While TCU’s recent successes on the football field may have introduced horned frogs to the world, the real Texas horned lizard (Phrynosoma cornutum)
has been declining through much of its range, including a virtual
disappearance from Eastern and Central Texas. Dr. Williams and Dr. Hale
have developed a set of genetic markers to study the population
structure and movement patterns of horned lizards in Texas to determine
if present-day populations have experienced significant genetic
declines. With the help of many volunteers from Texas Parks and
Wildlife, the Horned Lizard Conservation Society, and TCU samples were
obtained from over 600 lizards.  The genetic data indicate that Texas
horned lizards can be grouped into several large clusters across the
state. With the exception of two areas which showed evidence of genetic
declines, genetic diversity was generally high and differentiation was
low across Texas, suggesting that most populations are healthy.  Genetic
data also suggest that dispersal in Texas horned lizards is sex-biased,
with males dispersing longer distances than females.  In this month’s
installment of brains and brews, Dr. Williams and Dr. Hale will discuss
the conservation implications of the data, including what they might
mean for the eventual reintroduction of horned lizards into areas from
which they have disappeared.

About Dr. Williams and Dr. Hale

Dean
Williams and Amanda Hale are assistant professors of biology at Texas
Christian University.  Dr. Williams received his Ph.D. in ecology from
Purdue University, W. Lafayette, Indiana. His areas of expertise include
ecology and evolution, population genetics, and conservation biology. 
The current focus of his lab is on the conservation genetics of
endangered and threatened species as well as invasive species. Dr. Hale
received her Ph.D. in biology from the University of Miami, Coral
Gables, Florida.  Her areas of expertise include ecology and evolution,
population genetics, and conservation biology.  The current focus of her
lab is investigating the impacts of wind energy development on birds
and bats. The two professors, along with their two young sons, moved to
Fort Worth nearly four years ago to join the faculty at TCU.