Reassessing the role of carnivores in the formation of FLK North 3 (Olduvai Gorge, Tanzania): A pilot taphonomic analysis using Artificial Intelligence tools

Abstract

FLK North (FLK N) (Bed I, Olduvai Gorge, Tanzania) is one of the best examples of a palimpsest where felids, hyenids and hominins made use of the same space without or with minimal interaction between hominins and the other two carnivores. Felids have been interpreted as the main accumulators and carcass consumers followed by frequent hyenid intervention. The presence of hominins at this site has been documented through the discovery of stone tools. Here, we test previous taphonomic interpretations of this site through the application of Artificial Intelligence (AI) tools (computer vision applied to bidimensional images of tooth pits) to taxonomically discriminate carnivore-made tooth marks. The bones we analyzed constitute a small sample, being a preliminary study of bone surface modifications (BSM) through the application of AI to a sample of the FLK N archaeofaunal assemblage (mostly to Level 3 fossils), pending access to the larger excavated collections. The results obtained in the present study show that the marks analyzed have been generated both by hyenids and felids. The slight predominance of hyena tooth marks is expected, since the bone sample used is dominated by long limb bones, and hyenas are the most likely agent causing long bone breakage, although felids also break bones of carcasses smaller than 150 kg as documented in the site. Felid impact, in at least three cases, is documented with tooth marks imprinted by felids and hyenas occurring on the same specimens. Felid-hyenid interaction is, thus, documented though the deep learning methods applied. The limited number of specimens where both agents are documented suggest that both hyenids and felids were independently breaking a substantial part of the bones at FLK N. This preliminarily modifies previous interpretations that attributed most long bone fragmentation exclusively to hyenas.