment on survival. In eusocial animals, the disposable soma theory can be used to explain colonies’ energy investment in the longevity of workers, who act as the somatic elements of a superorganism. There have been few theoretical considerations of how changes in the costliness of worker maintenance or in the effect of individual lifespan on group fitness, influence a colony’s investment in worker longevity. We develop a decision theory model to evaluate how changing the marginal costs and benefits of longevity, and extrinsic mortality, influence optimal worker lifespan in a social insect colony. Our model predicts that higher extrinsic mortality favors shorter lifespan. However, increased lifespan is favored when marginal benefits are an increasing function of longevity. In honeybees, this explains how greater somatic investment is sometimes favored despite high mortality. Our approach expands the disposable soma theory to make quantitative predictions about the selective pressures shaping senescence in social systems. More forthcoming papers &raquo; <p><i>The DOI will be https://dx.doi.org/10.1086/697225 </i></p><h3>Abstract</h3> <p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">O</span>ne evolutionary view of aging, the disposable soma theory, suggests that an organism’s rate of senescence depends on the amount of energy invested in somatic maintenance. Since organisms have limited energy to allocate among growth, maintenance, and reproduction, the optimal amount of energy to invest in maintenance is influenced by the probability of death from extrinsic causes and the effect of somatic investment on survival. In eusocial animals, the disposable soma theory can be used to explain colonies’ energy investment in the longevity of workers, who act as the somatic elements of a superorganism. There have been few theoretical considerations of how changes in the costliness of worker maintenance or in the effect of individual lifespan on group fitness, influence a colony’s investment in worker longevity. We develop a decision theory model to evaluate how changing the marginal costs and benefits of longevity, and extrinsic mortality, influence optimal worker lifespan in a social insect colony. Our model predicts that higher extrinsic mortality favors shorter lifespan. However, increased lifespan is favored when marginal benefits are an increasing function of longevity. In honeybees, this explains how greater somatic investment is sometimes favored despite high mortality. Our approach expands the disposable soma theory to make quantitative predictions about the selective pressures shaping senescence in social systems. </p> <!-- <p><a href="https://dx.doi.org/10.1086/697225">Read&nbsp;the&nbsp;Article</a> </p> --> <div style="float: right;"><a href="http://www.amnat.org/an/newpapers.html"> <span style="font-size: large; font-family: Georgia;"><i>More forthcoming papers</i> &raquo;</span></a></div> Mon, 05 Feb 2018 06:00:00 GMT “Effects of offspring and parental inbreeding on parent-offspring communication” http://amnat.org/an/newpapers/JuneMattey-A.html The DOI will be https://dx.doi.org/10.1086/697236 Outbred parents provide more care inbred offspring to compensate for the detrimental effects of poor genetic quality Abstract There is mounting evidence that inbreeding can have complex effects on social interactions among inbred and outbred individuals. Here, we investigate effects of offspring and maternal inbreeding on parent-offspring communication in the burying beetle Nicrophorus vespilloides. We find effects of the interaction between offspring and maternal inbreeding on maternal behavior. Outbred females provided more direct care towards inbred larvae, while inbred females provided similar levels of direct care towards inbred and outbred larvae. Furthermore, we find direct and indirect effects of offspring inbreeding on offspring begging and maternal behavior, respectively. Inbred larvae spent less time begging than outbred larvae, and (outbred) females provided more direct care and less indirect care towards inbred larvae. Finally, we find effects of the interaction between offspring and maternal inbreeding on larval body mass. Inbred and outbred offspring grew to a similar size when the female was outbred, whilst inbred offspring were smaller size when the female was inbred. Our results suggest that outbred females provided more care towards inbred offspring to compensate for their poor genetic quality. Our study advances our understanding of inbreeding by showing that inbreeding can have direct effects on the behavior of inbred individuals and indirect effects on the behavior of outbred individuals, and that indirect effects on outbred individuals, in turn, may influence the fitness of inbred individuals. More forthcoming papers &raquo; <p><i>The DOI will be https://dx.doi.org/10.1086/697236 </i></p> <p><b>Outbred parents provide more care inbred offspring to compensate for the detrimental effects of poor genetic quality </b></p><h3>Abstract</h3> <p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">T</span>here is mounting evidence that inbreeding can have complex effects on social interactions among inbred and outbred individuals. Here, we investigate effects of offspring and maternal inbreeding on parent-offspring communication in the burying beetle <i>Nicrophorus vespilloides</i>. We find effects of the interaction between offspring and maternal inbreeding on maternal behavior. Outbred females provided more direct care towards inbred larvae, while inbred females provided similar levels of direct care towards inbred and outbred larvae. Furthermore, we find direct and indirect effects of offspring inbreeding on offspring begging and maternal behavior, respectively. Inbred larvae spent less time begging than outbred larvae, and (outbred) females provided more direct care and less indirect care towards inbred larvae. Finally, we find effects of the interaction between offspring and maternal inbreeding on larval body mass. Inbred and outbred offspring grew to a similar size when the female was outbred, whilst inbred offspring were smaller size when the female was inbred. Our results suggest that outbred females provided more care towards inbred offspring to compensate for their poor genetic quality. Our study advances our understanding of inbreeding by showing that inbreeding can have direct effects on the behavior of inbred individuals and indirect effects on the behavior of outbred individuals, and that indirect effects on outbred individuals, in turn, may influence the fitness of inbred individuals. </p> <!-- <p><a href="https://dx.doi.org/10.1086/697236">Read&nbsp;the&nbsp;Article</a> </p> --> <div style="float: right;"><a href="http://www.amnat.org/an/newpapers.html"> <span style="font-size: large; font-family: Georgia;"><i>More forthcoming papers</i> &raquo;</span></a></div> Mon, 05 Feb 2018 06:00:00 GMT “Comparative evolution of an archetypal adaptive radiation: Innovation and opportunity in Anolis lizards” http://amnat.org/an/newpapers/JunePoe-A.html The DOI will be http://dx.doi.org/10.1086/697223 The most comprehensive comparative analysis of anole lizards sheds new light on their status as an adaptive radiation Abstract Adaptive radiation is a widely recognized pattern of evolution wherein substantial phenotypic change accompanies rapid speciation. Adaptive radiation may be triggered by environmental opportunities resulting from dispersal to new areas or via the evolution of traits, called key innovations, that allow invasion of new niches. Species sampling is a known source of bias in many comparative analyses, yet classic adaptive radiations have not been studied comparatively with comprehensively sampled phylogenies. In this study we use unprecedented comprehensive phylogenetic sampling of Anolis lizard species to examine comparative evolution in this well-studied adaptive radiation. We compare adaptive radiation models within Anolis and in the Anolis clade and a potential sister lineage, the Corytophanidae. We find evidence for island (i.e., opportunity) effects and no evidence for trait (i.e., key innovation) effects causing accelerated body size evolution within Anolis. However, island effects are scale dependent: when Anolis and Corytophanidae are analyzed together, no island effect is evident. We find no evidence for an island effect on speciation rate, and tenuous evidence for greater speciation rate due to trait effects. These results suggest the need for precision in treatments of classic adaptive radiations such as Anolis, and further refinement of the concept of adaptive radiation. More forthcoming papers &raquo; <p><i>The DOI will be http://dx.doi.org/10.1086/697223 </i></p> <p><b>The most comprehensive comparative analysis of anole lizards sheds new light on their status as an adaptive radiation </b></p><h3>Abstract</h3> <p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">A</span>daptive radiation is a widely recognized pattern of evolution wherein substantial phenotypic change accompanies rapid speciation. Adaptive radiation may be triggered by environmental opportunities resulting from dispersal to new areas or via the evolution of traits, called key innovations, that allow invasion of new niches. Species sampling is a known source of bias in many comparative analyses, yet classic adaptive radiations have not been studied comparatively with comprehensively sampled phylogenies. In this study we use unprecedented comprehensive phylogenetic sampling of <i>Anolis</i> lizard species to examine comparative evolution in this well-studied adaptive radiation. We compare adaptive radiation models within <i>Anolis</i> and in the <i>Anolis</i> clade and a potential sister lineage, the Corytophanidae. We find evidence for island (i.e., opportunity) effects and no evidence for trait (i.e., key innovation) effects causing accelerated body size evolution within <i>Anolis</i>. However, island effects are scale dependent: when <i>Anolis</i> and Corytophanidae are analyzed together, no island effect is evident. We find no evidence for an island effect on speciation rate, and tenuous evidence for greater speciation rate due to trait effects. These results suggest the need for precision in treatments of classic adaptive radiations such as <i>Anolis</i>, and further refinement of the concept of adaptive radiation. </p> <!-- <p><a href="http://dx.doi.org/10.1086/697223">Read&nbsp;the&nbsp;Article</a> </p> --> <div style="float: right;"><a href="http://www.amnat.org/an/newpapers.html"> <span style="font-size: large; font-family: Georgia;"><i>More forthcoming papers</i> &raquo;</span></a></div> Mon, 05 Feb 2018 06:00:00 GMT 2018 Grad Student Travel Awards http://amnat.org/announcements/ASNGrad-Travel.html Dear SSE and ASN travel award applicants, Thank you all for applying for a Graduate/Postdoc Travel Award from SSE or ASN. We are delighted by the overwhelming interest among graduate students and postdocs in attending this year’s meeting, the second Joint Congress of SSE, ASN, SSB, and ESEB, to be held in Montpellier, France. Just as the first Joint Congress in Ottawa followed the North American meeting style, this Congress follows typical ESEB style, with limited presentations organized into topical symposia. We are incredibly thankful to ESEB for hosting this Congress and for their tremendous organizational efforts and financial support. In order to facilitate travel for graduate students and postdocs to Montpellier, SSE and ASN both increased their investments in the travel awards this year. We received an impressive 430 applications for travel awards. This is similar to the number of applicants we typically receive, and we will process these applications as soon as possible. Please note, given the number of applicants for presentations at the Congress, we will likely be able to notify recipients around the time that meeting registration opens on March 12. Priority will be given to member applicants who are selected by the organizers to give a talk or poster. If we have fewer awardees presenting than we have travel award funds, then the remaining awards will be offered to non-presenting members who still plan to attend the Congress. We will be sure to notify you as soon as we can with decisions on these travel awards. And if you are chosen, please make sure you register early! Best wishes, Chris Caruso ASN Treasurer Andrea Case SSE Executive Vice President <p>Dear SSE and ASN travel award applicants,</p> <p>Thank you all for applying for a Graduate/Postdoc Travel Award from SSE or ASN. We are delighted by the overwhelming interest among graduate students and postdocs in attending this year&rsquo;s meeting, the second Joint Congress of SSE, ASN, SSB, and ESEB, to be held in Montpellier, France.</p> <p>Just as the first Joint Congress in Ottawa followed the North American meeting style, this Congress follows typical ESEB style, with limited presentations organized into topical symposia. We are incredibly thankful to ESEB for hosting this Congress and for their tremendous organizational efforts and financial support.</p> <p>In order to facilitate travel for graduate students and postdocs to Montpellier, SSE and ASN both increased their investments in the travel awards this year. We received an impressive 430 applications for travel awards. This is similar to the number of applicants we typically receive, and we will process these applications as soon as possible.</p> <p>Please note, given the number of applicants for presentations at the Congress, we will likely be able to notify recipients around the time that meeting registration opens on March 12.</p> <p>Priority will be given to member applicants who are selected by the organizers to give a talk or poster. If we have fewer awardees presenting than we have travel award funds, then the remaining awards will be offered to non-presenting members who still plan to attend the Congress.</p> <p>We will be sure to notify you as soon as we can with decisions on these travel awards. And if you are chosen, please make sure you register early!</p> <p>Best wishes,</p> <p>Chris Caruso<br /> ASN Treasurer</p> <p>Andrea Case<br /> SSE Executive Vice President</p> Wed, 31 Jan 2018 06:00:00 GMT Ruth Patrick Student Poster Award http://amnat.org/announcements/ANNStuPosterWin.html Recipient of the Ruth Patrick Student Poster Award, January 2018, for her poster, "Specialist bee pollinators phenological matched with Clarkia blooming at the community level". &nbsp; The Ruth Patrick Student Poster Award was established in 2012 to recognize a&nbsp;student who has presented an outstanding poster at the annual meeting or at the stand-alone meeting of the American Society of Naturalists. Ruth Patrick&nbsp;was a renowned limnologist, past president of the&nbsp;American Society of Naturalists (1975), and Lifetime Honorary Member of the ASN. <p>Recipient of the Ruth Patrick Student Poster Award, January 2018, for her poster,<br /> &quot;Specialist bee pollinators phenological matched with Clarkia blooming at the community level&quot;.</p> <p>&nbsp;</p> <hr><p>The Ruth Patrick Student Poster Award was established in 2012 to recognize a&nbsp;student who has presented an outstanding poster at the annual meeting or at the stand-alone meeting of the American Society of Naturalists.</p> <p><a href="http://www.heinzawards.net/recipients/ruth-patrick">Ruth Patrick</a>&nbsp;was a renowned limnologist, past president of the&nbsp;American Society of Naturalists (1975), and Lifetime Honorary Member of the ASN.</p> Mon, 29 Jan 2018 06:00:00 GMT “Frequency-dependence and ecological drift shape coexistence of species with similar niches” http://amnat.org/an/newpapers/JuneSvensson.html The DOI will be https://dx.doi.org/10.1086/697201 Ecological drift, frequency-dependence and interference competition shape coexistence of species with similar niches A&nbsp;research team led by Professor Erik Svensson at Lund University (Sweden) decided to experimentally investigate how closely related but ecologically similar damselflies of the genus Calopteryx (“demoiselles”) could co-exist. The traditional explanation of why and how species co-exist are that they differ in their ecological niches, i. e. their resource use, habitats or their general way of living. This classical explanation suggest that species can co-exist without outcompeting each other, since each species might perform best in its own ecological niche, provided that niche differences between species are large. This traditional view has been challenged by the so-called neutral theory, which emphasize that many species are ecologically similar and are therefore unlikely to differ sufficiently in their ecological niches to be maintained over long time periods. According to neutral theory, species might instead go extinct for random reasons in a process called “ecological drift”, but there is limited empirical evidence for this process in nature. In Fennoscandia, two species of Calopteryx demoiselles co-exist: the banded demoiselle (Calopteryx splendens) and the beautiful demoiselle (C.&nbsp;virgo). These two species are ecologically and morphologically very similar and often co-occur along slow-flowing rivers. These two species have no strong differences in resource use, habitat choice, climatic niches or thermal preferences. Using a combination of field surveys at different localities in Scandinavia, density- and frequency-manipulations in large outdoor cages, field behavioral experiments on male-male interspecific aggression and simulation modelling, the research team showed that both ecological drift and a process called negative frequency-dependence (“rare species advantage”) shape the abundance and co-occurrence of these two closely related species. This study was performed between 2008 and 2015. These findings are important, because this is one of few documented empirical examples of ecological drift. The study shows that ecological drift can operate even if species are not completely neutral. Moreover, the mechanism of negative frequency-dependence can operate even if species do not differ strongly in their ecological niches, presumably because of interference competition and male-male aggression. These results therefore help us to understand the general problem of species co-existence with implications for how biodiversity is maintained which is important also in terms of conservation biology. Abstract The coexistence of ecologically similar species might be counteracted by ecological drift and demographic stochasticity, both of which erode local diversity. With niche differentiation, species can be maintained through performance trade-offs between environments, but trade-offs are difficult to invoke for species with similar ecological niches. Such similar species might then go locally extinct due to stochastic ecological drift but there is little empirical evidence for such processes. Previous studies have relied on biogeographical surveys and inferred process from pattern, while experimental field investigation of ecological drift are rare. Mechanisms preserving local species diversity, such as frequency-dependence (e. g. rare-species advantages), can oppose local ecological drift, but the combined effects of ecological drift and such counteracting forces have seldom been investigated. Here, we investigate mechanisms between coexistence of ecologically similar but strongly sexually differentiated damselfly species (Calopteryx virgo and C.&nbsp;splendens). Combining field surveys, behavioral observations, experimental manipulations of species frequencies and densities, and simulation modelling, we demonstrate that species coexistence is shaped by the opposing forces of ecological drift and negative frequency-dependence (rare species advantage), generated by interference competition. Stochastic and deterministic processes therefore jointly shape coexistence. The role of negative frequency-dependence in delaying the loss of ecologically similar species, such as those formed by sexual selection, should therefore be considered in community assembly, macroecology, macroevolution and biogeography. More forthcoming papers &raquo; <p><i>The DOI will be https://dx.doi.org/10.1086/697201 </i></p> <p><b>Ecological drift, frequency-dependence and interference competition shape coexistence of species with similar niches </b></p><p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">A</span>&nbsp;research team led by Professor Erik Svensson at Lund University (Sweden) decided to experimentally investigate how closely related but ecologically similar damselflies of the genus <i>Calopteryx</i> (“demoiselles”) could co-exist. </p><p>The traditional explanation of why and how species co-exist are that they differ in their ecological niches, i. e. their resource use, habitats or their general way of living. This classical explanation suggest that species can co-exist without outcompeting each other, since each species might perform best in its own ecological niche, provided that niche differences between species are large. This traditional view has been challenged by the so-called neutral theory, which emphasize that many species are ecologically similar and are therefore unlikely to differ sufficiently in their ecological niches to be maintained over long time periods. According to neutral theory, species might instead go extinct for random reasons in a process called “ecological drift”, but there is limited empirical evidence for this process in nature. </p><p>In Fennoscandia, two species of <i>Calopteryx</i> demoiselles co-exist: the banded demoiselle (<i>Calopteryx splendens</i>) and the beautiful demoiselle (<i>C.&nbsp;virgo</i>). These two species are ecologically and morphologically very similar and often co-occur along slow-flowing rivers. These two species have no strong differences in resource use, habitat choice, climatic niches or thermal preferences. Using a combination of field surveys at different localities in Scandinavia, density- and frequency-manipulations in large outdoor cages, field behavioral experiments on male-male interspecific aggression and simulation modelling, the research team showed that both ecological drift and a process called negative frequency-dependence (“rare species advantage”) shape the abundance and co-occurrence of these two closely related species. This study was performed between 2008 and 2015. </p><p>These findings are important, because this is one of few documented empirical examples of ecological drift. The study shows that ecological drift can operate even if species are not completely neutral. Moreover, the mechanism of negative frequency-dependence can operate even if species do not differ strongly in their ecological niches, presumably because of interference competition and male-male aggression. These results therefore help us to understand the general problem of species co-existence with implications for how biodiversity is maintained which is important also in terms of conservation biology. </p><hr /> <h3>Abstract</h3> <p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">T</span>he coexistence of ecologically similar species might be counteracted by ecological drift and demographic stochasticity, both of which erode local diversity. With niche differentiation, species can be maintained through performance trade-offs between environments, but trade-offs are difficult to invoke for species with similar ecological niches. Such similar species might then go locally extinct due to stochastic ecological drift but there is little empirical evidence for such processes. Previous studies have relied on biogeographical surveys and inferred process from pattern, while experimental field investigation of ecological drift are rare. Mechanisms preserving local species diversity, such as frequency-dependence (e. g. rare-species advantages), can oppose local ecological drift, but the combined effects of ecological drift and such counteracting forces have seldom been investigated. Here, we investigate mechanisms between coexistence of ecologically similar but strongly sexually differentiated damselfly species (<i>Calopteryx virgo</i> and <i>C.&nbsp;splendens</i>). Combining field surveys, behavioral observations, experimental manipulations of species frequencies and densities, and simulation modelling, we demonstrate that species coexistence is shaped by the opposing forces of ecological drift and negative frequency-dependence (rare species advantage), generated by interference competition. Stochastic and deterministic processes therefore jointly shape coexistence. The role of negative frequency-dependence in delaying the loss of ecologically similar species, such as those formed by sexual selection, should therefore be considered in community assembly, macroecology, macroevolution and biogeography. </p> <!-- <p><a href="https://dx.doi.org/10.1086/697201">Read&nbsp;the&nbsp;Article</a> </p> --> <div style="float: right;"><a href="http://www.amnat.org/an/newpapers.html"> <span style="font-size: large; font-family: Georgia;"><i>More forthcoming papers</i> &raquo;</span></a></div> Mon, 29 Jan 2018 06:00:00 GMT “Temporally autocorrelated environmental fluctuations inhibit the evolution of stress tolerance” http://amnat.org/an/newpapers/JuneWieczynski.html The DOI will be https://dx.doi.org/10.1086/697200 Adaptive responses to stress are controlled by environmental ‘color’ The biological world is constantly changing, introducing new challenges to which species must adapt. For example, climate change might increase the incidence of extreme events like heat waves or droughts. But will species be able to evolve adaptations to combat these new environmental challenges? In this study, Wieczynski et al. address this question and ask specifically whether the temporal structure of a fluctuating environment, a.k.a. ‘environmental color,’ can direct the course of evolution. The authors subject a model virus (bacteriophage ϕ6) to a range of environmental scenarios in the laboratory and compare these results to a suite of evolutionary models. They find that adaptations to tolerate environmental stress are more likely to occur in ‘whiter’ environments that rapidly fluctuate between harsh and benign conditions than in ‘redder’ environments in which these fluctuations are much slower, even when the total amount of stress stays the same. This result can be explained by a tradeoff – although stress tolerant individuals can withstand harsh conditions, they suffer reduced reproductive ability under benign conditions. Harsh events happen so frequently in ‘white’ environments that the cost of low reproduction during benign conditions is negligible. However, ‘redder’ environments create extended periods of benign conditions in which stress tolerant individuals are outcompeted by less tolerant, fast-growing individuals, meaning that the cost of low reproduction outweighs the advantage of stress tolerance in the long term. This work represents an important advance in understanding how species evolve in fluctuating environments and shows that the temporal structure of the environment can be an important factor controlling adaptation in response to environmental challenges. Abstract As global environmental conditions continue to change at an unprecedented rate many species will experience increases in natural and anthropogenic stress. Generally speaking, selection is expected to favor adaptations that reduce the negative impact of environmental stress (i.e., stress tolerance). However, natural environmental variables typically fluctuate, exhibiting various degrees of temporal autocorrelation, known as environmental ‘colors,’ which may complicate evolutionary responses to stress. Here we combine experiments and theory to show that temporal environmental autocorrelation can determine long-term evolutionary responses to stress, without affecting the total amount of stress experienced over time. Experimental evolution of RNA virus lineages in differing environmental autocorrelation treatments agreed closely with predictions from our theoretical models that stress tolerance is favored in less autocorrelated (whiter) environments but disfavored in more autocorrelated (redder) environments. This is explained by an interaction between environmental autocorrelation and a phenotypic tradeoff between stress tolerance and reproductive ability. The degree to which environmental autocorrelation influences evolutionary trajectories depends on the shape of this tradeoff as well as the relative level of tolerance exhibited by novel mutants. These results suggest that long-term evolutionary dynamics depend not only on the overall strength of selection, but also on the way that selection is distributed over time. More forthcoming papers &raquo; <p><i>The DOI will be https://dx.doi.org/10.1086/697200 </i></p> <p><b>Adaptive responses to stress are controlled by environmental ‘color’ </b></p><p><span style="line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-size: 40px; font-weight: bold; float: left;">T</span>he biological world is constantly changing, introducing new challenges to which species must adapt. For example, climate change might increase the incidence of extreme events like heat waves or droughts. But will species be able to evolve adaptations to combat these new environmental challenges? In this study, Wieczynski et al. address this question and ask specifically whether the temporal structure of a fluctuating environment, a.k.a. &lsquo;environmental color,&rsquo; can direct the course of evolution. The authors subject a model virus (bacteriophage ϕ6) to a range of environmental scenarios in the laboratory and compare these results to a suite of evolutionary models. They find that adaptations to tolerate environmental stress are more likely to occur in &lsquo;whiter&rsquo; environments that rapidly fluctuate between harsh and benign conditions than in &lsquo;redder&rsquo; environments in which these fluctuations are much slower, even when the total amount of stress stays the same. This result can be explained by a tradeoff &ndash; although stress tolerant individuals can withstand harsh conditions, they suffer reduced reproductive ability under benign conditions. Harsh events happen so frequently in &lsquo;white&rsquo; environments that the cost of low reproduction during benign conditions is negligible. However, &lsquo;redder&rsquo; environments create extended periods of benign conditions in which stress tolerant individuals are outcompeted by less tolerant, fast-growing individuals, meaning that the cost of low reproduction outweighs the advantage of stress tolerance in the long term. This work represents an important advance in understanding how species evolve in fluctuating environments and shows that the temporal structure of the environment can be an important factor controlling adaptation in response to environmental challenges.</p> <hr /> <h3>Abstract</h3> <p><span style="line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-size: 40px; font-weight: bold; float: left;">A</span>s global environmental conditions continue to change at an unprecedented rate many species will experience increases in natural and anthropogenic stress. Generally speaking, selection is expected to favor adaptations that reduce the negative impact of environmental stress (i.e., stress tolerance). However, natural environmental variables typically fluctuate, exhibiting various degrees of temporal autocorrelation, known as environmental &lsquo;colors,&rsquo; which may complicate evolutionary responses to stress. Here we combine experiments and theory to show that temporal environmental autocorrelation can determine long-term evolutionary responses to stress, without affecting the total amount of stress experienced over time. Experimental evolution of RNA virus lineages in differing environmental autocorrelation treatments agreed closely with predictions from our theoretical models that stress tolerance is favored in less autocorrelated (whiter) environments but disfavored in more autocorrelated (redder) environments. This is explained by an interaction between environmental autocorrelation and a phenotypic tradeoff between stress tolerance and reproductive ability. The degree to which environmental autocorrelation influences evolutionary trajectories depends on the shape of this tradeoff as well as the relative level of tolerance exhibited by novel mutants. These results suggest that long-term evolutionary dynamics depend not only on the overall strength of selection, but also on the way that selection is distributed over time.</p> <!-- <p><a href="https://dx.doi.org/10.1086/697200">Read&nbsp;the&nbsp;Article</a> </p> --> <div style="float: right;"><a href="http://www.amnat.org/an/newpapers.html"><span style="font-family: Georgia; font-size: large;"><i>More forthcoming papers</i> &raquo;</span></a></div> Mon, 29 Jan 2018 06:00:00 GMT “Eco-evolutionary buffering: rapid evolution facilitates regional species coexistence despite local priority effects” http://amnat.org/an/newpapers/JuneWittmann-A.html The DOI will be https://dx.doi.org/10.1086/697187 New hypothesis and model for coexistence in metacommunities with priority effects: eco-evolutionary buffering Abstract Inhibitory priority effects, in which early-arriving species exclude competing species from local communities, are thought to enhance regional species diversity via community divergence. Theory suggests, however, that these same priority effects make it difficult for species to coexist in the region unless individuals are continuously supplied from an external species pool, often an unrealistic assumption. Here we develop an eco-evolutionary hypothesis to solve this conundrum. We build a metacommunity model in which local priority effects occur between two species via interspecific interference. Within each species there are two genotypes: one is more resistant to interspecific interference than the other, but pays a fitness cost for its resistance. Because of this trade-off, species evolve to become less resistant as they become regionally more common. Rare species can then invade some local patches and consequently recover in regional frequency. This “eco-evolutionary buffering” enables the regional coexistence of species despite local priority effects, even in the absence of immigration from an external species pool. Our model predicts that eco-evolutionary buffering is particularly effective when local communities are small and connected by infrequent dispersal. More forthcoming papers &raquo; <p><i>The DOI will be https://dx.doi.org/10.1086/697187 </i></p> <p><b>New hypothesis and model for coexistence in metacommunities with priority effects: eco-evolutionary buffering </b></p><h3>Abstract</h3> <p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">I</span>nhibitory priority effects, in which early-arriving species exclude competing species from local communities, are thought to enhance regional species diversity via community divergence. Theory suggests, however, that these same priority effects make it difficult for species to coexist in the region unless individuals are continuously supplied from an external species pool, often an unrealistic assumption. Here we develop an eco-evolutionary hypothesis to solve this conundrum. We build a metacommunity model in which local priority effects occur between two species via interspecific interference. Within each species there are two genotypes: one is more resistant to interspecific interference than the other, but pays a fitness cost for its resistance. Because of this trade-off, species evolve to become less resistant as they become regionally more common. Rare species can then invade some local patches and consequently recover in regional frequency. This “eco-evolutionary buffering” enables the regional coexistence of species despite local priority effects, even in the absence of immigration from an external species pool. Our model predicts that eco-evolutionary buffering is particularly effective when local communities are small and connected by infrequent dispersal. </p> <!-- <p><a href="https://dx.doi.org/10.1086/697187">Read&nbsp;the&nbsp;Article</a> </p> --> <div style="float: right;"><a href="http://www.amnat.org/an/newpapers.html"> <span style="font-size: large; font-family: Georgia;"><i>More forthcoming papers</i> &raquo;</span></a></div> Mon, 29 Jan 2018 06:00:00 GMT Letter on Evolution 2018 http://amnat.org/announcements/ESEB.html Dear SSE, ASN and SSB members, As many of you are aware, the 2018 meetings are jointly sponsored by the Society for the Study of Evolution (SSE), the American Society of Naturalists (ASN), the Society for Systematic Biology (SSB), and the European Society for Evolutionary Biology (ESEB), with the goal of strengthening international networking and collaboration. The Joint Congress will be held in the beautiful coastal town of Montpellier, France, following the successful first Congress in Ottawa in 2012. Just as the first Joint Congress followed the North American meeting style, this Congress follows typical ESEB style, with, for example, limited presentations organized into topical symposia. We are incredibly thankful to ESEB for hosting this Congress and for their tremendous organizational efforts and financial support. We are delighted by the overwhelming interest in this year’s meeting, with over 3500 applications for talks and posters. However, concerns have been raised that the number of abstract submissions is many more than can be accommodated (800 talks and 1200 posters), which could lead to a large number of members being unable to present. We would like to emphasize that the numbers are difficult to gauge at this point, because abstracts can be submitted without cost or a commitment to attend. We also want to assure you that symposium organizers have been given strict instructions to diversify their speakers among a number of axes, from gender to career stage. Nevertheless, the number of submissions is certainly much larger than attendance at any of our meetings over the past decade (typical attendance at an Evolution Meeting is ~1500, with 2450 at the previous Joint Congress; www.evolutionmeetings.org/previous-meetings.html) and wasn’t anticipated. We apologize in advance if we are unable to accommodate everyone who wants to present. Please be assured that we will pay close attention to the numbers and adjust as needed for future meetings. &nbsp; Because this year’s meeting venue can accommodate 2500 attendees in total, if you would like to attend the Joint Congress, we strongly suggest that you register early. Meeting registration will open in mid-March; please stay tuned for more information about this. Sincerely, Hopi Hoekstra&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;Sharon Y. Strauss&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;Susana Magall&oacute;n SSE President&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;ASN President&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;SSB President &nbsp; <p>Dear SSE, ASN and SSB members,</p> <p>As many of you are aware, the 2018 meetings are jointly sponsored by the Society for the Study of Evolution (SSE), the American Society of Naturalists (ASN), the Society for Systematic Biology (SSB), and the European Society for Evolutionary Biology (ESEB), with the goal of strengthening international networking and collaboration. The Joint Congress will be held in the beautiful coastal town of Montpellier, France, following the successful first Congress in Ottawa in 2012.</p> <p>Just as the first Joint Congress followed the North American meeting style, this Congress follows typical ESEB style, with, for example, limited presentations organized into topical symposia. We are incredibly thankful to ESEB for hosting this Congress and for their tremendous organizational efforts and financial support.</p> <p>We are delighted by the overwhelming interest in this year&rsquo;s meeting, with over 3500 applications for talks and posters. However, concerns have been raised that the number of abstract submissions is many more than can be accommodated (800 talks and 1200 posters), which could lead to a large number of members being unable to present. We would like to emphasize that the numbers are difficult to gauge at this point, because abstracts can be submitted without cost or a commitment to attend. We also want to assure you that symposium organizers have been given strict instructions to diversify their speakers among a number of axes, from gender to career stage.</p> <p>Nevertheless, the number of submissions is certainly much larger than attendance at any of our meetings over the past decade (typical attendance at an Evolution Meeting is ~1500, with 2450 at the previous Joint Congress; www.evolutionmeetings.org/previous-meetings.html) and wasn&rsquo;t anticipated. We apologize in advance if we are unable to accommodate everyone who wants to present. Please be assured that we will pay close attention to the numbers and adjust as needed for future meetings. &nbsp;</p> <p>Because this year&rsquo;s meeting venue can accommodate 2500 attendees in total, if you would like to attend the Joint Congress, we strongly suggest that you register early. Meeting registration will open in mid-March; please stay tuned for more information about this.</p> <p><br /> Sincerely,</p> <p><br /> Hopi Hoekstra&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;Sharon Y. Strauss&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;Susana Magall&oacute;n<br /> SSE President&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;ASN President&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;SSB President</p> <p>&nbsp;</p> Tue, 23 Jan 2018 06:00:00 GMT “Phylo-allometric analyses showcase the interplay between life history patterns and phenotypic convergence in cleaner wrasses” http://amnat.org/an/newpapers/MayBaliga.html The DOI will be https://dx.doi.org/10.1086/697047 Ontogenetic trajectories of cleaner fishes are shaped by life history patterns of feeding ecology Juvenile animals often show stark differences in ecology from their adult counterparts; capitalizing on specific resources may only be favorable in a certain phase of life. This raises the question of how the process of development may adapt to meet shifting ecological demands. Identifying how ecology is intertwined with the evolution of ontogeny has long relied on between-species comparisons of how traits scale with body size. But, because morphological evolution occurs through modification of ancestral developmental patterns, many aspects of a species’ ontogeny may be due to retained ancestral recipes. This influence can constrain how traits evolve or cloud the signal of new adaptations. Therefore, how ontogeny evolves with ecology is an exciting arena of study for phylogenetic comparative methods, which can unravel historical vs. novel signals in evolutionary patterns. Vikram Baliga and Rita Mehta use the repeated evolution of cleaning behavior in the reef fish family Labridae (wrasses, parrotfishes) to understand how species can penetrate new ecological niches through adaptive changes to ontogeny. Cleaning is a mutualism wherein an individual (“cleaner”) feeds on ectoparasites living on other organisms. Remarkably, three-fourths of wrasses that clean do so predominately as juveniles, growing out of it (so to speak) as adults. The evolution of cleaning therefore provides a powerful opportunity to determine how ontogenetic shifts in feeding ecology can influence the evolution of scaling of musculoskeletal traits. Baliga and Mehta examine the ontogenetic scaling patterns of 33 labrid species and develop an approach in which the ontogenetic trajectories of taxa can be ordinated while accounting for shared ancestry. They show that the recurring evolution of juvenile-only cleaning behavior in the Labridae yields similar changes to developmental patterning. This research explicitly shows that scaling trajectories are evolutionarily labile and can adapt to changing ecological pressures over ontogeny, which expands our fundamental understanding of how phenotypic diversity is generated and maintained. Abstract Phenotypic convergence is a macroevolutionary pattern that need not be consistent across life history. Ontogenetic transitions in dietary specialization clearly illustrate the dynamics of ecological selection as organisms grow. The extent of phenotypic convergence among taxa that share a similar ecological niche may therefore vary ontogenetically. Because ontogenetic processes have been shown to evolve, phylogenetic comparative methods can be useful in examining how the scaling of traits relates to ecology. Cleaning, a behavior in which taxa consume ectoparasites off clientele, is well-represented among wrasses (Labridae). Nearly three-fourths of labrids that clean do so predominately as juveniles, transitioning away as adults. We examine the scaling patterns of 33 labrid species to understand how life history patterns of cleaning relate to ontogenetic patterns of phenotypic convergence. We find that as juveniles, cleaners exhibit convergence in body and cranial traits that enhance ectoparasitivory. We then find that taxa that transition away from cleaning exhibit ontogenetic trajectories that are distinct from those of other wrasses. Obligate and facultative species that continue to clean over ontogeny, however, maintain characteristics that are conducive to cleaning. Collectively, we find that life history patterns of cleaning behavior are concordant with ontogenetic patterns in phenotype in wrasses. More forthcoming papers &raquo; <p><i>The DOI will be https://dx.doi.org/10.1086/697047 </i></p> <p><b>Ontogenetic trajectories of cleaner fishes are shaped by life history patterns of feeding ecology </b></p><p><span style="line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-size: 40px; font-weight: bold; float: left;">J</span>uvenile animals often show stark differences in ecology from their adult counterparts; capitalizing on specific resources may only be favorable in a certain phase of life. This raises the question of how the process of development may adapt to meet shifting ecological demands. Identifying how ecology is intertwined with the evolution of ontogeny has long relied on between-species comparisons of how traits scale with body size. But, because morphological evolution occurs through modification of ancestral developmental patterns, many aspects of a species&rsquo; ontogeny may be due to retained ancestral recipes. This influence can constrain how traits evolve or cloud the signal of new adaptations. Therefore, how ontogeny evolves with ecology is an exciting arena of study for phylogenetic comparative methods, which can unravel historical vs. novel signals in evolutionary patterns.</p> <p>Vikram Baliga and Rita Mehta use the repeated evolution of cleaning behavior in the reef fish family Labridae (wrasses, parrotfishes) to understand how species can penetrate new ecological niches through adaptive changes to ontogeny. Cleaning is a mutualism wherein an individual (&ldquo;cleaner&rdquo;) feeds on ectoparasites living on other organisms. Remarkably, three-fourths of wrasses that clean do so predominately as juveniles, growing out of it (so to speak) as adults. The evolution of cleaning therefore provides a powerful opportunity to determine how ontogenetic shifts in feeding ecology can influence the evolution of scaling of musculoskeletal traits.</p> <p>Baliga and Mehta examine the ontogenetic scaling patterns of 33 labrid species and develop an approach in which the ontogenetic trajectories of taxa can be ordinated while accounting for shared ancestry. They show that the recurring evolution of juvenile-only cleaning behavior in the Labridae yields similar changes to developmental patterning. This research explicitly shows that scaling trajectories are evolutionarily labile and can adapt to changing ecological pressures over ontogeny, which expands our fundamental understanding of how phenotypic diversity is generated and maintained.</p> <hr /> <h3>Abstract</h3> <p><span style="line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-size: 40px; font-weight: bold; float: left;">P</span>henotypic convergence is a macroevolutionary pattern that need not be consistent across life history. Ontogenetic transitions in dietary specialization clearly illustrate the dynamics of ecological selection as organisms grow. The extent of phenotypic convergence among taxa that share a similar ecological niche may therefore vary ontogenetically. Because ontogenetic processes have been shown to evolve, phylogenetic comparative methods can be useful in examining how the scaling of traits relates to ecology. Cleaning, a behavior in which taxa consume ectoparasites off clientele, is well-represented among wrasses (Labridae). Nearly three-fourths of labrids that clean do so predominately as juveniles, transitioning away as adults. We examine the scaling patterns of 33 labrid species to understand how life history patterns of cleaning relate to ontogenetic patterns of phenotypic convergence. We find that as juveniles, cleaners exhibit convergence in body and cranial traits that enhance ectoparasitivory. We then find that taxa that transition away from cleaning exhibit ontogenetic trajectories that are distinct from those of other wrasses. Obligate and facultative species that continue to clean over ontogeny, however, maintain characteristics that are conducive to cleaning. Collectively, we find that life history patterns of cleaning behavior are concordant with ontogenetic patterns in phenotype in wrasses.</p> <!-- <p> <a href="https://dx.doi.org/10.1086/697047">Read&nbsp;the&nbsp;Article</a> </p> --> <div style="float: right;"><a href="http://www.amnat.org/an/newpapers.html"><span style="font-family: Georgia; font-size: large;"><i>More forthcoming papers</i> &raquo;</span></a></div> Thu, 18 Jan 2018 06:00:00 GMT “Tipping points in resource abundance drives irreversible changes in community structure” http://amnat.org/an/newpapers/MayHaney.html The DOI will be https://dx.doi.org/10.1086/697045 Extreme changes in resources can cause irreversible shifts in community structure – a tipping point Global climate change has made what were seemingly extraordinary environmental conditions, such as prolonged droughts, heat waves, and extreme precipitation events commonplace. Such extremes in environmental fluctuation can cause critical changes in the resources available to vulnerable species. How might such extreme changes impact the stability of ecological communities? In this new study, Seth D. Haney and Adam M. Siepielski use mathematical modeling to show that extreme changes in resources can cause irreversible evolutionary changes and critical shifts in communities. They find that while small to moderate changes in resource abundance have little effect on ecological and evolutionary dynamics, when resource scarcities are sufficiently extreme, a critical transition—a tipping point—occurs. This causes consumer traits to diverge and restructures the community in a way that outlasts the resource scarcity. Therefore, even though traits can readily evolve in response to minor resource fluctuations, large environmental shifts may be the dominant driver of long-lasting impacts on community structure. Past changes in environmental conditions can thus lock community structure up, unless a large-magnitude perturbation occurs. These results shed new light on the potential long-term impacts caused by climate change on ecological communities. Abstract Global climate change has made what were seemingly extraordinary environmental conditions, such as prolonged droughts, commonplace. One consequence of extreme environmental change is concomitant changes in resource abundance. How will such extreme resource changes impact biodiversity? We developed a trait-based consumer-resource model to examine how resource abundance affects the potential for adaptive evolution and coexistence among competitors. We found that moderate changes in resource abundance have little effect on trait evolution. However, when resource scarcities were sufficiently extreme, a critical transition–a tipping point–occurred, which caused consumer traits to diverge and re-structured the community in a way that outlasted the scarcity. Therefore, even though traits can evolve in response to minor resource fluctuations, large environmental shifts may be necessary for producing long-lasting impacts on community structure. These results may also help to illuminate patterns of stasis frequently observed in nature, despite the considerable evidence demonstrating rapid evolutionary change. More forthcoming papers &raquo; <p><i>The DOI will be https://dx.doi.org/10.1086/697045 </i></p> <p><b>Extreme changes in resources can cause irreversible shifts in community structure &ndash; a tipping point </b></p><p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">G</span>lobal climate change has made what were seemingly extraordinary environmental conditions, such as prolonged droughts, heat waves, and extreme precipitation events commonplace. Such extremes in environmental fluctuation can cause critical changes in the resources available to vulnerable species. How might such extreme changes impact the stability of ecological communities? </p> <p>In this new study, Seth D. Haney and Adam M. Siepielski use mathematical modeling to show that extreme changes in resources can cause irreversible evolutionary changes and critical shifts in communities. They find that while small to moderate changes in resource abundance have little effect on ecological and evolutionary dynamics, when resource scarcities are sufficiently extreme, a critical transition—a tipping point—occurs. This causes consumer traits to diverge and restructures the community in a way that outlasts the resource scarcity. Therefore, even though traits can readily evolve in response to minor resource fluctuations, large environmental shifts may be the dominant driver of long-lasting impacts on community structure. Past changes in environmental conditions can thus lock community structure up, unless a large-magnitude perturbation occurs. These results shed new light on the potential long-term impacts caused by climate change on ecological communities. </p> <hr /> <h3>Abstract</h3> <p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">G</span>lobal climate change has made what were seemingly extraordinary environmental conditions, such as prolonged droughts, commonplace. One consequence of extreme environmental change is concomitant changes in resource abundance. How will such extreme resource changes impact biodiversity? We developed a trait-based consumer-resource model to examine how resource abundance affects the potential for adaptive evolution and coexistence among competitors. We found that moderate changes in resource abundance have little effect on trait evolution. However, when resource scarcities were sufficiently extreme, a critical transition–a tipping point–occurred, which caused consumer traits to diverge and re-structured the community in a way that outlasted the scarcity. Therefore, even though traits can evolve in response to minor resource fluctuations, large environmental shifts may be necessary for producing long-lasting impacts on community structure. These results may also help to illuminate patterns of stasis frequently observed in nature, despite the considerable evidence demonstrating rapid evolutionary change. </p> <!-- <p><a href="https://dx.doi.org/10.1086/697045">Read&nbsp;the&nbsp;Article</a> </p> --> <div style="float: right;"><a href="http://www.amnat.org/an/newpapers.html"> <span style="font-size: large; font-family: Georgia;"><i>More forthcoming papers</i> &raquo;</span></a></div> Thu, 18 Jan 2018 06:00:00 GMT “Fifty years of Mountain Passes: A perspective on Dan Janzen’s classic paper” http://amnat.org/an/newpapers/MaySheldon-A.html The DOI will be https://dx.doi.org/10.1086/697046 50 years on, Dan Janzen's “Mountain Passes” continues to inform a remarkable diversity of ecological work Abstract In 1967, Dan Janzen published “Why Mountain Passes Are Higher In The Tropics” in The American Naturalist. Janzen’s seminal paper has captured the attention of generations of biologists and continues to inspire theoretical and empirical work. The underlying assumptions and derived predictions are broadly synthetic and widely applicable. Consequently, “Janzen’s Seasonality Hypothesis” has proven relevant to physiology, climate change, ecology, and evolution. To celebrate the 50th anniversary of this highly influential paper, we highlight the past, present, and future of this work, and include a unique, historical perspective from Janzen himself. More forthcoming papers &raquo; <p><i>The DOI will be https://dx.doi.org/10.1086/697046 </i></p> <p><b>50 years on, Dan Janzen's “Mountain Passes” continues to inform a remarkable diversity of ecological work </b></p><h3>Abstract</h3> <p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">I</span>n 1967, Dan Janzen published “Why Mountain Passes Are Higher In The Tropics” in The American Naturalist. Janzen’s seminal paper has captured the attention of generations of biologists and continues to inspire theoretical and empirical work. The underlying assumptions and derived predictions are broadly synthetic and widely applicable. Consequently, “Janzen’s Seasonality Hypothesis” has proven relevant to physiology, climate change, ecology, and evolution. To celebrate the 50th anniversary of this highly influential paper, we highlight the past, present, and future of this work, and include a unique, historical perspective from Janzen himself. </p> <!-- <p><a href="https://dx.doi.org/10.1086/697046">Read&nbsp;the&nbsp;Article</a> </p> --> <div style="float: right;"><a href="http://www.amnat.org/an/newpapers.html"> <span style="font-size: large; font-family: Georgia;"><i>More forthcoming papers</i> &raquo;</span></a></div> Thu, 18 Jan 2018 06:00:00 GMT “Species pool functional diversity plays a hidden role in generating β-diversity” http://amnat.org/an/newpapers/MayPatrick.html The DOI will be https://dx.doi.org/10.1086/696978 Functional diversity of the species pool contributes to spatial variation in community composition With global extinction rates continuing to accelerate, understanding the factors that generate and maintain biological diversity is imperative for conservation and ecosystem management. Chris Patrick at Texas A&M University–Corpus Christi and Bryan Brown at Virginia Tech University recently found evidence that the size of the functional differences among species in the species pool may be a vital missing piece of the larger biodiversity puzzle. β-diversity, the variation in the identities of species among different habitats, is an important part of biological diversity that bridges the biological diversity within local habitats and the number of species in regional species pools. While the size of species pool and habitat heterogeneity are considered important predictors of β-diversity, individual studies often produce conflicting results about the relative importance of these drivers. Using invertebrate communities found in the Mid-Atlantic streams of the United States as a study system, Patrick and Brown found that after accounting for environmental heterogeneity and species pool size, watersheds with species pools with high functional diversity tend to have higher β-diversity. This transformative finding supports the existence of a link between functional diversity and β-diversity. Understanding this link will enhance our theoretical understanding of processes that generate biological diversity at landscape scales and provide avenues for methodological advances in metacommunity analysis. The result will help reconcile prior research on drivers of β-diversity and has applications across ecosystems and is important for both advancing ecological theory and providing new avenues of research for landscape scale conservation management. Abstract Functional trait diversity is used as a way to infer mechanistic processes that drive community assembly. While functional diversity within communities is often viewed as a response variable, here we present and test a framework for how functional diversity among taxa in the regional species pool drive the assembly of communities among habitats. We predicted that species pool functional diversity should work with environmental heterogeneity to drive &beta;-diversity. We tested these predictions by modeling empirical patterns in invertebrate communities from 570 streams in 52 watersheds. Our analysis of the field data provided strong support for the inclusion of both functional diversity and environmental heterogeneity in the models, and our predictions were supported when the community was analyzed all together. However, analyses within individual functional feeding guilds revealed strong context dependency in the relative importance of functional diversity, &gamma;-richness, and environmental heterogeneity on &beta;-diversity. We interpret the results to mean that functional diversity can play an important role in driving &beta;-diversity; however, within guilds the nature of interspecific interactions and species pool size complicate the relationship. Future research should test this conceptual model across different ecosystems and in experimental settings using metacommunity mecocosms to enhance our understanding the role that functional variation plays in generating spatial biodiversity patterns. More forthcoming papers &raquo; <p><i>The DOI will be https://dx.doi.org/10.1086/696978 </i> </p> <p><b>Functional diversity of the species pool contributes to spatial variation in community composition </b></p><p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">W</span>ith global extinction rates continuing to accelerate, understanding the factors that generate and maintain biological diversity is imperative for conservation and ecosystem management. Chris Patrick at Texas A&M University–Corpus Christi and Bryan Brown at Virginia Tech University recently found evidence that the size of the functional differences among species in the species pool may be a vital missing piece of the larger biodiversity puzzle. β-diversity, the variation in the identities of species among different habitats, is an important part of biological diversity that bridges the biological diversity within local habitats and the number of species in regional species pools. While the size of species pool and habitat heterogeneity are considered important predictors of β-diversity, individual studies often produce conflicting results about the relative importance of these drivers. </p><p>Using invertebrate communities found in the Mid-Atlantic streams of the United States as a study system, Patrick and Brown found that after accounting for environmental heterogeneity and species pool size, watersheds with species pools with high functional diversity tend to have higher β-diversity. This transformative finding supports the existence of a link between functional diversity and β-diversity. Understanding this link will enhance our theoretical understanding of processes that generate biological diversity at landscape scales and provide avenues for methodological advances in metacommunity analysis. The result will help reconcile prior research on drivers of β-diversity and has applications across ecosystems and is important for both advancing ecological theory and providing new avenues of research for landscape scale conservation management. </p><h3>Abstract</h3> <p><span style="line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-size: 40px; font-weight: bold; float: left;">F</span>unctional trait diversity is used as a way to infer mechanistic processes that drive community assembly. While functional diversity within communities is often viewed as a response variable, here we present and test a framework for how functional diversity among taxa in the regional species pool drive the assembly of communities among habitats. We predicted that species pool functional diversity should work with environmental heterogeneity to drive &beta;-diversity. We tested these predictions by modeling empirical patterns in invertebrate communities from 570 streams in 52 watersheds. Our analysis of the field data provided strong support for the inclusion of both functional diversity and environmental heterogeneity in the models, and our predictions were supported when the community was analyzed all together. However, analyses within individual functional feeding guilds revealed strong context dependency in the relative importance of functional diversity, &gamma;-richness, and environmental heterogeneity on &beta;-diversity. We interpret the results to mean that functional diversity can play an important role in driving &beta;-diversity; however, within guilds the nature of interspecific interactions and species pool size complicate the relationship. Future research should test this conceptual model across different ecosystems and in experimental settings using metacommunity mecocosms to enhance our understanding the role that functional variation plays in generating spatial biodiversity patterns. <!-- <a href="https://dx.doi.org/10.1086/696978">Read&nbsp;the&nbsp;Article</a> --></p> <div style="float: right;"><a href="http://www.amnat.org/an/newpapers.html"><span style="font-family: Georgia; font-size: large;"><i>More forthcoming papers</i> &raquo;</span></a></div> Wed, 17 Jan 2018 06:00:00 GMT “Class structure, demography, and selection: reproductive-value weighting in non-equilibrium, polymorphic populations” http://amnat.org/an/newpapers/MayLion.html The DOI will be https://dx.doi.org/10.1086/696976 Dynamical reproductive values to study the interplay of demography and selection in class-structured populations Nearly 90 years ago, Ronald A. Fisher introduced the concept of reproductive value in his seminal book, The Genetical Theory of Natural Selection. Fisher defined reproductive value as the relative contribution of individuals of a given age to the future of the population. He further suggested that, when evaluating the consequences of natural selection, individuals should be weighted by their reproductive value. This idea proved influential and reproductive value has since become a central concept of evolutionary theory. It is routinely used when analyzing populations structured into different classes (such as age groups, developmental stages, habitats, or sexes). In theoretical models, reproductive values are generally calculated in populations that have very simple dynamics or are at equilibrium. In this article by Sébastien Lion of the Centre National pour la Recherche Scientifique in Montpellier, new theory is developed that shows how Fisher's seminal idea can be extended to analyze populations with more complex ecological dynamics, provided each individual is weighted by a time-dependent reproductive value. With this weighting, the effect of natural selection can always be separated from the effect of demographic transitions. Indeed, to calculate the relevant reproductive values, the theory shows that we can ignore genetic variation and focus on the aggregate demographic dynamics of the population. This could prove useful for analyzing empirical data where the underlying genetic variation of a trait is unknown. At a more conceptual level, this research shows that a dynamical and demographic definition of reproductive values allows evolution to be described through a simple Price equation in which demography and selection are neatly separated. Abstract In natural populations, individuals of a given genotype may belong to different classes. Such classes can represent different age groups, developmental stages, or habitats. Class structure has important evolutionary consequences because the fitness of individuals with the same genetic background may vary depending on their class. As a result, demographic transitions between classes can cause fluctuations in the trait mean that need to be removed when estimating selection on a trait. Intrinsic differences between classes are classically taken into account by weighting individuals by class-specific reproductive values, defined as the relative contribution of individuals in a given class to the future of the population. These reproductive values are generally constant weights calculated from a constant projection matrix. Here, I show, for large populations and clonal reproduction, that reproductive values can be defined as time-dependent weights satisfying dynamical demographic equations that only depend on the average between-class transition rates over all genotypes. Using these time-dependent demographic reproductive values yields a simple Price equation where the non-selective effects of between-class transitions are removed from the dynamics of the trait. This generalises previous theory to a large class of ecological scenarios, taking into account density-dependence, ecological feedbacks, arbitrary strength of selection and arbitrary trait distributions. I discuss the role of reproductive values for prospective and retrospective analyses of the dynamics of phenotypic traits. More forthcoming papers &raquo; <p><i>The DOI will be https://dx.doi.org/10.1086/696976 </i></p> <p><b>Dynamical reproductive values to study the interplay of demography and selection in class-structured populations </b></p><p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">N</span>early 90 years ago, Ronald A. Fisher introduced the concept of reproductive value in his seminal book, <i>The Genetical Theory of Natural Selection</i>. Fisher defined reproductive value as the relative contribution of individuals of a given age to the future of the population. He further suggested that, when evaluating the consequences of natural selection, individuals should be weighted by their reproductive value. This idea proved influential and reproductive value has since become a central concept of evolutionary theory. It is routinely used when analyzing populations structured into different classes (such as age groups, developmental stages, habitats, or sexes). </p> <p>In theoretical models, reproductive values are generally calculated in populations that have very simple dynamics or are at equilibrium. In this article by Sébastien Lion of the Centre National pour la Recherche Scientifique in Montpellier, new theory is developed that shows how Fisher's seminal idea can be extended to analyze populations with more complex ecological dynamics, provided each individual is weighted by a time-dependent reproductive value. With this weighting, the effect of natural selection can always be separated from the effect of demographic transitions. Indeed, to calculate the relevant reproductive values, the theory shows that we can ignore genetic variation and focus on the aggregate demographic dynamics of the population. This could prove useful for analyzing empirical data where the underlying genetic variation of a trait is unknown. At a more conceptual level, this research shows that a dynamical and demographic definition of reproductive values allows evolution to be described through a simple Price equation in which demography and selection are neatly separated. </p> <hr /> <h3>Abstract</h3> <p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">I</span>n natural populations, individuals of a given genotype may belong to different classes. Such classes can represent different age groups, developmental stages, or habitats. Class structure has important evolutionary consequences because the fitness of individuals with the same genetic background may vary depending on their class. As a result, demographic transitions between classes can cause fluctuations in the trait mean that need to be removed when estimating selection on a trait. Intrinsic differences between classes are classically taken into account by weighting individuals by class-specific reproductive values, defined as the relative contribution of individuals in a given class to the future of the population. These reproductive values are generally constant weights calculated from a constant projection matrix. Here, I show, for large populations and clonal reproduction, that reproductive values can be defined as time-dependent weights satisfying dynamical demographic equations that only depend on the average between-class transition rates over all genotypes. Using these time-dependent demographic reproductive values yields a simple Price equation where the non-selective effects of between-class transitions are removed from the dynamics of the trait. This generalises previous theory to a large class of ecological scenarios, taking into account density-dependence, ecological feedbacks, arbitrary strength of selection and arbitrary trait distributions. I discuss the role of reproductive values for prospective and retrospective analyses of the dynamics of phenotypic traits. </p> <!-- <p> <a href="https://dx.doi.org/10.1086/696976">Read&nbsp;the&nbsp;Article</a> </p> --> <div style="float: right;"><a href="http://www.amnat.org/an/newpapers.html"> <span style="font-size: large; font-family: Georgia;"><i>More forthcoming papers</i> &raquo;</span></a></div> Wed, 17 Jan 2018 06:00:00 GMT “Oxygen limitation at the larval stage and the evolution of maternal investment per offspring in aquatic environments” http://amnat.org/an/newpapers/MayRollinson.html The DOI will be http://dx.doi.org/10.1086/696857 Maternal effects on body size are constrained in aquatic systems by O2 transport in larvae, not by the geometry of eggs In aquatic environments, a common observation is that mothers produce small eggs under warm conditions, a pattern that loosely comprises part of the well-known “temperature-size rule”. For decades, it was emphasized that oxygen limitation may drive this pattern in ectotherms: small eggs and embryos evolve in warm environments because metabolic rate of the embryo is high, and large eggs with low surface-area-to-volume ratios would become oxygen-limited. More recently, however, this idea has been turned on its head, as several studies have suggested that egg size per se does not influence the availability of oxygen to embryos, mainly because embryonic oxygen consumption increases with egg size more slowly than does the surface area of the egg that is available for gas exchange. Why then might egg size, and hence maternal investment per offspring, decrease as environmental temperature increases? Drawing from hundreds of amphibian species across two major clades, the authors use comparative methods to show that oxygen limitation at the larval stage, not the egg stage, helps explain variation in investment per offspring in aquatic environments. Large larvae may be oxygen limited because respiratory features, such as gills, are underdeveloped in early life, resulting in diffusive cutaneous oxygen uptake as a primary means of sustaining aerobic activity during a life stage where predation risk is high. This work helps extend the generality of temperature-dependent oxygen limitation as a mechanism driving the temperature-size rule in aquatic systems. Abstract Oxygen limitation and surface-area-to-volume relationships of the egg were long thought to constrain egg size in aquatic environments, but more recent evidence indicates that egg size per se does not influence oxygen availability to embryos. Here, we suggest that investment per offspring is nevertheless constrained in aquatic anamniotes, by virtue of oxygen transport in free-living larvae. Drawing on the well-supported assumption that oxygen limitation is relatively pronounced in aquatic vs terrestrial environments, and that oxygen limitation is particularly severe in warm aquatic environments, we employ comparative methods in the Amphibia to investigate this problem. Across hundreds of species and two major amphibian clades, the slope of species-mean egg diameter over habitat temperature is negative for species with aquatic larvae, but is positive or neutral for species featuring terrestrial eggs and no larvae. Yet, across species with aquatic larvae, the negative slope of egg diameter over temperature is similar whether eggs are laid terrestrially or aquatically, consistent with an oxygen constraint arising at the larval stage. Finally, egg size declines more strongly with temperature for species that cannot breathe aerially prior to metamorphosis, compared to those that can. Our results suggest oxygen transport in larvae, not eggs, constrains investment per offspring. This study further extends the generality of temperature-dependent oxygen limitation as a mechanism driving the temperature-size rule in aquatic systems. More forthcoming papers &raquo; <p><i>The DOI will be http://dx.doi.org/10.1086/696857 </i></p> <p><b>Maternal effects on body size are constrained in aquatic systems by O<span class="font-size:70%; position:relative; bottom:-0.3em;">2</span> transport in larvae, not by the geometry of eggs </b></p><p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">I</span>n aquatic environments, a common observation is that mothers produce small eggs under warm conditions, a pattern that loosely comprises part of the well-known “temperature-size rule”. For decades, it was emphasized that oxygen limitation may drive this pattern in ectotherms: small eggs and embryos evolve in warm environments because metabolic rate of the embryo is high, and large eggs with low surface-area-to-volume ratios would become oxygen-limited. More recently, however, this idea has been turned on its head, as several studies have suggested that egg size per se does not influence the availability of oxygen to embryos, mainly because embryonic oxygen consumption increases with egg size more slowly than does the surface area of the egg that is available for gas exchange. Why then might egg size, and hence maternal investment per offspring, decrease as environmental temperature increases? Drawing from hundreds of amphibian species across two major clades, the authors use comparative methods to show that oxygen limitation at the larval stage, not the egg stage, helps explain variation in investment per offspring in aquatic environments. Large larvae may be oxygen limited because respiratory features, such as gills, are underdeveloped in early life, resulting in diffusive cutaneous oxygen uptake as a primary means of sustaining aerobic activity during a life stage where predation risk is high. This work helps extend the generality of temperature-dependent oxygen limitation as a mechanism driving the temperature-size rule in aquatic systems. </p> <hr /> <h3>Abstract</h3> <p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">O</span>xygen limitation and surface-area-to-volume relationships of the egg were long thought to constrain egg size in aquatic environments, but more recent evidence indicates that egg size per se does not influence oxygen availability to embryos. Here, we suggest that investment per offspring is nevertheless constrained in aquatic anamniotes, by virtue of oxygen transport in free-living larvae. Drawing on the well-supported assumption that oxygen limitation is relatively pronounced in aquatic vs terrestrial environments, and that oxygen limitation is particularly severe in warm aquatic environments, we employ comparative methods in the Amphibia to investigate this problem. Across hundreds of species and two major amphibian clades, the slope of species-mean egg diameter over habitat temperature is negative for species with aquatic larvae, but is positive or neutral for species featuring terrestrial eggs and no larvae. Yet, across species with aquatic larvae, the negative slope of egg diameter over temperature is similar whether eggs are laid terrestrially or aquatically, consistent with an oxygen constraint arising at the larval stage. Finally, egg size declines more strongly with temperature for species that cannot breathe aerially prior to metamorphosis, compared to those that can. Our results suggest oxygen transport in larvae, not eggs, constrains investment per offspring. This study further extends the generality of temperature-dependent oxygen limitation as a mechanism driving the temperature-size rule in aquatic systems. </p> <!-- <p><a href="http://dx.doi.org/10.1086/696857">Read&nbsp;the&nbsp;Article</a> </p> --> <div style="float: right;"><a href="http://www.amnat.org/an/newpapers.html"> <span style="font-size: large; font-family: Georgia;"><i>More forthcoming papers</i> &raquo;</span></a></div> Tue, 02 Jan 2018 06:00:00 GMT “The consequences of polyandry for sibship structures, distributions of relationships and relatedness, and potential for inbreeding in a wild population” http://amnat.org/an/newpapers/MayGermain.html The DOI will be http://dx.doi.org/10.1086/696855 Female mating with multiple males reduces inbreeding potential among her offspring In many species, females produce broods or litters of offspring with multiple fathers, but the actual benefits of this behavior (known as ‘polyandry’) remain largely unknown. One potential benefit could be that producing offspring with several males changes the degree to which a female’s descendants are related and could potentially mate with a relative (‘inbreed’) in the future. Because inbreeding can have severely negative consequences for any resulting offspring, theory predicts that the overall risk of inbreeding within a population should be lower when females produce offspring with multiple males. However, to date, no study has determined the actual effects of this process in wild populations with complex reproductive systems, such as females producing multiple broods or litters with the same or different males over their lifetimes, or where males themselves mate with multiple females. In this study, researchers at the University of Aberdeen and the University of British Columbia used a long-term, island study population of Song Sparrows (Melospiza melodia) to determine the consequences of polyandry for inbreeding risk in future generations. Song sparrows form social pair-bonds where females and males cooperate to raise offspring, but DNA analysis reveals that about 28% of chicks in the population are fathered by a male other than their mother’s social mate. By comparing the actual genetic relatedness among all potential mates in the population with their relatedness had females only produced offspring with their social mate, this study finds that polyandry reduces the chances of inbreeding among close relatives (like full siblings) in future generations, but actually increases the chances of inbreeding among more distant relatives (like half-siblings). The overall conclusion of the study is that while polyandry can lead to some degree of reduced inbreeding in the future, thereby providing a benefit to this behavior, different aspects of mating systems in wild populations can substantially change this effect from what we would expect. Abstract The evolutionary benefits of simultaneous polyandry (female multiple mating within a single reproductive event) remain elusive. One potential benefit could arise if polyandry alters sibship structures and consequent relationships and relatedness among females’ descendants, and thereby intrinsically reduces future inbreeding risk (the ‘indirect inbreeding avoidance hypothesis’). However such effects have not been quantified in naturally complex mating systems that also encompass iteroparity, overlapping generations, sequential polyandry, and polygyny. We used long-term social and genetic pedigree data from song sparrows (Melospiza melodia) to quantify cross-generational consequences of simultaneous polyandry for offspring sibship structures and distributions of relationships and relatedness among possible mates. Simultaneous polyandry decreased full-sibships and increased half-sibships on average, but such effects varied among females and were smaller than would occur in the absence of sequential polyandry or polygyny. Further, while simultaneous polyandry decreased the overall frequencies of possible matings among adult full-sibs, it increased the frequencies of possible matings among adult half-sibs and more distant relatives. These results imply that the intrinsic consequences of simultaneous polyandry for inbreeding risk could cause weak indirect selection on polyandry, but the magnitude and direction of such effects will depend on complex interactions with other mating system components and the form of inbreeding depression. More forthcoming papers &raquo; <p><i>The DOI will be http://dx.doi.org/10.1086/696855 </i> </p> <p><b>Female mating with multiple males reduces inbreeding potential among her offspring </b></p><p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">I</span>n many species, females produce broods or litters of offspring with multiple fathers, but the actual benefits of this behavior (known as ‘polyandry’) remain largely unknown. One potential benefit could be that producing offspring with several males changes the degree to which a female’s descendants are related and could potentially mate with a relative (‘inbreed’) in the future. Because inbreeding can have severely negative consequences for any resulting offspring, theory predicts that the overall risk of inbreeding within a population should be lower when females produce offspring with multiple males. However, to date, no study has determined the actual effects of this process in wild populations with complex reproductive systems, such as females producing multiple broods or litters with the same or different males over their lifetimes, or where males themselves mate with multiple females. </p><p>In this study, researchers at the University of Aberdeen and the University of British Columbia used a long-term, island study population of Song Sparrows (<i>Melospiza melodia</i>) to determine the consequences of polyandry for inbreeding risk in future generations. Song sparrows form social pair-bonds where females and males cooperate to raise offspring, but DNA analysis reveals that about 28% of chicks in the population are fathered by a male other than their mother’s social mate. By comparing the actual genetic relatedness among all potential mates in the population with their relatedness had females only produced offspring with their social mate, this study finds that polyandry reduces the chances of inbreeding among close relatives (like full siblings) in future generations, but actually increases the chances of inbreeding among more distant relatives (like half-siblings). The overall conclusion of the study is that while polyandry can lead to some degree of reduced inbreeding in the future, thereby providing a benefit to this behavior, different aspects of mating systems in wild populations can substantially change this effect from what we would expect. </p> <hr /> <h3>Abstract</h3> <p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">T</span>he evolutionary benefits of simultaneous polyandry (female multiple mating within a single reproductive event) remain elusive. One potential benefit could arise if polyandry alters sibship structures and consequent relationships and relatedness among females’ descendants, and thereby intrinsically reduces future inbreeding risk (the ‘indirect inbreeding avoidance hypothesis’). However such effects have not been quantified in naturally complex mating systems that also encompass iteroparity, overlapping generations, sequential polyandry, and polygyny. We used long-term social and genetic pedigree data from song sparrows (<i>Melospiza melodia</i>) to quantify cross-generational consequences of simultaneous polyandry for offspring sibship structures and distributions of relationships and relatedness among possible mates. Simultaneous polyandry decreased full-sibships and increased half-sibships on average, but such effects varied among females and were smaller than would occur in the absence of sequential polyandry or polygyny. Further, while simultaneous polyandry decreased the overall frequencies of possible matings among adult full-sibs, it increased the frequencies of possible matings among adult half-sibs and more distant relatives. These results imply that the intrinsic consequences of simultaneous polyandry for inbreeding risk could cause weak indirect selection on polyandry, but the magnitude and direction of such effects will depend on complex interactions with other mating system components and the form of inbreeding depression. </p> <!-- <p><a href="http://dx.doi.org/10.1086/696855">Read&nbsp;the&nbsp;Article</a> </p> --> <div style="float: right;"><a href="http://www.amnat.org/an/newpapers.html"> <span style="font-size: large; font-family: Georgia;"><i>More forthcoming papers</i> &raquo;</span></a></div> Tue, 02 Jan 2018 06:00:00 GMT “Selfing can facilitate transitions between pollination syndromes” http://amnat.org/an/newpapers/MayWessinger-A.html The DOI will be http://dx.doi.org/10.1086/696856 A population genetic model suggests delayed selfing can facilitate transitions to hummingbird pollination Abstract Pollinator-mediated selection on plants can favor transitions to a new pollinator depending on the relative abundances and efficiencies of pollinators present in the community. A frequently observed example is the transition from bee pollination to hummingbird pollination. We present a population genetic model that examines whether the ability to inbreed can influence evolutionary change in traits that underlie pollinator attraction. We find that a transition to a more efficient, but less abundant pollinator is favored under a broadened set of ecological conditions if plants are capable of delayed selfing rather than obligately outcrossing. Delayed selfing allows plants carrying an allele that attracts the novel pollinator to reproduce even when this pollinator is rare, providing reproductive assurance. In addition, delayed selfing weakens the effects of Haldane's sieve by increasing the fixation probability for recessive alleles that confer adaptation to the new pollinator. Our model provides novel insight into the paradoxical abundance of recessive mutations in adaptation to hummingbird attraction. It further predicts that transitions to efficient but less abundant pollinators (such as hummingbirds in certain communities) should disproportionately occur in self-compatible lineages. Currently available mating system datasets are consistent with this prediction and we suggest future areas of research that will enable a rigorous test of this theory. More forthcoming papers &raquo; <p><i>The DOI will be http://dx.doi.org/10.1086/696856 </i> </p> <p><b>A population genetic model suggests delayed selfing can facilitate transitions to hummingbird pollination </b></p><h3>Abstract</h3> <p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">P</span>ollinator-mediated selection on plants can favor transitions to a new pollinator depending on the relative abundances and efficiencies of pollinators present in the community. A frequently observed example is the transition from bee pollination to hummingbird pollination. We present a population genetic model that examines whether the ability to inbreed can influence evolutionary change in traits that underlie pollinator attraction. We find that a transition to a more efficient, but less abundant pollinator is favored under a broadened set of ecological conditions if plants are capable of delayed selfing rather than obligately outcrossing. Delayed selfing allows plants carrying an allele that attracts the novel pollinator to reproduce even when this pollinator is rare, providing reproductive assurance. In addition, delayed selfing weakens the effects of Haldane's sieve by increasing the fixation probability for recessive alleles that confer adaptation to the new pollinator. Our model provides novel insight into the paradoxical abundance of recessive mutations in adaptation to hummingbird attraction. It further predicts that transitions to efficient but less abundant pollinators (such as hummingbirds in certain communities) should disproportionately occur in self-compatible lineages. Currently available mating system datasets are consistent with this prediction and we suggest future areas of research that will enable a rigorous test of this theory. </p> <!-- <p><a href="http://dx.doi.org/10.1086/696856">Read&nbsp;the&nbsp;Article</a> </p> --> <div style="float: right;"><a href="http://www.amnat.org/an/newpapers.html"> <span style="font-size: large; font-family: Georgia;"><i>More forthcoming papers</i> &raquo;</span></a></div> Tue, 02 Jan 2018 06:00:00 GMT “Maternal effects in a wild songbird are environmentally plastic but only marginally alter the rate of adaptation” http://amnat.org/an/newpapers/MayRamakers.html The DOI will be http://dx.doi.org/10.1086/696847 Bridging the gap between theory and data: Plastic maternal effect in wild bird has limited potential to affect adaptation Genes are not the only source of resemblance between you and your parents. Imagine, for example, how the amount of care that a mother provides influences the condition of her offspring or, more indirectly, how the number of offspring within the brood influences this condition through sibling competition. If the size of a brood negatively influences the condition of each individual offspring, this may create the odd situation where offspring that inherit genes for producing many offspring may actually produce few offspring; this is because they are in a poor condition, as a direct result from growing up with many siblings. We call this a negative maternal effect (NME). Ramakers and colleagues (2018) wondered: if the environment worsens, making raising many offspring difficult, can a population respond by producing fewer offspring, or is it inhibited in doing so because of NMEs? Looking at clutch size in a small woodland bird, the great tit (Parus major), in the Netherlands, they used long-term field observations, experiments, and predictive modelling to predict how populations would respond in case of an environmental change—for the better or the worse—and how NMEs may facilitate or hamper this response. They showed that NMEs indeed exist in the great tit but that in the long run, according to the predictive model, their effect is too small to make a difference in how rapidly a population can respond to new environments. Their work emphasizes that predictive models are important in understanding evolutionary processes, but they need to be backed up by data from actual populations to keep them realistic. Abstract Despite ample evidence for the presence of maternal effects (MEs) in a variety of traits, and strong theoretical indications for their evolutionary consequences, empirical evidence to what extent MEs can influence evolutionary responses to selection remains ambiguous. We tested the degree to which MEs can alter the rate of adaptation of a key life-history trait, clutch size, using an individual-based model approach parameterized with experimental data from a long-term study of great tits (Parus major). We modelled two types of MEs: (i) an environmentally plastic ME, in which the relationship between maternal and offspring clutch size depended on the maternal environment via offspring condition, and (ii) a ‘fixed’ ME, in which this relationship was constant. Although both types of ME affected the rate of adaptation following an abrupt environmental shift, the overall effects were small. We conclude that evolutionary consequences of MEs are modest at best in our study system, at least for the trait and the particular type of ME we considered here. A closer link between theoretical and empirical work on MEs would hence be useful to obtain accurate predictions about the evolutionary consequences of MEs more generally. More forthcoming papers &raquo; <p><i>The DOI will be http://dx.doi.org/10.1086/696847 </i> </p> <p><b>Bridging the gap between theory and data: Plastic maternal effect in wild bird has limited potential to affect adaptation </b></p><p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">G</span>enes are not the only source of resemblance between you and your parents. Imagine, for example, how the amount of care that a mother provides influences the condition of her offspring or, more indirectly, how the number of offspring within the brood influences this condition through sibling competition. If the size of a brood negatively influences the condition of each individual offspring, this may create the odd situation where offspring that inherit genes for producing many offspring may actually produce few offspring; this is because they are in a poor condition, as a direct result from growing up with many siblings. We call this a negative maternal effect (NME). Ramakers and colleagues (2018) wondered: if the environment worsens, making raising many offspring difficult, can a population respond by producing fewer offspring, or is it inhibited in doing so because of NMEs? Looking at clutch size in a small woodland bird, the great tit (<i>Parus major</i>), in the Netherlands, they used long-term field observations, experiments, and predictive modelling to predict how populations would respond in case of an environmental change—for the better or the worse—and how NMEs may facilitate or hamper this response. They showed that NMEs indeed exist in the great tit but that in the long run, according to the predictive model, their effect is too small to make a difference in how rapidly a population can respond to new environments. Their work emphasizes that predictive models are important in understanding evolutionary processes, but they need to be backed up by data from actual populations to keep them realistic.</p> <hr /> <h3>Abstract</h3> <p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">D</span>espite ample evidence for the presence of maternal effects (MEs) in a variety of traits, and strong theoretical indications for their evolutionary consequences, empirical evidence to what extent MEs can influence evolutionary responses to selection remains ambiguous. We tested the degree to which MEs can alter the rate of adaptation of a key life-history trait, clutch size, using an individual-based model approach parameterized with experimental data from a long-term study of great tits (<i>Parus major</i>). We modelled two types of MEs: (i) an environmentally plastic ME, in which the relationship between maternal and offspring clutch size depended on the maternal environment via offspring condition, and (ii) a ‘fixed’ ME, in which this relationship was constant. Although both types of ME affected the rate of adaptation following an abrupt environmental shift, the overall effects were small. We conclude that evolutionary consequences of MEs are modest at best in our study system, at least for the trait and the particular type of ME we considered here. A closer link between theoretical and empirical work on MEs would hence be useful to obtain accurate predictions about the evolutionary consequences of MEs more generally. </p> <!-- <p><a href="http://dx.doi.org/10.1086/696847">Read&nbsp;the&nbsp;Article</a> </p> --> <div style="float: right;"><a href="http://www.amnat.org/an/newpapers.html"> <span style="font-size: large; font-family: Georgia;"><i>More forthcoming papers</i> &raquo;</span></a></div> Tue, 02 Jan 2018 06:00:00 GMT “Host traits drive viral life histories across phytoplankton viruses” http://amnat.org/an/newpapers/MayEdwards-A.html The DOI will be http://dx.doi.org/10.1086/696849 Burst size and latent period across diverse phytoplankton viruses can be explained in terms of life history evolution Abstract Viruses are integral to ecological and evolutionary processes, but we have a poor understanding of what drives variation in key traits across diverse viruses. For lytic viruses, burst size, latent period, and genome size are primary characteristics controlling host-virus dynamics. Here we synthesize data on these traits for 75 strains of phytoplankton viruses, which play an important role in global biogeochemistry. We find that primary traits of the host (genome size, growth rate) explain 40-50% of variation in burst size and latent period. Specifically, burst size and latent period both exhibit saturating relationships vs. the host:virus genome size ratio, with both traits increasing at low genome size ratios while showing no relationship at high size ratios. In addition, latent period declines as host growth rate increases. We analyze a model of latent period evolution to explore mechanisms that could cause these patterns. The model predicts that burst size may often be set by the host genomic resources available for viral construction, while latent period evolves to permit this maximal burst size, modulated by host metabolic rate. These results suggest that general mechanisms may underlie the evolution of diverse viruses. Future extensions of this work could help explain viral regulation of host populations, viral influence on community structure and diversity, and viral roles in biogeochemical cycles. More forthcoming papers &raquo; <p><i>The DOI will be http://dx.doi.org/10.1086/696849 </i></p> <p><b>Burst size and latent period across diverse phytoplankton viruses can be explained in terms of life history evolution </b></p><h3>Abstract</h3> <p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">V</span>iruses are integral to ecological and evolutionary processes, but we have a poor understanding of what drives variation in key traits across diverse viruses. For lytic viruses, burst size, latent period, and genome size are primary characteristics controlling host-virus dynamics. Here we synthesize data on these traits for 75 strains of phytoplankton viruses, which play an important role in global biogeochemistry. We find that primary traits of the host (genome size, growth rate) explain 40-50% of variation in burst size and latent period. Specifically, burst size and latent period both exhibit saturating relationships vs. the host:virus genome size ratio, with both traits increasing at low genome size ratios while showing no relationship at high size ratios. In addition, latent period declines as host growth rate increases. We analyze a model of latent period evolution to explore mechanisms that could cause these patterns. The model predicts that burst size may often be set by the host genomic resources available for viral construction, while latent period evolves to permit this maximal burst size, modulated by host metabolic rate. These results suggest that general mechanisms may underlie the evolution of diverse viruses. Future extensions of this work could help explain viral regulation of host populations, viral influence on community structure and diversity, and viral roles in biogeochemical cycles. </p> <!-- <p><a href="http://dx.doi.org/10.1086/696849">Read&nbsp;the&nbsp;Article</a> </p> --> <div style="float: right;"><a href="http://www.amnat.org/an/newpapers.html"> <span style="font-size: large; font-family: Georgia;"><i>More forthcoming papers</i> &raquo;</span></a></div> Tue, 02 Jan 2018 06:00:00 GMT “Overdispersed spatial patterning of dominant bunchgrasses in southeastern pine savannas” http://amnat.org/an/newpapers/MayHovanes-A.html The DOI will be http://dx.doi.org/10.1086/696834 Bunchgrasses are spatially overdispersed in pine savannas; this may affect population, community, and ecosystem dynamics Abstract Spatial patterning is a key natural history attribute of sessile organisms that frequently emerges from and dictates potential for interactions among organisms. We tested whether bunchgrasses, the dominant plant functional group in longleaf pine savanna groundcover communities, are non-randomly patterned by characterizing the spatial dispersion of three bunchgrass species across six sites in Louisiana and Florida. We mapped bunchgrass tussocks > 5.0-cm basal diameter in three 3×3-m plots in each site. We modeled tussocks as two-dimensional objects to analyze their spatial relationships while preserving sizes and shapes of individual tussocks. Tussocks were overdispersed (more regularly spaced than random) for all species and sites at the local interaction scale (<&nbsp;0.3&nbsp;m). This general pattern likely arises from a tussock-centered, distance-dependent mechanism e.g., inter-tussock competition. Non-random spatial patterns of dominant species have implications for community assembly and ecosystem function in tussock-dominated grasslands and savannas, including those characterized by extreme biodiversity. More forthcoming papers &raquo; <p><i>The DOI will be http://dx.doi.org/10.1086/696834 </i></p> <p><b>Bunchgrasses are spatially overdispersed in pine savannas; this may affect population, community, and ecosystem dynamics </b></p><h3>Abstract</h3> <p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">S</span>patial patterning is a key natural history attribute of sessile organisms that frequently emerges from and dictates potential for interactions among organisms. We tested whether bunchgrasses, the dominant plant functional group in longleaf pine savanna groundcover communities, are non-randomly patterned by characterizing the spatial dispersion of three bunchgrass species across six sites in Louisiana and Florida. We mapped bunchgrass tussocks > 5.0-cm basal diameter in three 3×3-m plots in each site. We modeled tussocks as two-dimensional objects to analyze their spatial relationships while preserving sizes and shapes of individual tussocks. Tussocks were overdispersed (more regularly spaced than random) for all species and sites at the local interaction scale (<&nbsp;0.3&nbsp;m). This general pattern likely arises from a tussock-centered, distance-dependent mechanism e.g., inter-tussock competition. Non-random spatial patterns of dominant species have implications for community assembly and ecosystem function in tussock-dominated grasslands and savannas, including those characterized by extreme biodiversity. </p> <!-- <p><a href="http://dx.doi.org/10.1086/696834">Read&nbsp;the&nbsp;Article</a> </p> --> <div style="float: right;"><a href="http://www.amnat.org/an/newpapers.html"> <span style="font-size: large; font-family: Georgia;"><i>More forthcoming papers</i> &raquo;</span></a></div> Tue, 02 Jan 2018 06:00:00 GMT “Intraspecific variation in learning: worker wasps are less able to learn and remember individual conspecific faces than queen wasps” http://amnat.org/an/newpapers/MayTibbetts-A.html The DOI will be http://dx.doi.org/10.1086/696848 Worker paper wasps have lower individual recognition ability than queens, even though castes are flexible Abstract Research on individual recognition often focuses on species-typical recognition abilities rather than assessing intraspecific variation in recognition. As individual recognition is cognitively costly, the capacity for recognition may vary within species. We test how individual face recognition differs between nest-founding queens (foundresses) and workers in Polistes fuscatus paper wasps. Individual recognition mediates dominance interactions among foundresses. Three previously published experiments have shown that foundresses (1) benefit by advertising their identity with distinctive facial patterns that facilitate recognition, (2) have robust memories of individuals, and 3)rapidly learn to distinguish between face images. Like foundresses, workers have variable facial patterns and are capable of individual recognition. However, worker dominance interactions are muted. Therefore, individual recognition may be less important for workers than foundresses. We find: (1) workers with unique faces receive similar amounts of aggression as workers with common faces, indicating that wasps do not benefit from advertising their individual identity with a unique appearance, (2) workers lack robust memories for individuals, as they cannot remember unique conspecifics after a six-day separation and (3) workers learn to distinguish between facial images more slowly than foundresses during training. The recognition differences between foundresses and workers are notable because Polistes lack discrete castes; foundresses and workers are morphologically similar and workers can take over as queens. Overall, social benefits and receiver capacity for individual recognition are surprisingly plastic. More forthcoming papers &raquo; <p><i>The DOI will be http://dx.doi.org/10.1086/696848 </i> </p> <p><b>Worker paper wasps have lower individual recognition ability than queens, even though castes are flexible </b></p><h3>Abstract</h3> <p><span style="float: left; font-size: 40px; line-height: 25px; padding-top: 4px; padding-right: 2px; padding-left: 2px; font-family: Garamond; font-weight: bold;">R</span>esearch on individual recognition often focuses on species-typical recognition abilities rather than assessing intraspecific variation in recognition. As individual recognition is cognitively costly, the capacity for recognition may vary within species. We test how individual face recognition differs between nest-founding queens (foundresses) and workers in <i>Polistes fuscatus</i> paper wasps. Individual recognition mediates dominance interactions among foundresses. Three previously published experiments have shown that foundresses (1) benefit by advertising their identity with distinctive facial patterns that facilitate recognition, (2) have robust memories of individuals, and 3)rapidly learn to distinguish between face images. Like foundresses, workers have variable facial patterns and are capable of individual recognition. However, worker dominance interactions are muted. Therefore, individual recognition may be less important for workers than foundresses. We find: (1) workers with unique faces receive similar amounts of aggression as workers with common faces, indicating that wasps do not benefit from advertising their individual identity with a unique appearance, (2) workers lack robust memories for individuals, as they cannot remember unique conspecifics after a six-day separation and (3) workers learn to distinguish between facial images more slowly than foundresses during training. The recognition differences between foundresses and workers are notable because <i>Polistes</i> lack discrete castes; foundresses and workers are morphologically similar and workers can take over as queens. Overall, social benefits and receiver capacity for individual recognition are surprisingly plastic. </p> <!-- <p> <a href="http://dx.doi.org/10.1086/696848">Read&nbsp;the&nbsp;Article</a> </p> --> <div style="float: right;"><a href="http://www.amnat.org/an/newpapers.html"> <span style="font-size: large; font-family: Georgia;"><i>More forthcoming papers</i> &raquo;</span></a></div> Tue, 02 Jan 2018 06:00:00 GMT