Delezene, LK, Scott, JE, Irish, JD, Villaseñor, A, Skinner, MM, Hawks, J and Berger, LR (2024) Sex-biased sampling may influence Homo naledi tooth size variation. Journal of Human Evolution, 187. p. 103490. ISSN 0047-2484

Text Delezene et al 2024 Accepted Version.pdf - Accepted Version Restricted to Repository staff only until 23 January 2025. Available under License Creative Commons Attribution Non-commercial No Derivatives. Download (1MB)

Abstract

A frequent source of debate in paleoanthropology concerns the taxonomic unity of fossil assemblages, with many hominin samples exhibiting elevated levels of variation that can be interpreted as indicating the presence of multiple species. By contrast, the large assemblage of hominin fossils from the Rising Star cave system, assigned to Homo naledi, exhibits a remarkably low degree of variation for most skeletal elements. Many factors can contribute to low sample variation, including genetic drift, strong natural selection, biased sex ratios, and sampling of closely related individuals. In this study, we tested for potential sex-biased sampling in the Rising Star dental sample. We compared coefficients of variation for the H. naledi teeth to those for eight extant hominoid samples. We used a resampling procedure that generated samples from the extant taxa that matched the sample size of the fossil sample for each possible Rising Star dental sex ratio. We found that variation at four H. naledi tooth positions—I2, M1, P4, M1—is so low that the possibility that one sex is represented by few or no individuals in the sample cannot be excluded. Additional evidence is needed to corroborate this inference, such as ancient DNA or enamel proteome data, and our study design does not address other potential factors that would account for low sample variation. Nevertheless, our results highlight the importance of considering the taphonomic history of a hominin assemblage and suggest that sex-biased sampling is a plausible explanation for the low level of phenotypic variation found in some aspects of the current H. naledi assemblage.

Item Type:	Article
Additional Information:	Lucas K. Delezene, Jeremiah E. Scott, Joel D. Irish, Amelia Villaseñor, Matthew M. Skinner, John Hawks, Lee R. Berger, Sex-biased sampling may influence Homo naledi tooth size variation, Journal of Human Evolution, Volume 187, 2024, 103490, ISSN 0047-2484, https://doi.org/10.1016/j.jhevol.2023.103490. (https://www.sciencedirect.com/science/article/pii/S0047248423001690)
Uncontrolled Keywords:	0603 Evolutionary Biology; 1601 Anthropology; 2101 Archaeology; Anthropology
Subjects:	C Auxiliary Sciences of History > CC Archaeology G Geography. Anthropology. Recreation > GE Environmental Sciences G Geography. Anthropology. Recreation > GN Anthropology Q Science > QH Natural history > QH301 Biology
Divisions:	Biological & Environmental Sciences (from Sep 19)
Publisher:	Elsevier
SWORD Depositor:	A Symplectic
Date Deposited:	12 Feb 2024 14:41
Last Modified:	12 Feb 2024 14:45
DOI or ID number:	10.1016/j.jhevol.2023.103490
URI:	https://researchonline.ljmu.ac.uk/id/eprint/22595

View Item