Taxonomic Status of Peromyscus gossypinus anastasae (Anastasia Island Cotton Mouse)

Abstract

Four subspecies of cotton mice (Peromyscus gossypinus) were examined to assess the taxonomic validity and affinities of the mice on Cumberland Island, Georgia, and Anastasia Island, Florida, both of which are presently referred to P. g. anastasae. Genetic analysis of 44 loci in 379 mice from 14 populations (six island, eight mainland) and morphometric analysis of 27 characters on 683 mice from 20 populations were performed. Polymorphic loci and heterozygosity per population averaged 40 and 10%, respectively, and there was no reduction of genetic variability on islands. Insular mice tended to be smaller than mainland mice. Every population was genetically or morphologically different from all other populations for at least one character in pairwise comparisons. However, when all populations were examined simultaneously, the pairwise differences were not significant. While each population was statistically distinct, none was unusually distinct, and neither the Cumberland Island nor Anastasia Island populations of P. g. anastasae warrant recognition as separate subspecies.