New Evidence for Significant Use of Bitumen in Middle Palaeolithic Technical Systems at Umm el Tlel (Syria) around 70,000 BP

Abstract

Mousterian tools with traces of bitumen on their surfaces discovered at Umm el Tlel (Syria) have been dated to 40,000 years (BP). Until now tools with traces of bitumen were known only from the 8th millennium BC, but this new discovery shows usage 30,000 years earlier. Mousterian complex VI 3, dated to 71,000-72,000 BP, has yielded fragments of black cobbles and eleven Levallois artefacts with traces of black material demonstrated to be bituminous. Herein we present the geochemical and microscopy results on materials from artefact and a cobble. Gas chromatography-mass spectrometry analysis of both C 15+ alkanes and C 15+ aromatics demonstrates that the black substance is natural asphalt. The source of this asphaltic material or bitumen found on the tools is related to natural outcrops located around 40 km east of Umm el Tlel in the Bichri Massif. For the fi rst time, microscopic analysis of 300 Levallois artefacts with no macro-traces of bitumen visible to the naked eye, has demonstrated that two-thirds of these artefacts have black micro-residues. These micro-traces that were identifi ed on artefacts recovered from a strata in complex VI 3, have been identified as bitumen-bearing following analyses. Thus, rather than being a material used occasionally, bitumen is shown to be of key importance in the technological system of these populations, hypothesized to have been used as an adhesive to attach hafts made of organic matter or bone to tools. These new results extend the oldest known date for the use of natural bitumen by early hominids from 40,000 BP to 71,000 BP and show that older Middle Palaeolithic populations were already acquainted with the use of bitumen as adhesive to attach hafts to fl int tools or for other similar uses.