The Dillon Lab
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Michael Dillon, Principal Investigator

Professor & L. Floyd Clarke Chair, Department of Zoology & Physiology and Program in Ecology and Evolution at the University of Wyoming. I am a broadly trained integrative organismal biologist primarily interested in the interplay between organism physiology and the abiotic environment. In particular, mountains provide striking abiotic gradients matched by fascinating organismal responses; I spend a lot of time running up and down mountains chasing (mostly) insects. See Research and Publications and here is a (hopefully) up-to-date CV .


I received my BS in Biology from North Dakota State University in 2019 and worked for the USDA in Fargo ND as a lab technician for a semester before starting my masters degree here at UWYO. My undergraduate studies focused on the effects of agrochemicals on reproductive physiology of male honeybees. I continued my interested in reproductive physiology at the USDA and developed strategies for cryopreservation of bumblebee spermatozoa. As a second-year master’s student, my work is focused on how climate change may affect the reproductive physiology of male and queen bumblebees. My goal is to understand how extreme temperatures (warm or cold) may alter mating interactions between males and females and the viability of gametes. Alongside my bench and field work, I am passionate about science communication and education. I love teaching small humans about bees and getting them excited about science!


I received my BS in Zoology from the University of Washington.  Since then I have worked as a research and diagnostic laboratory technician, specializing in molecular biology techniques.  My current work focuses on macronutrient measurements of diapausing bumblebee queens.


I received a BS in Biology through the University of Wyoming at Casper program the fall of 2018. My previous research experience was funded by the Wyoming INBRE program, and led by Dr. Hayley C. Lanier (now at the University of Oklahoma) and Dr. Scott Seville (project PI, University of Wyoming). The scope of this periodical study covered the population dynamics and succession of plants and small mammals following large scale burns such as the 1988 Huckleberry Mt. Fire in Yellowstone National Park. Along with the succession research (2017), I conducted an experiment to test the effects of crypsis on predation rates in these post-burn environments among deer mice and southern red-backed voles. My current prospective PhD work centers around two main and related themes of bumble bee thermal physiology. The first involves using respirometry and other thermal tolerance methods to characterize the winter dormancy (diapause) of bumble bee queens, and the second pertains to understanding where heterothermic insects (bumble bees) fall on the “thermy-continuum” in relation to various types of dormancy exhibited across taxa.

CRAIG GARZELLA, DOCTORAL STUDENT IN program in ecology and evolution

I received my MS in Analytics and Modeling and my BS in Biology from Valparasio University in 2019 and worked as a data scientist investigating invasive species for the USGS and the NPS before starting my Ph.D. at the University of Wyoming in Program in Ecology and Evolution. My master’s studies focused on the identification of RNA-binding proteins using machine learning techniques, while my bachelors work focused on the investigation of non-random mating in Arabidopsis species.  At UWYO my research is focused on applying data science techniques, statistics, and mathematical modeling to investigate the survivorship of overwintering bumblebees. My interests include applying agent-based models to investigate the fitness of ectotherms in microclimatic mosaics and broadly applying computational approaches to address question in ecophysiology.    @GarzellaCraig


I am currently working towards my BS in Biology and plan to graduate from the University of Wyoming in the Fall of 2021. I transferred to the University of Wyoming from UW Casper in Fall of 2020. For the time I have been attending the University of Wyoming I have been an INBRE Transition student and also received the INBRE Summer Internship to conduct research in the Dillon lab for Summer 2021 . My research focuses on bumble bee chill coma and the cellular mechanisms involved in chill coma. My broad interests lay in entomology and ecology. Once I graduate from the University of Wyoming, I plan to pursue a graduate degree.


In 2012, I received a BS in Environmental Biology and a BA in Spanish from Fort Lewis College in Durango, CO  with a thesis focused on the effects of Sudden Aspen Decline on understory microclimates and plant biomass. The following years I worked at a human tissue bank cleaning and processing donor grafts in an aseptic environment and ultimately coordinating grafts for transplant. As a second-year graduate student, I am focused on the cold tolerance of bumble bees, specifically looking at how diet and temperature influence bumble bee thermal physiology and cellular composition through lab and field studies. Broadly, I would like to link climate and altitude with floral phenology to identify the indirect cascading effects of environmental shifts on bumble bees.


 I am currently working towards my BS in Physiology with a Honors Minor, and I plan to graduate in the fall of 2022. My research focuses on water content in bumble bees. I am specifically looking at how high altitudes impact the water content of bumble bees as well as how various water contents affect the bee’s ability to withstand hot temperatures. Overall, I am interested in the effects of high altitudes.



Broadly, I study queen bumble bee overwintering physiology. I am currently exploring how where a queen bumble bee overwinters influences her survival and energy usage while overwintering, and/or her fitness post-winter. Through a combination of field work, lab work, and empirical modeling approaches, I aim to predict if the changing climate may impact bumble bee abundance and spatial distribution now and in the future.

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Travis’ postdoctoral research in the Dillon Lab focused on the thermal physiology of bumble and solitary bees.  He accepted a postdoctoral position at the USDA in Manhattan, Kansas.


Ethan was both a Wyoming Research Scholar and an recipient of a Wyoming NASA Space Grant fellowship. He coordinated between the Dillon lab and the Rule lab to use GC-FID to characterize fatty acid profiles for bumble bees, evaluated behavioral indicators of bumble bee queen rearing success, and characterized seasonal variation in sub-nivean insect communities and their thermal performance. He is now a PhD student in Michael Smith’s lab at Auburn.

Sarah Wannemuehler

SARAH WANNEMUEHLER, BS wildlife and fisheries biology and management, 2021

As a Wyoming Research Scholar and Wyoming NASA Space Grant fellow, Sarah studied how altitude and water affect dissolved oxygen in streams, rivers, and lakes and how, in turn, temperature and DO structure size distributions of aquatic invertebrates.

Roman Winter

ROMAN WINTER, BS Zoology, 2021

ANNA CRESSMAN, BS Wildlife and fisheries biology and management, 2019

Zach Parsons, BS Zoology, 2019

Delina Dority, MS Zoology and Physiology, 2019

Christy Bell, MS Zoology and Physiology, 2019

Kennan Oyen, PhD Program in Ecology, 2018

Susma Giri, PhD Program in Ecology, 2016


Annie Krueger, BS Physiology, 2016


Kimberly Sheldon, NSF Postdoctoral Fellow, 2014-2016

Sarah DePaolo, MS Zoology and Physiology, 2015

Jessica Vogt, MS Zoology and Physiology, 2014

Olivia H.A. Nater, MS Zoology and Physiology, 2014

Olivia completed her MS on the impacts of recent climate change on native bee and plant populations. She is now working for the IUCN in Geneva, Switzerland.

Jonathan Rader, MS Zoology and Physiology, 2014

Jonathan completed his MS looking at morphological diversification and isotopic niches of Cinclodes ovenbirds. He is now a PhD student in Ty Hedrick’s lab at UNC.

Mary Centrella, BS Zoology, 2013

Mary is working with Bryan Danforth and Katja Poveda.

Brandon Ray Buckio, BS Zoology, 2012

John Bruno (aka “Brawno”), BS Physiology, 2012

Sadie L. Todd, CLM Intern