COMPARATIVE HIND-LIMB MORPHOLOGY IN GEOMYINE AND THOMOMYINE POCKET GOPHERS

Dissections of hind limb muscles in pocket gophers (Geomys, Thomomys, Cratogeomys, Orthogeomys) revealed 14 myological differences that supported both the monophyly of the Geomyidae with respect to the Heteromyidae and the separation of this family into two tribes. However, observed differences did not reflect reported functional similarities of the hind limbs in these taxa and they contrasted in nature with the types of myological variation observed in the forelimbs of these mammals. These results demonstrate the usefulness of myological characters in phylogenetic analyses and highlight the need for quantitative, functional studies that would clarify the action of hind limb muscles in these rodents.