A comparative study of the osteology and myology of the thoracic limb of the pocket gopher and kangaroo rat
Abstract
The purpose of this study was to determine the morphological differences in the osteology and musculature of the thoracic limb of the pocket gopher and kangaroo rat. This was accomplished by first, collection of specimens, second, the preservation and preparation of bones and muscles tor study and illustration, third, sketching and photographing the sketches, fourth, noting and recording origins and insertions as well as any differences in the modification of anatomy with relation to habitat requirements. These two closely related families, Geomyide and Heteromyidae, show great morphological differences. Comparative volumetric measurements show that the forelimb of the pocket gopher is approximately twice the size of the forelimb of the kangaroo rat. Differences in the myology were found in relative length, thickness, shape, overall size, and in origin and insertion. Variations were also found in the osteology of the two forms. These differences were general outline, locations of the tuberosities for muscle attachment and in the length and placement of the various bone processes.