Lab Members

Doctoral Students

Stephen Rice

I received my B.A. in Biology with concentrations in molecular/cellular and ecology/evolution from UNC Asheville in 2003 and my M.S. in Biology from Old Dominion University in 2011.  I am broadly interested in evolutionary ecology, especially understanding the severity (and possible)  effects of anthropogenic changes on taxa at the current era, and the potential consequences of those changes on the potential evolutionary path of organisms.  My current project is working on a molecular species ID of Peromyscus species for the western U.S. as well as landscape genetics.  My Master's research was evaluating transience in open-habitat rodent populations as it relates to current dogma's of deme and sex/age biased dispersal and philopatry.  Additional areas of interest range from anatomy and physiology to the pharmacological activity of venom components. Email:


Hannes Schraft

I received a BSc in Biology at the University of Puerto Rico where I was involved in research on the performance of trilled bird songs. Since then my interests have shifted slightly to the behavior and sensory ecology of reptiles. My dissertation will investigate the resolution and sensitivity of rattlesnake pit organs, and the extent to which rattlesnakes can use leaked thermal information from their prey to make foraging decisions. Specifically, I want to determine whether rattlesnakes make decisions regarding striking prey or ambush site selection based on their prey’s thermal signatures.   Email:

Whitford, Malachi

Malachi Whitford

Broadly, I am interested in how the behaviors of both predator and prey influence the outcome of predatory interactions. My current research uses in situ  facilitated interactions between rattlesnakes and kangaroo rats, coupled with high-speed videography techniques, to discern whether behaviors expressed during an interaction and/or the morphology of the participants predict the eventual outcome of the interaction.Email:

krat pic

Grace Freymiller

I am  interested in predator-prey systems, and I am more specifically interested in the interactions between herpetofauna and their prey. I am working on several research projects that focus on various aspects of behavior, including thermoregulatory behavior of sidewinders (Crotalus cerastes) as well as an interspecific comparison of evasive behaviors in kangaroo rats (Dipodomys spp.) during simulated snake strikes. Email:

Masters Students

Kelly Robinson

I received my B.S. in Environmental Science with a focus in Biology from the University of Iowa. I have general interests in behavior, predator-prey interactions and conservation of herpetofauna. My current research is being conducted on the variation in venom resistance among California ground squirrels (Otospermophilus beecheyi) and woodrats (Neotoma spp.). I will be exploring the variation and potential constraints of their resistance levels to two species of local rattlesnakes; red diamond rattlesnake (Crotalus ruber) and southern Pacific rattlesnake (C. helleri).

Roman Nava

My main interests are animal behavior and conservation, and here I am interested in how species change their behaviors as a result of natural and anthropogenic fragmentation, and seeing if there is any convergence (or difference!) in how species respond to fragmentation across fragments created by urbanization or islandization . I look at morphological changes coupled with personality assays, combining two sets of data to draw insights from. My current project tests these ideas on a handful of squamates at a few sites around San Diego County and Coronado Sur of Baja California, Mexico. As urbanization rapidly increases, it is important to know if species are responding to fragmentation caused by humans in a similar way to fragmentation caused by natural forces over thousands of years. 

Jordyn Mulder

I received my B.S. in Wildlife Biology with an emphasis in management and conservation at Humboldt State University in 2013. Since then, I have pursued my passion for herpetofauna.  My main topics of interest are animal behavior, conservation, and human and wildlife interaction. My graduate research will take place in American Samoa studying local lizard populations and how they, and the flora communities they reside in, have changed over the past 40+ years. Specifically, looking at how the different taxa utilize their environments.  Email:

Craig Fischer


I have long been interested in myriad aspects of ecology, using my bachelor's in Biological Sciences from Marquette University and bio tech positions in public lands to ask pointed questions about effects of climate change, habitat alteration, and recreation on ecology of public lands. Four years working in the Colorado Desert have given me ample opportunity to develop questions regarding the ecology of this remarkable region. My research focuses on how natural and anthropogenic landscape factors may affect genetic diversity of flat-tailed horned lizards (Phrynosoma mcallii) within an off-road focused recreation environment. Email:

Nathaniel Redetzke


Clark Lab Alumni

Shannon Hoss, PhD 2013, Maternal attendance of young in cottonmouths (Agkistrodon piscivorus): Adaptive value and hormonal mechanisms.

Bree Putman, PhD 2015, The function and ontogeny of antipredator responses: the influence of snakes on ground squirrel behavior and physiology 

Matthew Barbour, MS 2012, Investigating the function of California ground squirrel (Otospermophilus beecheyi) displays towards northern Pacific rattlesnakes (Crotalus oreganus) 

Frank Santana, MS 2013, Mountain yellow legged frog (Rana muscosa) conservation: multiple approaches

Laura Kabes, MS 2014, The use of chemical cues by granite night lizards (Xantusia henshawi) to evaluate potential predation risk

Tara Luckau, MS 2015, Comparative conservation genetics of two sympatric lizard species across multiple landscapes in San Diego County

JP Montagne, MS 2015, The effect of personality on movement and survival following translocation of California ground squirrels (Otospermophilus beecheyi)

Kelly Lion, MS 2016, A comparative study of genetic patterns in two closely related and sympatric Peromyscus species

Last Updated:  August 2017