On the Origin and Spread of an Adaptive Allele in Deer Mice

Abstract

Adapting Coat Color Simple phenotypic changes can often be the target of selection—for example, variations in coat color that provide protection against detection by predators. Linnen et al. (p. 1095 ) explore the underlying molecular mechanisms behind the production of pale deer mice living on the light-colored Nebraska Sand Hills. The mice that live on the sand are significantly lighter in color than conspecifics living nearby on darker soils. This lighter color was found to be due to de novo changes at the Agouti coat color locus. Thus, rapid adaptive change does not always rely on preexisting genetic variation.