A zoogeographic analysis of variation in Recent Geomys pinetis (Geomyidae) in Florida

Abstract

Cranial characters were used to assess phenetic relationships of Geomys pinetis populations in Florida. The observed pattern of geographic variation is examined in light of rivers and patchy distribution of suitable habitats that influence dispersal of pocket gophers and the effects of sealevel changes on isolation of populations. Phenetic breaks in the pattern of geographic variation correspond to the Apalachicola and, to a lesser extent, the Suwannee rivers. Several features of these river corridors explain their relative effectiveness as barriers: (1) potential for gene flow around river headwaters, (2) effective width of the river corridors, and (3) various streamflow parameters. The barrier effects of the Apalachicola and Suwannee rivers on other vertebrate and invertebrate taxa are discussed.