Date of Graduation


Document Type


Degree Name

Master of Arts in Anthropology (MA)

Degree Level





Joseph Plavcan

Committee Member

Peter Ungar

Second Committee Member

Justin Nolan


Comparative Anatomy, Elbow, Hominid, Joint, Primatology, Ulna


Large body size requires limb joints capable of supporting said weight, and a species exhibiting sexual size dimorphism may necessitate joint size differences between the sexes of the species. If habitual behavior differs with body size, one may expect to see significant variation in joint morphology between species and the sexes within species. The following analysis tests two hypotheses: (1) that significant differences in joint size between males and females correlate with the magnitude of sexual dimorphism and (2) that there is significant interspecific variance in joint shape between males and females of the same species. The first hypothesis is tested by taking principal component scores from the first two components of a Principal Component Analysis (PCA) with full tangent space and Procrustes form space projection and subjecting them to an Analysis of Variance (ANOVA) to see if a significant amount of variance exists between sexes for each species observed. The second hypothesis is tested in the same way, the only difference being that the PCA utilizes solely a full tangent space projection in order to nullify size differences in variance. The results of the analysis show that the magnitude of sexual dimorphism correlates with differences in joint size. However, there is no significant interspecific variation in shape between males and females in the same species. The analysis did not have a consistent sample size for all sexes or species and the sample sizes were all relatively small. As such, an analysis with larger samples and greater consistency will be needed to confirm the inferred conclusions.