Meeting Abstract
House mice, Mus musculus domesticus, have recently expanded their range across the Americas, encompassing diverse habitats ranging from tropical to arctic climates. The challenges of adapting to different temperature, precipitation, and seasonal regimes make house mice an ideal system for understanding the genomic and physiological bases of rapid environmental adaptation. Using brother-sister mating, we are creating new wild-derived strains mice from five different populations in North and South America. Using these new strains, we found morphological differences among populations consistent with both Bergmann’s rule and Allen’s rule: mice from New York are larger and have shorter ears and tails than mice from Brazil. Moreover, mice from New York are larger, build bigger nests, and are more active than mice from Brazil. Lastly, house mice from New York and Canada have larger average litter sizes than mice from Brazil. These differences persist in the lab over multiple generations indicating that they have a genetic basis. We conclude that despite recent introduction to the Americas, house mice have undergone rapid adaptation to various environments.
