Masters Theses
Date of Award
6-1976
Degree Type
Thesis
Degree Name
Master of Arts
Major
Anthropology
Major Professor
Fred H. Smith
Committee Members
William M. Bass, Avery M. Henderson
Abstract
Controversy concerning Neandertal man’s place in anatomically modern man’s ancestry continues today, 120 years after the discovery of the first Neandertal at Dusseldorf. The major emphasis of this controversy concerns the cranium. In the postcranial material, however, there are two areas which exhibit morphological differences from modern man, all other postcranial features being within the ranges of variation of modern man. These two different postcranial features are: the morphology of the superior pubic ramus of the innominate and the morphology of the axillary border of the scapula. This thesis is concerned with the latter feature.
While the axillary borders of modern men commonly exhibit a ventral groove, two-thirds of the known Neandertal scapulae where the axillary border is preserved exhibit a double sulcus, or bisulcate pattern. This latter type was first noted on the axillary border of the Upper Paleolithic specimen from Chancelade. This Chancelade-type morphology occurs much more frequently in Upper Paleolithic hominids than in modern populations. The ventral or modern type is seen in one Upper Paleolithic specimen and has never been seen with certainty among Neandertals.
The purpose of this thesis is to test hypotheses concerning the changes on the axillary borders of scapulae between Neandertal and modern man. Comparative material used in this study was drawn from skeletal material of Arikara American Indians which are housed in the Osteological Laboratory of the Department of Anthropology at the University of Tennessee, Knoxville.
Correlations between various scapular axillary border morphologies with respect to age, sex and side were sought. Relationships between the various axillary border morphologies and the angle of the glenoid fossa, as well as the index of the glenoid fossa, were tested, but consistent correlations were not found. Positive correlations were found between the robusticity of the infraglenoid tubercles and axillary border morphologies, as well as between border morphologies, and associated humeral head angles.
The results of this investigation suggest that the morphology of the axillary border of the scapula is a function of use. The incidence of the Chancelade type is generally greater with advancing age and on the right side. This indicates ontogenetic causes for the varying morphologies. Correlations between varying morphologies and humeral head indices and head/shaft angles indicate that varying scapula-humeral relationships influence the morphology of the axillary border of the scapula. In Neandertals, the barrel-shaped thorax appears to have resulted in scapulohumeral musculoskeletal relationships in the shoulder area which could have caused greater stress to be exerted on the teres minor muscle, thus creating the dorsal groove on the axillary border of the scapula.
It is suggested that the differences in morphological patterns on the axillary border of the scapula found between Neandertal and modern man can be functionally explained by (1) differences in the scapulohumeral relationship, and (2) greater biomechanical stress in the shoulder area of Neandertals than that of modern man due to the difference in cultural adaptations.
Recommended Citation
Dittner, Carol B., "The Morphology of the Axillary Border of the Scapula With Special Reference to the Neandertal Problem. " Master's Thesis, University of Tennessee, 1976.
https://trace.tennessee.edu/utk_gradthes/2904