Date of Award
Doctor of Philosophy (PhD)
This dissertation is an explication of baboon craniofacial variation and its genetic basis. Intraspecific variation is the result of input from and complex interactions among genetic information, functional demands, and developmental processes. The relative effect of each of these on craniofacial variation, as well as the degree of inter-trait covariance, determines whether traits can respond to selection and what that response might look like. Using a sample of pedigreed baboons, I quantify craniofacial variation to address specific questions regarding the distribution and magnitude of phenotypic, genetic, and environmental variation patterns. In addition, I identify regions of the genome containing genetic variants contributing to the production of craniofacial variation. Results demonstrate that the genotype-phenotype map for craniofacial variation in this sample is characterized by patterns of inter-trait correlation that are structured by both functional and developmental relationships. Much of the additive genetic variation is likely pleiotropic and contributes to craniofacial variation regionally, rather than globally. The degree to which regions are affected by this genetic variation lacks patterning, indicating that no one particular region is any more evolvable than others. Finally, after accounting for differences in cranial size among individuals, both the magnitude of genetic correlations and the amount of additive genetic variation decreases, which suggests selection for body size played a major role in craniofacial evolution in baboons.
Chair and Committee
James M. Cheverud, Allan Larson, Jane E. Phillips-Conroy, Richard J. Smith,
Joganic, Jessica Lynn, "A Quantitative Genetic Analysis of Craniofacial Variation in Baboons" (2016). Arts & Sciences Electronic Theses and Dissertations. 802.