Biochemical Polymorphism and Systematics in the Genus Peromyscus. III. Variation in the Florida Deer Mouse (Peromyscus floridanus), a Pleistocene Relict

Electrophoretically demonstrable variation was analyzed in proteins encoded by 41 structural gene loci in 71 individuals of the Florida deer mouse (Peromyscus floridanus) representing four sample areas. Of the 39 loci that were scorable in all individuals, 15 (38 per cent) were polymorphic in one or more populations. The average number of alleles detected per polymorphic locus was 2.01 (range 2 to 3). Average individual heterozygosity was 5.3 per cent. Populations of P. floridanus are less variable genetically than sympatric populations of the old-field mouse (P. polionotus), but similar in this regard to populations of the latter species from t0he Florida Panhandle and from South Carolina and Georgia. Coefficients of genetic similarity for paired geographical populations of P. floridanusranged from 0.96 to 0.98, reflecting little geographical variation in allele frequencies. A comparison of P. floridanuswith P. polionotusfrom five regions yielded coefficients of genetic similarity varying from 0.31 to 0.33.