Extant Humans & Primates

Paleoanthropologists at UC Davis conduct research on extant humans and extant non-human primates to inform their understanding of human evolution and to better understand biological variation in humans and other primates. This research is currently being guided by specific research questions.

How does hybridization affect the phenotype and genotype in primates? Members of Prof. Weaver’s lab are studying the genome and skeletal morphology of a colony of crosses between Indian and Chinese Rhesus macaques. They have collected a variety of data types, including medical images (CT scans), dental molds, and low-coverage complete genome sequences. This data is being used to investigate genomic questions, such as natural selection for or against Chinese- or Indian-derived DNA, and phenotypic questions, such as the morphological signatures of hybridization.

How are patterns of (co)variation among morphological traits associated with the evolution of novel skeletal morphologies? Members of Prof. Jung’s lab investigate how variational properties (e.g., morphological integration and modularity) are associated with the evolution of novel skeletal morphologies using evolutionary quantitative genetic methods. For example, this research examines how directional selection acting on developmental and/or functional modules—particularly those with pervasive effects on other traits—generates correlated evolutionary responses among skeletal elements and contributes to, and may facilitate, the evolution of novel morphological traits. Ultimately, this study aims to develop a broader comparative framework for understanding how patterns of integration, modularity, and correlated evolution influence the evolution of novel skeletal forms across diverse primate lineages.

How are ontogenetic and evolutionary changes in primate skull morphology associated with feeding biomechanics? Members of Prof. Jung’s lab investigate how skull morphology relates to feeding biomechanics across both ontogenetic and evolutionary timescales. By analyzing biomechanically informative skull measurements, this research examines how skull morphology is shaped by developmental constraints, feeding biomechanics, and phylogenetic history. For example, by assessing changes in covariation patterns among skull regions across ontogeny and across diverse primate lineages, this research aims to elucidate how developmental and functional processes contribute to the emergence of adult cranial morphology and the evolution of feeding system adaptations.

How are phylogenetic history and positional behaviors associated with the evolution of the primate axial–pelvic complex? Members of Prof. Jung’s lab study the evolutionary relationships among phylogenetic history, positional behaviors (i.e., locomotion and posture), and morphological variation in the axial–pelvic complex (i.e., skull, vertebral column, and os coxae). By integrating functional morphological principles with traditional and geometric morphometric datasets and applying a suite of phylogenetic comparative approaches, this research examines how evolutionary history and locomotor adaptations have shaped skeletal morphological diversity among primates.