Sergio Almecija

SERGIO ALMECIJA, George Washington University, Washington, DC, was awarded a grant in October 2016 to aid research on ‘Phylogenetic Inference in Hominoids Using Multiple Hard-tissue 3D Morphologies.’ Elucidating the phylogenetic relationships between living and fossil hominoid species is essential to understanding the tempo and mode of ape and human evolution. However, theories for human origins are currently limited because it is difficult to infer the phylogenetic signals reflected by hard tissue morphologies, leading to disagreements about the evolutionary role played by different fossil species. During the research undertaken during this grant, a high-resolution 3D database representing 70 elements across all regions of the skeleton was built for living hominoids and selected anthropoids. Subsequently, preliminary geometric morphometric data were collected from 13 anatomical structures in a pilot sample of eight species representing the entire African ape and human clade plus orangutans, hylobatids and a macaque (out-group). ‘Phylogenetic morphometric’ analyses indicate that the best tree obtained by simultaneously analyzing all the landmark configurations plus ‘classic’ hard-tissue characters resulted in a tree matching the molecular phylogeny of great apes and humans. These results demonstrate that the proposed approach works ‘especially given that only ~25% of the targeted structures were included in the pilot analysis. Thus, this project shows a major promise for elucidating the relative position of key fossils hominoids and thus test currently debated evolutionary hypotheses in human evolution.