On Time Scales and “synchronic” Variability in the Archaeology of Human Origins: Short-Term Technological Variations at SHK (olduvai Gorge, Tanzania)

The significance of the archaeological record unearthed in the SHK fluvial landscape represents a noteworthy dataset to study in greater detail the expression of inter-assemblage variability during the formally labelled Developed Oldowan/Acheulean interface in Olduvai Gorge. A precise stratigraphic interval, laterally continuous, and preserving fractions of anthropogenic activity at different points of the same fluvial network makes it feasible to identify the variable techno-economic ways in which hominins responded to the local paleo-landscape in a short time unit. In this work we present the results of the comparative techno-economic study of the three lithic collections retrieved from the time unit defined by an isochronous litho-stratigraphic volcanic horizon deposited in the fluvial landscape of SHK Main site and SHK Extension. The combined use of this isochrone plus the archaeo-stratigraphic method to refine time-averaging constraints offers for the first time an assessment of the nature of technological variation within different fractions of the same fluvial landscape at 1.5 Ma in Middle Bed II. The goal of this analysis is to look closely at inter-assemblage variability in a unit of time with a coherent degree of synchronicity and to add new data to the Developed Oldowan/Acheulean gradient.