Ecosystemevolution and hominin paleobiology at East Turkana, northern Kenya between 2.0 and 1.4 Ma

Abstract

Over the past five decades, fossil deposits within the Upper Burgi, KBS and Okote members at East Turkana in northern Kenya have providedmany important insights into hominin behavior and ecology during a critical period in hominin evolution between 2.0 and 1.4Ma. In this study, we use a large compilation of faunal abundance data frompaleontological and archaeological collections at East Turkana dating to this timeinterval to investigate temporal patterns in large mammal taxa, ecosystem evolution and hominin ecology. Our analyses indicate that although portions of the ecosystem were dominated by mesic grasslands, the relative proportion of mesic and arid grassland environments varied though time. We document a major transition in the family Suidae with an increase in the abundance of fossils attributed to the Metridiochoerus lineage coeval with the local extinction of the Notochoerus lineage and decline in abundance of the Kolpochoerus lineage. Finally, by comparing the proportional representation of mammalian taxa found in paleontological collections versus those found in archaeological collections, our data suggest that archaeological sites at East Turkana, particularly those c.1.5 Ma, contain disproportionately large numbers of alcelaphin bovid remains. This could reflect 1) hominin prey choice, 2) hominin hunting/scavenging habitat choice, or 3) a combination the two.