Frost, StephenEller, Andrea2020-02-272020-02-272020-02-27https://hdl.handle.net/1794/25290Generalist and specialist species can be broadly distinguished by their ecological tendencies to utilize many available resources, or a selected few. Those organisms with more ecological versatility may have an advantage in the face of environmental fluctuation or rapid ecological change (Turley and Frost 2018; Antón, Potts, and Aiello 2014; Kuzawa and Bragg 2012; Davidson, Jennions, and Nicotra 2011; Ash and Gallop 2007). Developmental plasticity may provide a mechanism for fluctuating environmental pressures to impart increased phenotypic variation to an adult population (Antón et al 2016; West-Eberhard 2003). The aim of this dissertation is to evaluate whether more ecologically versatile species will exhibit greater phenotypic variation. Eighty-one skeletal traits were analyzed across cranial, dental, and postcranial anatomic regions, using a total sample of 4084 individuals in six selected catarrhine primate species. To do this, I reported measures of variation for each skeletal trait (sample variation, standard deviation, and the coefficient of variation), assessed variation using principal components analyses, and ultimately tested for significant differences between taxa using general linearized models. The main hypothesis of this dissertation, that ecological versatility positively correlates with phenotypic variation, was not supported among the majority of skeletal features examined. Where significant results did occur, such as cranial differences between male Pan troglodytes and Homo sapiens (Chapter One), where Homo sapiens displayed more variation, or long bone length differences in Papio and Theropithecus (Chapter Two), where P. hamadryas displayed more variation, the patterns were subtle and sometimes contradictory. Chapter Three results indicate that sample sizes required for accurately detecting patterns of phenotypic variation range from 30-52 individuals for molar areas, 10-16 individuals for femoral lengths. These sample sizes are substantially larger than those offered by Antón, Potts, and Aiello (2014), indicating that the ability to detect increased intra-taxon variation within more ecologically versatile species may be beyond currently available hominin fossil sample sizes. Future investigations should focus on traits which are developmentally plastic, such as long bone lengths, as informative for understanding the adaptive relationship between ecological versatility and phenotypic variation. A complete list of specimens used in this study is available in Supplemental Files.en-USAll Rights Reserved.Electronic Thesis or Dissertation