Molecular and morphological variation in Neotoma cinerea

Neotoma cinerea, the bushy-tailed woodrat, is a wide-ranging species displaying broad phenotypic variation cataloged by researchers through the last 200 years. However, all major taxonomic revisions and assessments of morphological patterns pre-date modern molecular and statistical techniques, which can help clarify evolutionary histories and relationships within taxa. The aim of this study is to assess broad-scale molecular (cytochrome b) and craniodental morphological variation in N. cinerea, and to infer biogeographic history from these data coupled with dated paleomidden records. Two major phylogenetic clades were identified, showing an average uncorrected sequence divergence of 6.5%. Morphology seems to be more strongly correlated with potential environmental variables than with phylogeny, supporting assertions that N. cinerea is sensitive to climate and evolves morphologically in response to it. Inferred biogeographic histories of the major clades suggest allopatry and independent evolution until relatively recently, and both molecular and morphological evidence suggest interbreeding between the major clades in regions of secondary contact