Date of Graduation


Document Type


Degree Name

Master of Arts in Anthropology (MA)

Degree Level





Claire Terhune

Committee Member

Lucas Delezene

Second Committee Member

Jerome Rose


Craniofacial Morphology, Fluctuating Asymmetry, Primate


Fluctuating asymmetry (FA) – random deviations from bilateral symmetry in an organism’s paired features – is a good candidate for investigating developmental stability. This easily accessible measurement can be used to understand the relationship between stress and development across organisms, and growth rate plays a vital role in developmental processes. Few studies have investigated craniofacial FA in non-human primates, and those that have suggest that levels of FA are higher in slower growing species. This study examines craniofacial FA in two primate species (Pan troglodytes troglodytes and Gorilla gorilla gorilla; n=81) to elucidate the effect of growth rate on FA in non-human apes. Results suggest that Gorilla exhibits higher levels of FA than Pan, and male gorillas show higher levels of FA than female gorillas. These results indicate that FA is correlated with growth rate, meaning that species with slower growth (i.e., Pan) may have greater developmental stability. Further analyses will help tease apart the factors contributing to differential response to environmental and genetic stress to contribute to a broader understanding of primate canalization and developmental stability.