Michael Packer, Utah Valley University
Life Sciences
Dipsosaurus dorsalis is a desert dwelling iguana species geographically distributed throughout the south-western United States, northern Mexico, and the Baja Peninsula. Throughout the Baja Peninsula, multiple species of herpetofauna exhibit a distinct north-south division, both morphologically and genetically, with no presence of any physical barriers. The goal of this study was to examine how the genetic structure of D. dorsalis has been influenced by past geological events, and whether this species exhibits a similar north-south division on the Baja peninsula. Additionally, this study aimed to see if the current taxonomy of Dipsosaurus is reflective of the evolutionary relationships across its entire geographic range. 100 tissue samples of D. dorsalis were collected across the species geographic range. DNA extraction from collected tissue samples and sequencing of nuclear loci MLH3 (~900bp), NT3 (489bp), as well as mitochondrial loci ND4 (~900bp) were performed to examine the distribution of genetic variation in D. dorsalis. The collected data was then used to construct phylogenetic trees for each locus, comparing individuals of Dipsosaurus to the geologic history of its geographic distribution. Although shallow, a maximum likelihood tree of the ND4 mitochondrial gene shows the phylogeographic separation of three distinct clades. The results do not support the designation of Dipsosaurus catalinensis as currently defined.