HUMAN AND ANIMAL FOOTPRINTS (1.5 MA) FROM NORTHERN KENYA: METHODS

In 2009 Bennett et al. (Science, 323) reported on animal and hominin footprints from East Africa dated to 1.5 million years old. The main site described in this paper (FwJj14E) is located close to Ileret in northern Kenya and the hominin prints have been attributed to Homo erectus. They appear to have a modern foot anatomy and style of locomotion providing new insight into the evolution of human gait. The hominin prints occur in association with a range of animal prints providing information on the faunal community and the paleo-environmental context of the hominins. Here we provide the geological context for this site and for a younger site (1.4 Ma; GaJi10) located 45 km to the south which also contains hominin prints but a different animal print assemblage. Both sites are from the Okote Member, part of the Koobi Fora Formation and were deposited on the floor of the East African rift in a low energy deltaic system. The extent of the lacustrine environment is unknown; it may represent a relatively small playa lake or a more substantial water body within the floor of the rift. Each of the two footprint sites represents a different depositional component of this deltaic system and provides important insight into the nature of the paleo-environments being occupied by hominins at this time. This paper not only examines the sedimentological context of the prints but also explores the application of optical laser scanning in the preservation and analysis of trace fossils; an approach which is instrumental in the analysis of both these unique and fragile trace fossil sites.