The climatic and environmental fluctuations of the Quaternary played an integral role in geographic distribution and genetic structure within many organisms today. Understanding how these historical biogeographic events may have partitioned genetic variation throughout the landscape is critical to forecasting the implications of modern climate change and how animals will respond to projected climate shifts. Through geographic and taxonomically comprehensive sampling, we used multi-locus and species delimitation analyses along with niche modeling methods to investigate the evolutionary and biogeographic history of the meadow vole, Microtus pennsylvanicus. The findings of this study highlight the vulnerability and importance that special consideration and conservational strategies be taken to preserve peripheral populations that harbor unique characteristics. The dynamic evolutionary and geographic history of the meadow vole furthers our understanding of the important role Quaternary climatic oscillations played in the diversification and geographic distribution of organisms today
