The endocast morphology of LES1, Homo naledi

Bibliographic Collection: 
Publication Type: Journal Article
Authors: Hurst, Shawn D.; Holloway, Ralph L.; Balzeau, Antoine; Garvin, Heather M.; Vanti, William B.; Berger, Lee R.; Hawks, John
Year of Publication: 2024
Journal: American Journal of Biological Anthropology
Volume: n/a
Issue: n/a
Pagination: e24983
Date Published: 2024/06/12
Publication Language: eng
ISBN Number: 2692-7691
Keywords: Brain, Endocast, Homo naledi, Human evolution, Paleoneurology

Abstract Objectives Homo naledi is near the extreme of small brain size within Homo but is easily recognized as Homo in other aspects of endocast morphology. This study adds new evidence of the endocast morphology of H. naledi by describing the Lesedi Hominin 1 (LES1) endocranium from the Lesedi Chamber and compares it to the previously known H. naledi individual Dinaledi Hominin 3 (DH3) as well as other hominin taxa. Materials and Methods We examined interlandmark distances with both univariate and multivariate methods in multiple hominin taxa and both species of Pan. For each distance, we compared groups using adjusted Z-scores (Azs). Our multivariate analyses included both principal component analyses (PCA) and linear discriminant analyses (LDA). Results DH3 and LES1 each have absolute third frontal convolution measures that enter the upper half of the variation for Homo sapiens, Homo erectus, and Homo neanderthalensis. Examined relative to the cube root of endocranial volume, H. naledi ranks among the highest values in these samples of Homo. Both absolute and relative values for H. naledi specimens are far above Pan, Australopithecus, and Paranthropus, suggesting an expanded Broca's area. Conclusions Both qualitative and quantitative analyses show consistency between LES1 and other H. naledi endocasts and confirm the shared morphology of H. naledi with H. sapiens, H. neanderthalensis, and some specimens of H. erectus.

Short Title: American Journal of Biological Anthropology