OH 89: A newly described ~1.8-million-year-old hominid clavicle from Olduvai Gorgeuse asterix (*) to get italics

Catherine E. Taylor, Fidelis Masao, Jackson K. Njau, Agustino Venance Songita, Leslea J. HluskoPlease use the format "First name initials family name" as in "Marie S. Curie, Niels H. D. Bohr, Albert Einstein, John R. R. Tolkien, Donna T. Strickland"

2023

<p>Objectives: Here, we describe the morphology and geologic context of OH 89, a ~1.8-million-year-old partial hominid clavicle from Olduvai Gorge, Tanzania. We compare the morphology and clavicular curvature of OH 89 to modern humans, extant apes, and a sample of other hominid fossil clavicles. Materials and Methods: Comparative samples include 25 modern human clavicles, 30 Gorilla, 30 Pan, 10 Papio, and five hominid clavicles. Length regression on midshaft size using the extant comparative samples is used to estimate the total length of OH 89. A set of 9 linear measurements are taken from each individual. We also describe a new methodology for measuring clavicular curvature using measurements of sternal and acromial curvature, from which an overall curvature measurement is calculated. A principal component analysis (PCA) and a t-distributed stochastic neighbor embedding (t-SNE) analysis are used to compare the morphology of OH 89 with the extant and fossil comparative samples. Results: Our new method of measuring clavicular curvature successfully separates the different genera of the extant clavicles. The length estimate and sternal and acromial curve measurements for OH 89 falls within the larger male humans. The PCA shows OH 89 and most of the fossil hominids falling between the modern human and Pan groups, while the t-SNE suggests that OH 89, KSD-VP-1/1, KNM-ER 1808, and OH 48 are more similar to each other than to any of the other groups. This analysis also plots KNM-WT 15000 with the modern humans and Krapina 158 with the Pan individuals. Discussion: The OH 89 clavicle derives from an individual of unknown hominid species with a shoulder breadth similar to that of a large human male. The curvature of OH 89 is relatively human-like relative to its length. Our new methodology for measuring clavicular curvature, combined with the utilization of t-SNE analyses, provides greater separation of genera than previously used methods, and wider use of t-SNE may be useful in paleoanthropological work.</p>

https://doi.org/10.6084/m9.figshare.22050185.v1You should fill this box only if you chose 'All or part of the results presented in this preprint are based on data'. URL must start with http:// or https://

https://doi.org/10.6084/m9.figshare.22054280.v1You should fill this box only if you chose 'Scripts were used to obtain or analyze the results'. URL must start with http:// or https://

paleontology, evolution, paleoanthropology, Pleistocene, variation

NonePlease indicate the methods that may require specialised expertise during the peer review process (use a comma to separate various required expertises).

Comparative anatomy, Evolutionary biology, Fossil record, Methods, Morphological evolution, Paleoanthropology, Vertebrate paleontology

Faysal Bibi (Faysal.Bibi@mfn.berlin), Maria Rebecca Garcia Gonzalez (mrgarcia@ubu.es), Habiba Chirchir (chirchir@marshall.edu ) No need for them to be recommenders of PCIPaleo. Please do not suggest reviewers for whom there might be a conflict of interest. Reviewers are not allowed to review preprints written by close colleagues (with whom they have published in the last four years, with whom they have received joint funding in the last four years, or with whom they are currently writing a manuscript, or submitting a grant proposal), or by family members, friends, or anyone for whom bias might affect the nature of the review - see the code of conduct

2023-02-08 19:45:01

Nuria Garcia