Level U3.1, a new archaeological level discovered at BK (upper bed II, Olduvai Gorge) with evidence of megafaunal exploitation

Abstract

Excavations at Bell Korongo (BK) have yielded important evidence to infer different behaviours of early hominins in several archaeological levels since 1935. The present study shows the results for a newly geological and archaeological of BK (Level U3.1). This paper describes the geology of this newly discovered level, along with a taphonomical analysis of the archaeological remains to better understand the assemblage formation processes. This new level was deposited at the base of LA Unit 3, in decantation facies over a point-bar. Although these facies, found throughout the site furnish ideal conditions for preservation, this is the first time in BK level U3.1 that any archaeological or paleontological remains have been found embedded within them. The taphonomic study suggests that the assemblage is the result of a short time span involving processes accumulating remains from different thanatocoenoses created over a time span of less than one year, consistent with a sedimentation process triggered by flooding of the channel during the annual heavy rains in the wet season. Furthermore, a large percentage of bones, including megafaunal remains, appear cutmarked, percussion marks and anthropgenic green fractures. Level U3.1 is the youngest level at BK, and adds to the evidence of the megafaunal exploitation behaviour of early Pleistocene hominins, which has already been extensively reported in BK Levels 4 and 5 and other African Lower Pleistocene sites.