Sergio Almecija

Grant Type

Post PhD Research Grant

Institutional Affiliation

George Washington U.

Grant number

Gr. 9364

Approve Date

October 7, 2016

Project Title

Almecija, Dr. Sergio, George Washington U., Washington, DC - To aid research on 'Phylogenetic Inference in Hominoids Using Multiple Hard-tissue 3D Morphologies'

Preliminary abstract: Elucidating the phylogenetic relationships between living and fossil hominoid species is essential to understanding the tempo and mode of ape and human evolution. For example, molecular evidence indicates that chimpanzees are the closest living relatives of humans, leading many to assume that the last common ancestor (LCA) of Pan and Homo looked like Pan. However, defining precisely the phylogenetic position of particular fossil apes (e.g., Sivapithecus), and early members of the human clade (e.g., Ardipithecus), could drastically change human evolutionary theories by more accurately calibrating primitive versus derived morphologies in each lineage. Theories for human origins are currently limited because it is difficult to infer the phylogenetic and functional signals reflected by complex hard tissue morphologies, leading to disagreements about the evolutionary role played by different fossil taxa. The objective of the proposed project is to generate a thorough morphometric protocol for the phylogenetic analysis of humans and apes from high-resolution 3D phenotypic (shape) data from different skeletal structures. Shape and size phenotypic data (based on geometric morphometrics) for each great ape species, humans, and selected hylobatid and anthropoid species will be incorporated in novel algorithms developed by members of the team to re-produce the molecular modern hominoid phylogeny. This study will then systematically evaluate which morphometric data (i.e., which bones, regions of bones, which landmarks, and combinations of these variables) derived from skeletal phenotypes approximate the molecular phylogeny. The data gathered from this experimental design will finally allow us to incorporate fragmentary fossils in phylogenetic tree reconstruction, which is crucial for testing evolutionary scenarios for ape and hominin evolution.