Phylogeography combines the study of ancestor-descendant relationships and the geographic distribution of an organism to trace its evolutionary history. This study focuses on the molecular evolution of Microdipodops pallidus , a species of heteromyid rodent found in the lower elevations of the Great Basin Desert.The distribution of M. pallidus is dissected into several disjunct geographic units (or localities), each with its own separate population of kangaroo mice. Individuals were collected from 17 localities within the M. pallidus distribution and DNA was extracted from the tissue of each animal. To examine the molecular evolution of the mice collected, a 650 bp fragment of 16s ribosomal DNA from the mitochondrial genome was amplified using polymerase chain reaction (PCR). Upon purification of the PCR products, the 16s region of each individual sampled was sequenced and edited.Thus far we managed to construct a preliminary parsimony tree that represents plausible relationships between kangaroo mice sampled from different localities. Our current results supports previous research of chromosomal analysis on M. pallidus which suggests an western-eastern split in the center of their geographic distribution. Additionally our analysis of the individuals sequenced thus far shows little molecular divergence between the western localities despite geographic barriers and distances between each population.