Mechanical compensation in the evolution of the early hominin feeding apparatus
Year: 2022
Type: article
Abstract: Australopiths, a group of hominins from the Plio-Pleistocene of Africa, are characterized by derived traits in their crania hypothesized to strengthen the facial skeleton against feeding loads and increase the efficiency of bite force production. The crania of robust australopiths are further thought to be stronger and more efficient than those of gracile australopiths. Results of prior mechanical analyses have been broadly consistent with this hypothesis, but here we show that the predictions of the hypothesis with respect to mechanical strength are not met: some gracile australopith crania are as strong as that of a robust australopith, and the strength of gracile australopith crania overlaps substantially with that of chimpanzee crania. We hypothesize that the evolution of cranial traits that increased the efficiency of bite force production in australopiths may have simultaneously weakened the face, leading to the compensatory evolution of additional traits that reinforced the facial skeleton. The evolution of facial form in early hominins can therefore be thought of as an interplay between the need to increase the efficiency of bite force production and the need to maintain the structural integrity of the face.
Authors: Justin A. Ledogar, Sascha Senck, Brian A. Villmoare, Amanda L. Smith, Gerhard W. Weber, Brian G. Richmond, Paul C. Dechow, Callum F. Ross, Ian R. Grosse, Barth W. Wright, Qian Wang, Craig Byron, Stefano Benazzi, Kristian J. Carlson, Keely B. Carlson, Leslie C. Pryor McIntosh, Adam van Casteren, David S. Strait
Institutions: East Tennessee State University, University of Applied Sciences Upper Austria, University of Nevada, Las Vegas, Pacific Northwest University of Health Sciences, University of Vienna, Texas A&M University, University of Chicago, University of Massachusetts Amherst, University of Kansas Medical Center, Mercer University, University of Bologna, University of Southern California, University of the Witwatersrand, Philadelphia College of Osteopathic Medicine, University of Manchester, Washington University in St. Louis, University of Johannesburg
Language: English
Subfield: Anthropology
Field: Social Sciences
Domain: Social Sciences
Open Access status: green
OpenAlex ID: W4282942877