Yeganeh Sekhavati

Grant Type

Dissertation Fieldwork Grant

Institutional Affiliation

Washington U., St. Louis

Grant number

Gr. 10244

Approve Date

October 7, 2021

Project Title

Sekhavati, Yeganeh (Washington U., St. Louis) "The evolution of bipedalism in phylogenetic and environmental contexts"

Bipedalism is a key human adaptation, and the acquisition of bipedalism was a major event in human origins and evolution. Despite consensus about these notions, there is less agreement about the nature of the transition to bipedality. One approach to evaluating hypotheses about the origin and evolution of bipedalism is to incorporate phylogeny. Analyzing character evolution in a phylogenetic framework allows us to better understand the historical pathways of characters that are functionally related to bipedalism and to examine how these traits evolved. Furthermore, it provides the context necessary to evaluate potential linkages between hominin evolution and environmental change. This study analyzes the evolution of postcranial characters related to bipedalism and examines their pattern of character evolution, and the ecological, temporal, and geographical contexts in which those characters evolved. Patterns of character evolution will be analyzed using maximum parsimony and Bayesian inference. Random and non-random evolutionary models will be compared to discern which model provides the best approximate explanation of the data. Moreover, the relative strength of each model will be further assessed using Akaike weights, which estimate the relative likelihood of the model, given the data.