Chairs
Professor Doug Emlen, University of Montana, USA
Professor Doug Emlen, University of Montana, USA
Douglas J Emlen studied at Cornell University (BA 1989), Princeton University (PhD 1994), and Duke University (Postdoctoral Research Fellow 1994-1997), before joining the faculty at the University of Montana where he is now the director of Organismal Biology, Ecology, and Evolution, one of UM’s three Programs of National Distinction. He is the first scholar from any Montana institution to be elected to the American Academy of Arts and Sciences (2016) and was the first Montanan to receive the U.S. Presidential Early Career Award in Science and Engineering (2002). Emlen has earned more than $2.5 million in multiple research awards from the National Science Foundation, including their five-year CAREER award, as well as a Young Investigator Prize and the E. O. Wilson Naturalist Award from the American Society of Naturalists. In 2014 he was awarded UM’s Distinguished Teaching Award, and in 2015 the Carnegie/CASE Professor of the Year Award for the State of Montana. His book Animal Weapons: The Evolution of Battle (Henry Holt, 2014) won the Phi Beta Kappa science book award in 2015, and his textbook Evolution: Making Sense of Life (co-authored with award-winning journalist Carl Zimmer, Macmillan Publishing, 2nd edition 2015), is presently adopted by more than 250 universities and colleges. His research has been featured in The New York Times, National Public Radio’s Fresh Air and Science Friday, and YouTube’s SciShow. This spring he starred in a BBC documentary about his work, Nature’s Wildest Weapons.
09:00-09:30
Sexually dimorphic structures in mammals: can we use them to draw inference about past environments?
Professor Christine Janis, University of Bristol, UK
Abstract
The pattern of sexual dimorphism in ungulate (hoofed) mammals in relation to habitat preference was established by Peter Jarman in the early 1970s. He proposed five categories of ecomorphology within African antelopes that related to body size, size dimorphism, and dimorphism in horns. These ecomorphologies were correlated with differences in reproductive behaviour, which in turn were correlated with habitats ranging from closed forest to open grasslands. Thus the distribution of such ecomorphologies within fossil communities may provide information about the habitat independent of other palaeoenvironmental proxies. While sexual dimorphism in body size is difficult to determine in fossils, absolute body size and patterns of the possession of horns (or other types of cranial appendages) can be observed. The pattern of acquisition of cranial appendages and changes in lineages over time can provide information about habitat changes both within and between geographic areas. Cranial appendages first appeared in artiodactyls in the mid Cenozoic at a time when more open habitats started to spread in the higher latitudes: but patterns of acquisition and distribution of dimorphic ecomorphologies differ between ungulates in North America and the Old World, implying earlier and more significant aridity on the North American continent (an implication now confirmed by other proxies). Patterns of horn dimorphism in African bovids may serve to illuminate habitat change over time on that continent.
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Professor Christine Janis, University of Bristol, UK
Professor Christine Janis, University of Bristol, UK
Christine has a BSc Natural Sciences (Zoology) from the University of Cambridge,a PhD in Organismal Biology (Vertebrate Paleontology) from Harvard University. and a Fellowship from Newnham College (University of Cambridge) Fellowship. She is a Professor of Ecology and Evolutionary Biology at Brown University, Providence, USA from 1983 – 2016 (full professor since 1999). Currently she is a Professor Emerita at Brown University, and Honorary Professor in Earth Sciences (Palaeobiology) at the University of Bristol. UK.
Her interests have primarily been in the evolution and palaeobiology of mammals, especially ungulates (hoofed mammals), although she has also published papers on the palaeobiology of early tetrapods and dinosaurs, and recently has come to have a penchant for marsupials (especially kangaroos and large carnivores). Her research is based in functional morphology, comparing the osteology of extinct mammals with extant ones in order to determine their probable behaviour, and she is also interested in how climatic and environmental change over the past 20 million years has affected the course of mammalian evolution.
09:45-10:15
Sexual selection on colour signals: mechanisms and diversity
Associate Professor Devi Stuart-Fox, University of Melbourne, Australia
Abstract
Sexual dichromatism, the difference between the sexes in coloration, is one of the most widely used indices of sexual selection in macroevolutionary studies. These studies have revealed evolutionary drivers of the strength of sexual selection, patterns of evolutionary losses and gains of sexual dichromatism, and associations between sexual dichromatism and rates of diversification (including speciation and/or extinction). But how robust is sexual dichromatism as a measure of sexual selection? What are the pitfalls and strengths of this measure? Measures of sexual dichromatism vary widely, limiting our ability to directly compare results between studies, and most do not account for receiver vision. This is important, both because animal colour vision varies substantially, and because the relationship between coloration and signal salience is likely non-linear. Colour is also produced by a variety of mechanisms, for example, pigmentary and structural. This has important implications for costs and constraints on colour variation, and therefore it is utility as a measure of sexual selection. Mechanisms of colour production also have implications for our ability to measure or reconstruct coloration of preserved and fossil specimens. Sexual dichromatism is a useful measure of the strength of sexual selection to identify patterns in the history of life, but coloration is multifaceted and must be understood in its biological context.
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Associate Professor Devi Stuart-Fox, University of Melbourne, Australia
Associate Professor Devi Stuart-Fox, University of Melbourne, Australia
Devi Stuart-Fox is an Associate Professor in the School of Biosciences at the University of Melbourne, Australia. Her research focuses on the evolution of animal coloration, particularly on macro-evolutionary patterns of diversity in animal coloration, and on the evolution of colour polymorphism and colour change. Stuart-Fox obtained her PhD at the University of Queensland, Australia in 2003 before spending four years at the University of the Witwatersrand in South Africa pursuing postdoctoral research on colour change in chameleons. She was an Australian Research Council Fellow from 2010-2015 and a Fellow at the Wissenschaftskolleg zu Berlin (Berlin Institute for Advanced Studies) in 2016.
11:00-11:30
Variation rates as an indication of sociosexual display in horned dinosaurs, and other ornithischians
Dr Caleb Brown, Royal Tyrrell Museum, Canada
Abstract
Phenotypic variation is the basic material upon which selection acts, and as such quantifying this variation is an important aspect of evolutionary biology. Specifically, research on a diverse array of living animals has documented higher rates of morphological variation in sociosexual display structures, than those under natural selection.
Many dinosaur species, particularly ornithischians, exhibit ‘exaggerated’ skeletal structures that lack obvious mechanical functions and have been hypothesized to have function is sexual and social display. These are often manifested as outgrowths/hypertrophy of the skull roof, including the solid and hollow crests of Hadrosauridae, the horns and frills of Ceratopsia, and the thickened domes of Pachycephalosauria. For dinosaur palaeobiology, however, intraspecific variation is often regarded as merely an obstacle to robust taxonomy.
Here morphological variation was quantified (using coefficient of variation) for the well-sampled species of horned dinosaur Centrosaurus apertus, as well as complementary dataset of the horned dinosaurs Anchiceratops, Chasmosaurus, Protoceratops, and the duck-billed dinosaurs Lambeosaurus, and Corythosaurus.
Levels of variation for the putative ornamentation structures (e.g. frills, horns, crests) are significantly higher (~2-3 times) than those for the remainder of the skull. These results are consistent with, and often statistically indistinguishable from, the known sexual displays of a comprehensive dataset of extant amniotes analogues (including mammals, birds, and squamates).
When combined with previous research suggesting these same structures in ornithischians are ontogenetically delayed, positively allometric, rapidly evolving, and highly species-specific, these data provide further support to the hypothesis that sociosexual selection was the evolutionary driver of these ‘exaggerated’ structures.
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Dr Caleb Brown, Royal Tyrrell Museum, Canada
Dr Caleb Brown, Royal Tyrrell Museum, Canada
Growing up in Alberta, Canada, Caleb was exposed to the province’s rich fossil history early, which sparked his interest in palaeontology and natural history. He received a B.Sc. and MSc from the University of Calgary in zoology and palaeontology, and then travelled east, to pursue my PhD at the University of Toronto and Royal Ontario Museum where he investigated the evolution of horned dinosaurs. Following is PhD, Caleb returned to his home province, to take up a post-doctoral fellowship at the Royal Tyrrell Museum of Palaeontology in Drumheller, Alberta, where his research focuses on Late Cretaceous ornithischian dinosaurs. Caleb’s research interests include investigating evolutionary rates, growth, and variation of dinosaur display structures (horns, frills and crests), and adding to the growing understanding of dinosaur diversity through ongoing fieldwork and excavations.
11:45-12:15
Sexual selection, adaptation and extinction: lessons from experimental evolution
Professor Jacek Radwan, Adam Mickiewicz University in Poznan, Poland
Abstract
Failure of populations to adapt to sudden environmental changes may lead to extinction. Sexual selection can have multiple, and often opposing, influences on extinction probability. Whether the net outcome of these influences is increased, or decreased, extinction risk is an open empirical question. Professor Radwan will demonstrate how experimental evolution can be used to address this question, focusing on his own work utilising mite species with males differing in expression of a costly sexually selected trait.
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Professor Jacek Radwan, Adam Mickiewicz University in Poznan, Poland
Professor Jacek Radwan, Adam Mickiewicz University in Poznan, Poland
Jacek Radwan received his PhD at Jagiellonian University, Krakow, Poland, where, after post-docs at the University of Sheffied, UK, and Max Planck Institute in Seewiesen, Germany, he become lecturer and then professor. Five years ago he moved to Poznan, to take up a position of Professor in Evolutionary Biology at Adam Mickiewicz University. His research have focused sexual selection, especially its evolutionary-genetic background, including the role of mutations and genes interacting with parasites, such as MHC genes. He has studied consequences of sexual selection for adaptation and extinction of populations using experimental evolution approach. Evolution of MHC genes and their role in biological conservation has recently become another important area of his research.