Meeting Abstract

55.2  Thursday, Jan. 6  The population genetic structure of ground snakes (Sonora semiannulata) COX, Christian L*; DAVIS, Alison R; The University of Texas, Arlington; The University of California, Berkeley clcox@uta.edu

Population size, gene flow, and genetic diversity affect the persistence of populations through time and space. Organisms with small body size and low vagility may be especially sensitive to perturbations in population connectivity, as populations can easily become geographically isolated and lose genetic diversity in small populations. One such vulnerable group is the phylogenetically diverse but ecologically similar semifossorial snakes of the Great Plains. We used one of these snake species (Sonora semiannulata) to characterize population genetic structure and assess genetic diversity and population connectivity across Texas, Oklahoma, Colorado, and Kansas. We analyzed 160 amplified fragment length polymorphisms (AFLPs) to estimate population structure for 12 populations of ground snakes (a total of 228 snakes) across the region. Generally, we found that genetic diversity was high and population structuring was low, even across such a large spatial scale. This pattern may be explained by high rates of gene flow, recent range expansion, or a combination of both processes. If other small fossorial species in the Great Plains show a similar lack of genetic structure, it may indicate that these populations can maintain connectivity despite habitat fragmentation and modification.