Molecular characterization of a hybrid zone in mule deer

Mule deer (Odocoileus hemionus) is comprised of two evolutionarily divergent lineages, mule deer and black-tailed deer. These lineages are morphologically, ecologically, and genetically distinct, yet hybridize readily within a zone of contact along the Cascade Mountain range (Washington/Oregon). Previous investigations have focused primarily on the western side of the contact zone. The objective of this research was to characterize patterns of hybridization within the relatively unexplored eastern side of the contact zone, and combine our data with previous work to create a clearer picture of hybridization across the region. We collected tissue samples from approximately 150 deer on the eastern side of the contact zone, extracted DNA, and used PCR to amplify 11 microsatellite loci for each individual. Genotypes revealed deer from both lineages and many hybrids across the eastern contact zone. Placed in a larger context, these data indicate widespread hybridization across the entire contact zone. These data will help us create a more accurate view of the hybrid zone, with important implications at a broad scale to gain more information about stable hybrid zones in general, and on a smaller scale to learn about the introduction, integration and stability of the species in its natural environments