Temperature Selection in Peromyscus and Laboratory Mice, Mus Musculus

Three kinds of Peromyscus and the laboratory mouse, M. musculus, maintained under constant temperature conditions, were tested in a horizontal temperature gradient with floor temperatures ranging from about 5 to 45° C. White-footed mice (P. leucopus noveboracensis) and laboratory mice had the highest selected temperatures and the lowest variability in the selection response (32.4°, sd = 1.3°; 31.8°, sd = 2.5°), while forest deer-mice (P. maniculatus gracilis) and prairie deer-mice (P. maniculatus bairdi) had the lowest mean selected temperatures and the greatest variability in response (29.1°, sd = 4.7°; 25.8°, sd = 5.2°). The ecological and taxonomic implications of these differences are discussed.