New data from the Middle Palaeolithic Cotencher cave (Swiss Jura): site formation, environment, and chronology

Abstract. Cotencher cave is one of the oldest Palaeolithic sites of Switzerland and is known for its rich faunal and Mousterian artefacts, the latter suggesting one or several passages of Neanderthal hunter–gatherer tribes. This interdisciplinary study summarises novel data concerning site formation processes and anthropic attendance of the site. While the lithic artefacts indicate tool production at the site, the faunal remains do not yield any evidence of a link to human occupation. The sedimentary sequence permits us to unravel several important environmental changes that occurred during the Late Pleistocene. The presence of a local glacier around 70 ka (Marine Isotope Stage, MIS 4) is revealed followed by ice-free conditions characterised by alternating soil formation processes and landscape destabilisation during MIS 3. Solifluction processes suggesting recurrent frozen ground were responsible for the displacements of part of the artefacts and faunal remains. Evidence of local glacier development around 36 ka is related to the particular geomorphological conditions of the studied region and shed new light on the complexity of glacier dynamics. The recognition and dating of recurrent hostile glacier landscapes might contribute to understanding the reasons for the Middle and Upper Palaeolithic attendance hiatuses known in the studied region.