Species limits and phylogenetic relationships among populations of Peromyscus furvus

We examined electrophoretic variation at 33 presumptive protein-coding loci for seven populations of Peromyscus furvus to determine population structure and test hypotheses of species boundaries. Protein electrophoresis revealed few fixed differences among populations and no diagnostic fixed alleles. Phenetic analysis of biochemical data support the hypothesis that P. furvus is a single phylogenetic entity. Populations from Jalapa, Veracruz, Mexico, and Puerto de la Soledad, Oaxaca, Mexico, were the most divergent. Polymorphic characters were subjected to parsimony analyses using presence-absence and frequency coding. Parsimony analyses showed that populations formerly recognized as P. angustirostris, P. furvus, and P. latirostris were not monophyletic groups within P. furvus (sensu late). However, a high degree of population subdivision was detected. Working within the framework of the phylogenetic species concept, we concluded that populations of P. furvus represent one monophyletic species.