Determination of the Functional Morphology and Locomotor Mode of an Early Eocene Protocetid Whale from Georgia

• Main Author: Aleshire, David Patrick
• Format: Text
• Language: unknown
• Published: Digital Commons@Georgia Southern 1994
• Subjects: ETD; Skeleton; Protocetid whale; Georgia; Morphology; Comparative dissection; Comparative anantomy; Biochemistry; Biophysics; and Structural Biology; Biology; Odobenus rosmarus; Phoca vitulina
• Online Access: https://digitalcommons.georgiasouthern.edu/etd_legacy/575; https://digitalcommons.georgiasouthern.edu/context/etd_legacy/article/1414/viewcontent/53_02.pdf

An associated skeleton of a protocetid whale from Georgia includes 22 vertebrae (3 cervicals, 7 thoracics, 8 lumbars, 4 sacrals, and 1 caudal), 14 ribs, and a complete pelvic girdle. Analysis of the morphology of the hindlimb and pelvic musculature by comparative dissection and anatomy of Recent terrestrial, semi-aquatic, and manne mammals (Felis earns, Lutra canadensis, Enhydra lutris, Zalophus californianus, Phoca vitulina, Odobenus rosmarus, and Tursiops truncatus) suggest that the protocetid had less development of its pelvic muscles and hindlimb than terrestrial mammals. This also suggests that the protocetid was not capable of terrestrial locomotion. The pelvic musculature demonstrates the most similarities to Lutra canadensis. Analysis of the vertebrae and its muscles by comparative dissecdon and anatomy suggests that the protocetid was progressing toward vertebral-column propelled aquatic locomotion. Comparative analysis of the neural canal cross-sectional area indicates that the protocetid possessed evident innervation of its hindlimbs and trunk muscles suggesung that they were the main means of aquatic locomotion for the protocetid.