I study the role of rapid evolutionary changes in a spatial context, particularly for range expansions of invasive species and in climate-induced range shifts. Rapid evolution of dispersal ability can increase both the speed and variability of range expansions of invasive species, complicating conservation efforts. However, this same process has the potential to increase the ability of populations to track changing climatic conditions, which could greatly reduce projected biodiversity loss due to climate change. In my research, I combine laboratory microcosms with theoretical models to better understand the eco-evolutionary dynamics of moving populations and the contexts in which rapid evolution can help or hinder conservation efforts.
Office: Aven Nelson 130 Email: cweissle[at]uwyo[dot]edu Download my cv
John Benning, Postdoc
John studies species' range limits, adaptation, and the ecology and evolution of species' interactions. He began his position as a NSF Postdoctoral Fellow with the Weiss-Lehman and Hufbauer (Colorado State University) labs in September 2020 after finishing his PhD at the University of Minnesota. During his dissertation, he used manipulative field and greenhouse experiments to test how biotic and abiotic gradients influence the range limit of a California annual plant, Clarkia xantiana. While these experiments helped to dissect the proximate, ecological causes of range limits, they did not address the ultimate evolutionary phenomena underlying distributional limits. To that end, during his postdoc, he will use experimental evolution, genomic analyses, and novel models to test key predictions of range limit theory and build a conceptual model of how spatio-temporal environmental variation interacts with dispersal to influence adaptation and the formation of species' range boundaries. email: jwbenning[at]gmail[dot]com website: johnbenning.net
Spencer Holtz, PhD student
Spencer's research stems from his love of the natural world, and interest in the evolutionary dynamics of different species, specifically looking at them from a genetic perspective. He's excited by the advent of new genetic technologies that allow for new studies that will give us a much more in depth understanding of evolutionary processes. He's motivated by the idea of being able to use these experimental findings to inform conservation efforts to protect the natural world that he has been fascinated by his whole life. He graduated from the University of Colorado in Boulder in 2016 with a degree in biology, where he used next-gen genetic sequencing to study the metapopulation dynamics of the American pika, in order to see how they are responding to climate change. He started his PhD at UW in 2020, and his current research broadly encompasses the genetic effects of range shifts that are very common in the world today due to anthropogenic effects such as climate change, habitat destruction, and the introduction of new species. email: sholtz1[at]uwyo[dot]edu
Kaylee Hawkins, Undergraduate student
Kaylee is an undergraduate student pursuing a degree in Zoology with a minor in Wildlife and Fisheries Biology and Management. After graduation she plans on either pursing a job involving insects or amphibians whether that be with Fish and Wildlife or in a private conservation setting. Outside of academia she enjoys hiking with her dog and spending time at home hand embroidering, backstitching, and crocheting.
Alex Kissonergis, Undergraduate student
Alex is an undergraduate pursuing a B.S. in Biology. Though interested in many fields of science, invertebrates and pollinators piqued his interest from a young age. Post-graduation he hopes to pursue research in graduate school involving these interesting organisms. Outside of science he enjoys backcountry skiing, climbing, and biking.
email: akissone[at]uwyo[dot]edu
Lab Alumni
Cath Bowler
Cath received her PhD from the University of Queensland in 2022 and was co-supervised by Margie Mayfield, Lauren Shoemaker, and Christopher Weiss-Lehman.
For her dissertation, Cath developed models in a Bayesian framework to estimate competitive and facilitative species interactions that consider variation arising from demographic stochasticity. Additionally, she investigated how these distributions of species interactions can be used to develop probability distributions of coexistence in natural plant communities. More broadly, she is also interested in investigating the importance of non-additive species interactions in plant communities, whilst keeping in mind the logistic challenges of working with parameter heavy models and their potential translation to applied fields such as restoration ecology. Cath now works as an environmental consultant in Australia.
Bre Powers
Bre has a background in spatial ecology, natural resource management, landscape ecology, and community ecology. Her research, generally, has focused on understanding how climate or land-use/land-cover change, and land management techniques affect population dynamics or ecosystem service supply. Before joining the Weiss-Lehman lab at the University of Wyoming, Bre held a postdoctoral position at Boise State University, where she used spatially-explicit individual-based model to understand how climate change affects the phenology of migratory birds. She obtained her Ph.D. from the University of Auckland where she studied different assessment approaches of ecosystem services at a catchment scale using multi-modeling approaches. At UW, Bre worked with the Modelscape group to help understand how to increase predictability of models for species range expansions using eco-evo approaches. Bre not only has a passion for understanding the natural world, but also has a passion for exploring it and can be found adventuring around with her husband on the river, a mountain, rock face, or trail. She is now an Assistant Professor of Teaching in the School of Forestry at Northern Arizona University.
Chhaya Werner
Chhaya joined the University of Wyoming as part of the Modelscape project. She is interested in the role of stochasticity and variability on the dynamics of ecological communities. She received her PhD from UC Davis in 2018, where her research focused on the role of weather variation and priority affects in community assembly after disturbance and restoration. Following her PhD, she held a postdoc at the iDiv biodiversity research center in Germany, where she focused on species’ recruitment patterns under interacting global changes. As part of the Modelscape group, Chhaya developed computational and statistical approaches to multi-dimensional data in community ecology, with the goal of building predictive and mechanistic models for multi-species communities. She is now an assistant professor at Southern Oregon University
Sully is an undergraduate working towards a major in animal science. She has also declared a minor in molecular biology. After receiving her animal science degree, she hopes to attend vet school to further her education of veterinary medicine. She hopes to become a large animal vet and to own her own practice. She enjoys playing hockey on the UW women’s hockey team and skiing during the winter months.
Annaliese Bronner
Annaliese Bronner graduated from UW with her BA in Microbiology in 2021. Originally from Colorado Springs, she has always had an interest in science which grew into a passion during her time as a teaching assistant for General Chemistry.
Anna Carpenter
Anna is an undergraduate at the University of Wyoming, majoring in microbiology. She plans on attending veterinary school and opening a rural, large and small animal veterinary practice one day. She enjoys all things science, but also love the outdoors, adventuring, poetry, traveling, and riding horses.