Testing Adaptive Hypotheses of Plio-Pleistocene Hominin Craniofacial Evolution

This project explores adaptive hypotheses for craniofacial evolution in Plio-Pleistocene hominins, with a particular emphasis on the functional, developmental and evolutionary factors that shaped skull morphology from roughly two million to perhaps 60,000 years ago. Combining virtual reconstruction techniques, quantitative analyses of cranial shape variation, and approaches drawn from quantitative genetics, the work moves beyond descriptive accounts of fossil diversity toward hypothesis-driven tests of adaptation and developmental constraint. A central focus is on how chewing biomechanics may have influenced craniofacial form in early members of Homo and other Pleistocene hominins. By integrating biomechanical scenarios with morphological data, the research aims to evaluate adaptationist explanations for observed variation in the calvaria and face, and to clarify the roles of developmental processes and genetic architecture in producing that variation.

Methodologically, the project employs virtual reconstructions to address the fragmentary nature of many key fossils, enabling comparative analyses that would otherwise be impossible. Quantitative approaches to cranial shape variation are used to characterize morphological differences among specimens and to assess patterns of variation within and between extinct hominin species. Developmental perspectives, particularly studies of calvarial growth in juvenile individuals, contribute to understanding how ontogeny influences adult morphology and how developmental trajectories might vary across taxa. The incorporation of quantitative genetics methods represents a contemporary approach to paleontological inference: by estimating the relationships among traits and the potential for correlated responses to selection, the work can test whether observed morphological patterns are consistent with adaptive change, neutral drift, or developmental constraint.

This research program includes empirical collaboration with field and analytical teams working at important East and southern African fossil localities, notably Gona, Ethiopia and Drimolen, South Africa. These collaborations support the comparative and contextual dimensions of the research, linking fossil evidence from multiple sites to broader questions about evolutionary processes in the Plio-Pleistocene. The project is supported by a National Science Foundation grant (approximately $330,000) targeted to investigate adaptationist scenarios related to chewing biomechanics, indicating a funded effort to combine theoretical, computational, and empirical lines of evidence.

Overall, the study seeks to provide a deeper understanding of craniofacial evolution in early Homo and other Pleistocene hominins by integrating virtual reconstruction, developmental data, quantitative shape analysis, biomechanical modeling, and quantitative-genetic perspectives. By testing specific adaptive hypotheses and situating morphological variation in a developmental and evolutionary framework, the research aims to clarify the mechanisms that generated the diversity of cranial forms in our evolutionary past and to refine interpretations of fossil material that remains fragmentary and complex.