The 89th Annual Meeting of the American Association of Physical Anthropologists (2020)

Convergence of innominate morphology in suspensory primates: a 3D geometric morphometrics approach


1Center for the Study of Human Origins, Department of Anthropology, New York University, 2New York Consortium in Evolutionary Primatology

April 18, 2020 , Platinum Ballroom Add to calendar

The bony pelvis is perhaps one of the most complicated structures in the body. Considering its complex structure, using three-dimensional (3D) geometric morphometrics in analyzing shape variation between primate groups is important as it maintains the 3D shape of the innominate. Locomotor modes can vary within and between species, and primates are not restricted to a single style. Platyrrhines are mainly arboreal quadrupeds that also display leaping behaviors. The exception are the atelines, a group of species who use suspensory and climbing behaviors while locomoting and feeding similar to apes, albeit with prehensile tails. The aim of this study is to investigate if there is convergence in shape of the pelvis in suspensory primates, and to elucidate what factors (such as function, phylogeny, and/or allometry) might be driving variation in shape. Following Lewton (2015), 3D landmarks were collected from a range of anthropoid primates (n=133) with a focus on atelids and hominoids. Results show that the first axis of Procrustes-adjusted variance (accounting for 52% of total shape variation) correlates strongly with centroid size and is therefore driven by allometry. Subsequent axes demonstrate clear separation of locomotor groups. A phylomorphospace analysis shows that Ateles, hylobatids, and some colobines pull away from their respective outgroups in similar directions. Future analyses will include semi-landmarks to better capture the complex shape of the pelvis and the inclusion of fossil pelves to test hypotheses of locomotor behavior in extinct primates.

This material is based upon work supported by the NSF-GRFP under Grant No. 1839302 to MVA, NSF GRFP-1650895 to JE, and a Leakey Foundation Grant to SAW.

Slides/Poster (pdf)