TY - JOUR
T1 - A shared pattern of midfacial bone modelling in hominids suggests deep evolutionary roots for human facial morphogenesis
AU - Schuh, Alexandra
AU - Heuzé, Yann
AU - Gunz, Philipp
AU - Berthaume, Michael A.
AU - Shaw, Colin N.
AU - Hublin, Jean Jacques
AU - Freidline, Sarah
N1 - Publisher Copyright:
© 2024 Royal Society Publishing. All rights reserved.
PY - 2024/4/17
Y1 - 2024/4/17
N2 - Midfacial morphology varies between hominoids, in particular between great apes and humans for which the face is small and retracted. The underlying developmental processes for these morphological differences are still largely unknown. Here, we investigate the cellular mechanism of maxillary development (bone modelling, BM), and how potential changes in this process may have shaped facial evolution. We analysed cross-sectional developmental series of gibbons, orangutans, gorillas, chimpanzees and present-day humans (n = 183). Individuals were organized into five age groups according to their dental development. To visualize each species’s BM pattern and corresponding morphology during ontogeny, maps based on microscopic data were mapped onto species-specific age group average shapes obtained using geometric morphometrics. The amount of bone resorption was quantified and compared between species. Great apes share a highly similar BM pattern, whereas gibbons have a distinctive resorption pattern. This suggests a change in cellular activity on the hominid branch. Humans possess most of the great ape pattern, but bone resorption is high in the canine area from birth on, suggesting a key role of canine reduction in facial evolution. We also observed that humans have high levels of bone resorption during childhood, a feature not shared with other apes.
AB - Midfacial morphology varies between hominoids, in particular between great apes and humans for which the face is small and retracted. The underlying developmental processes for these morphological differences are still largely unknown. Here, we investigate the cellular mechanism of maxillary development (bone modelling, BM), and how potential changes in this process may have shaped facial evolution. We analysed cross-sectional developmental series of gibbons, orangutans, gorillas, chimpanzees and present-day humans (n = 183). Individuals were organized into five age groups according to their dental development. To visualize each species’s BM pattern and corresponding morphology during ontogeny, maps based on microscopic data were mapped onto species-specific age group average shapes obtained using geometric morphometrics. The amount of bone resorption was quantified and compared between species. Great apes share a highly similar BM pattern, whereas gibbons have a distinctive resorption pattern. This suggests a change in cellular activity on the hominid branch. Humans possess most of the great ape pattern, but bone resorption is high in the canine area from birth on, suggesting a key role of canine reduction in facial evolution. We also observed that humans have high levels of bone resorption during childhood, a feature not shared with other apes.
KW - bone formation
KW - bone resorption
KW - facial evolution
KW - geometric morphometrics
KW - ontogeny
UR - http://www.scopus.com/inward/record.url?scp=85190904327&partnerID=8YFLogxK
U2 - 10.1098/rspb.2023.2738
DO - 10.1098/rspb.2023.2738
M3 - Article
C2 - 38628118
AN - SCOPUS:85190904327
SN - 0962-8452
VL - 291
JO - Proceedings of the Royal Society B: Biological Sciences
JF - Proceedings of the Royal Society B: Biological Sciences
IS - 2021
M1 - 20232738
ER -