Lower Ilium Evolution in Apes and Hominins

This study examines the variation in relative lower ilium height between and within living and fossil hominoid species (and other anthropoids), and models its evolution using available fossil hominoids as calibration points. We find nuanced differences in relative lower ilium height among living hominoids, particularly in regards to gorillas, which do not have elongate lower ilia (because they are likely to represent the plesiomorphic hominoid condition for this trait). We also show that differences in relative lower ilium height among hominoid taxa are not readily explained by differences in size between species. Our maximum likelihood ancestral state reconstructions support inferences that chimpanzees (Pan troglodytes in particular) and orangutans evolved their elongate lower ilia independently. We also find that the predicted lower ilium height of the Pan‐Homo LCA is shorter than all great apes except gorillas. This study adds to a growing body of evidence that finds different regions of the body show different evolutionary histories in different hominoids, and underscores that the unique combinations of morphologies of each modern and fossil hominoid species should be considered when reconstructing the mosaic nature of the Pan‐Homo LCA. Anat Rec, 300:828–844, 2017. © 2017 Wiley Periodicals, Inc.
Source: The Anatomical Record Part A: Discoveries in Molecular, Cellular, and Evolutionary Biology - Category: Molecular Biology Authors: Tags: Special Issue Article Source Type: research