Systematic Status of Kangaroo Mice, Genus Microdipodops: Morphometric, Chromosomal, and Protein Analyses

Publisher Website
Google Scholar
Abstract
The systematic status of Microdipodops megacephalus and M. pallidus is investigated at the genic, karyotypic, and morphologic levels at a purported hybrid zone. Instances of hybridization are shown to be either nonexistent or present at extremely low levels (≼0.6%), and full specific status of the two taxa is affirmed. Amounts of genic variability and polymorphism are approximately equal for the species (H = 0.064) and fall well within the range observed for other vertebrate species. Estimates of the timing of the speciation event, based upon allozymic data, range from 1.2 to 6 million years before present. Possible means of ecological separation of the two sibling species in sympatry are suggested.