Finite element models presented from: Bite force production and the origin of Homo

The divergence of Homo from gracile australopiths has been described as a trend of decreasing dentognathic size and robusticity, precipitated by stone tool use and/or a shift to softer foods, including meat. Yet, mechanical evidence supporting this narrative is sparse, and isotopic and archaeological data have led to the suggestion that a shift away from a gracile australopith-like diet would not have occurred in the most basal members of Homo but rather only with the appearance of H. erectus, implying that the origin of our genus is not rooted in dietary change. Here, we provide mechanical evidence that H. habilis exhibits an australopith-like pattern of facial strain during biting but, unlike most australopiths, was not suited for a diet that required forceful processing by the molar teeth. H. habilis was at elevated risk of distractive jaw joint forces during those bites, constraining muscle recruitment so as to avoid generating uncomfortable/dangerous levels of tension in the j..., , , # Finite element models presented in: Bite force production and the origin of Homo by Ledogar et al.

Dataset DOI: [10.5061/dryad.j0zpc86k6](10.5061/dryad.j0zpc86k6)

## Description of the data and file structure

README file accompanying the Finite Element Models presented in “BITE FORCE PRODUCTION AND THE ORIGIN OF *HOMO*” by Ledogar et al.

Cranial finite element models are provided for four fossil hominin specimens (KNM-ER 1813, AL 444-2, MH1, OH5, Sts 5), six specimens of *Pan troglodytes* (PC1-, PC1+, PC2-, PC2+, PC3-, PC3+), and seven specimens of modern *Homo sapiens* (BERG, GRGL, KSAN1, KSAN2, MALP, TIGA, WAFR).

Each of these 18 models has been subjected to two loading conditions, one simulating a maximal bite on the third premolar (P3), and one on the second molar (M2). For each bite case, we subjected each FEM to isometrically scaled muscle forces derived from a chimpanzee (*Pan troglodytes*) simulating a maximal bite (all muscles contracting at peak activity). FEMs of moder...,