Dean Leavitt

From Dean Leavitt, 2009 recipient of the Howie Wier Memorial Conservation Grant:

"Some of my earliest childhood memories involve rescuing small toads from the lawnmower and box turtles from the highways in Oklahoma. When I moved out West at the age of four, I quickly became fascinated by the lizards I saw while camping with my family. This interest hung around as I grew older and helped lead me to study biology in college. My senior year I had the opportunity to help sequence lizard DNA in a genetics lab, and it wasn’t long before I was doing my own research studying genetic relationships among different lizard populations. As a master’s student, I had the opportunity to study the Desert Night Lizard – a small, secretive lizard found throughout much of the Desert Southwest. My work and others’ on these lizards have shown that while populations of night lizards appear quite similar to us visually, genetic data indicate the presence of multiple, ancient species.

For my dissertation work, I have continued studying genetic questions regarding lizards in the Desert Southwest. We are still not sure exactly how many species of night lizard live in southern California, and the increased availability of new genetic tools provide an improved ability to determine this question. Due primarily to a complex geological history, the Anza-Borrego region in particular appears to be a night lizard “hotspot”. For my research, I am testing whether populations of the Desert Night Lizard in Anza-Borrego represent one, two or three species. Also, if more than a single species are found, what are their distributions? And do the different species hybridize where their distributions come into contact? To answer these questions, I catch individual lizards from throughout the region. After removing the tip of the tail and preserving it in alcohol, I release the lizards relatively unharmed. This small tissue sample will provide an ample amount of DNA for genetic work in the laboratory.

 Night Lizard, photo by Marshal Hedin

This research is important because it helps us understand the processes that lead to the formation of new species and the patterns of biodiversity we observe in southern California. Much of the land in southern California is under intense human pressure, and the discovery of genetically distinct populations coupled with an understanding of how this diversity is distributed allow us to help prevent the loss of that unique biological heritage."