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DOE OSTI · 3385033

Paleotribological models using preserved fossil tissue properties reveal functional significance of Eurasian mammoth dental evolution

Grejtak, Tomas [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States); Lehigh University, Bethlehem, PA (United States); Florida State University, Tallahassee, FL (United States)] (ORCID:0000000209951166)·Hunt, Tyler C. [Florida State University, Tallahassee, FL (United States); Purdue University, West Lafayette, IN (United States)]·Whalen, Niall S. [Florida State University, Tallahassee, FL (United States)] (ORCID:0000000197321182)·Hendricks, Stephen K. [Florida State University, Tallahassee, FL (United States)]·Babuska, Tomas F. [Lehigh University, Bethlehem, PA (United States); Florida State University, Tallahassee, FL (United States)]·Craig, Robert L. [Florida State University, Tallahassee, FL (United States)]·Varma, Soumya [Iowa State University, Ames, IA (United States); KLA Corporation, Milpitas, CA (United States)] (ORCID:0000000336914915)·Jia, Xiu [Lehigh University, Bethlehem, PA (United States)]·Norell, Mark A. [American Museum of Natural History (AMNH), New York, NY (United States)]·Pathak, Siddhartha [Iowa State University, Ames, IA (United States)] (ORCID:0000000324019964)·Vermaak, Natasha [Lehigh University, Bethlehem, PA (United States)] (ORCID:0000000240777960)·Druckenmiller, Patrick S. [University of Alaska Museum, Fairbanks, AK (United States)] (ORCID:0000000151378378)·Erickson, Gregory M. [Florida State University, Tallahassee, FL (United States)]·Krick, Brandon A. [Florida State University, Tallahassee, FL (United States); Florida A & M University, Tallahassee, FL (United States)] (ORCID:0000000331915433)
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Abstract

Eurasian mammoths (Mammuthus) underwent substantial modifications in molar morphology as later-diverging species evolved progressively thinner enamel and increased enamel crest complexity. These features have been hypothesized to reduce whole-tooth wear and extend dental longevity as increasingly graze-dominated diets evolved within the lineage. This hypothesis has yet to be directly tested. Here, in this study, we developed an in-silico wear model using experimentally derived wear rates from fossil and extant proboscidean dental tissues. The models revealed that shifts in tissue topology do not affect whole-tooth wear rate, as inverse trends in lamellar frequency and enamel thickness preserve a consistent surface enamel area fraction; the determining factor of wear. Rather, topological shifts produce a wear-emergent secondary occlusal surface with greater numbers of triturating crests that create a regular, low-relief, file-like shearing pavement. These changes in occlusal architecture likely directly impacted the mastication capacity of Mammuthus dentitions, facilitating their dietary expansion to incorporate fibrous, lower-nutrient graze.

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Grejtak, Tomas [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States); Lehigh University, Bethlehem, PA (United States); Florida State University, Tallahassee, FL (United States)] (ORCID:0000000209951166), Hunt, Tyler C. [Florida State University, Tallahassee, FL (United States); Purdue University, West Lafayette, IN (United States)], Whalen, Niall S. [Florida State University, Tallahassee, FL (United States)] (ORCID:0000000197321182), Hendricks, Stephen K. [Florida State University, Tallahassee, FL (United States)], Babuska, Tomas F. [Lehigh University, Bethlehem, PA (United States); Florida State University, Tallahassee, FL (United States)], Craig, Robert L. [Florida State University, Tallahassee, FL (United States)], Varma, Soumya [Iowa State University, Ames, IA (United States); KLA Corporation, Milpitas, CA (United States)] (ORCID:0000000336914915), Jia, Xiu [Lehigh University, Bethlehem, PA (United States)], Norell, Mark A. [American Museum of Natural History (AMNH), New York, NY (United States)], Pathak, Siddhartha [Iowa State University, Ames, IA (United States)] (ORCID:0000000324019964), Vermaak, Natasha [Lehigh University, Bethlehem, PA (United States)] (ORCID:0000000240777960), Druckenmiller, Patrick S. [University of Alaska Museum, Fairbanks, AK (United States)] (ORCID:0000000151378378), Erickson, Gregory M. [Florida State University, Tallahassee, FL (United States)], Krick, Brandon A. [Florida State University, Tallahassee, FL (United States); Florida A & M University, Tallahassee, FL (United States)] (ORCID:0000000331915433). 2026-07-01. Paleotribological models using preserved fossil tissue properties reveal functional significance of Eurasian mammoth dental evolution. https://doi.org/10.1016/j.actbio.2026.05.040

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