Taphonomic estimates of competition and the role of carnivore avoidance in hominin site use within the Early Pleistocene Olduvai Basin

Charles P Egeland

doi:10.1016/j.quaint.2013.11.021

Abstract

It has become increasingly clear among paleoanthropologists that Early Pleistocene sites sample a diversity of behaviors and no one model is sufficient to explain every collection of archaeological debris. With this comes the realization that hominins reacted to an equally diverse set of ecological parameters, each of which determined to some extent where, when, and how they chose to concentrate, or not concentrate, their activities across ancient landscapes. Competition with, and predation risk from, large carnivores is thought to be an especially critical factor, particularly when large mammal tissues became a component of hominin diets after 2.6 million years ago. Here, the degree to which carnivore avoidance influenced patterns of hominin site use is evaluated with a sample of faunal and lithic assemblages from Beds I and II at Olduvai Gorge, Tanzania. Multivariate measures of bone destruction, as proxies for levels of on-site competition and thus predation risk, show little systematic relationship with patterns of lithic discard and butchery. This suggests that while carnivore avoidance was probably part and parcel of hominin daily life in the Early Pleistocene Olduvai Basin, other considerations such as water, tree cover, dry land, and toolstone played more proximate roles.

Highlights

It is probably safe to say that paleoanthropologists have moved beyond the rather simplistic view that Early Pleistocene archaeological sites, even the seemingly homogenous “living floors” (Leakey, 1971: 258) or “Type C” sites (Isaac, 1978: 95; Isaac and Harris, 1978: 77–78), can be characterized universally as either home bases or stone caches, as either central places or refuges
Levels of carcass destruction offer one means to estimate the degree of competition and, evaluate the importance of carnivore avoidance in hominins' daily routines
Multivariate assessments of carcass destruction from a number of Bed I and II faunal assemblages from Olduvai Gorge range from extremely light to very intense in general, inferred levels of competition are higher among the latter sites

Summary

Introduction

It is probably safe to say that paleoanthropologists have moved beyond the rather simplistic view that Early Pleistocene archaeological sites, even the seemingly homogenous “living floors” (Leakey, 1971: 258) or “Type C” sites (Isaac, 1978: 95; Isaac and Harris, 1978: 77–78), can be characterized universally as either home bases or stone caches, as either central places or refuges. The temptation to treat sites as monolithic entities is strong given that the inferred behavioral correlates of various scenarios of site formation, be it active hunting, regular food-sharing, consistent transport of lithic and faunal material, parental provisioning, or a tightly bonded, family based social organization, set the baseline for what early stone tool using hominins were minimally capable of. This in turn has implications for broader themes in human evolution such as, for example, how (or if) lithic technology and carnivory paved the way for the development of extreme encephalization (Aiello and Wheeler, 1995), superlative colonization abilities (Antón et al, 2002, Foley, 2002, Wells and Stock, 2007), and a truly unique life history (Kaplan et al, 2000, Hill et al, 2009). The latter affordance is of particular interest in this context, as the toolassisted butchery and consumption of carcasses thrust hominins into a diverse guild of African carnivores as would-be competitors and, potentially, increasingly susceptible prey (Turner, 1988, Shipman and Walker, 1989, Brantingham, 1998a, Brantingham, 1998b, Van Valkenburgh, 2001, Pobiner and Blumenschine, 2003)

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Results

Discussion

Conclusion