Ashley Hammond of the George Washington University was awarded a Leakey Foundation research grant during our spring 2015 cycle for her project entitled “Reconstructing phenotypic change of the pelvis in apes and humans.”
I study how the skeletal anatomy of primates relates to locomotion. The hipbone differs dramatically among living primates adapted for different locomotion, and my research focuses on this bone to identify how, and from which type of ape ancestor, hominin bipedalism evolved. Unfortunately, hipbones are fragile and rarely preserved in the fossil record, leaving us with an incomplete picture of early hominin hipbone evolution.
My goal is to reconstruct the evolution of locomotor behaviors in apes and hominins. My study will model hipbone shape evolution, with a particular focus on furthering our understanding of what the pelvis of the chimpanzee-hominin last common ancestor (LCA) is expected to look like under different evolutionary scenarios. First, I will use 3D shape quantification methods to characterize hipbone shape in primates, testing the hypothesis that living great apes exhibit different hip morphologies. Second, I will reconstruct the expected hipbone morphology of the LCA using phylogenetically-informed quantitative methods incorporating fossil apes (such as Sivapithecus) as calibration points. This portion of my study will provide a rigorous 3D reconstruction of the expected hipbone shape for the LCA and allow me to evaluate claims that the LCA had a chimpanzee-like hipbone. Finally, I will model the evolutionary scenario with the highest statistical support that explains how modern ape and human hipbones evolved.
L to R: Louise Leakey, Ashley Hammond, Meave Leakey
With financial support from the Leakey Foundation, my study will shed light on hipbone shape evolution in apes and humans, and provide key insights about origins of human locomotion.
Mountain gorilla (Gorilla beringei) pelvis
The following are three-dimensional PDF images of gorilla and baboon pelvises. Right click to save the PDFs then use Adobe Reader or Acrobat to view and interact with the image: