Identifying the Levant as a potential contact and interbreeding zone for Neanderthals and modern humans

Abstract

Timing of interbreeding between modern humans and Neanderthals has been subject of numerous studies but its geography remains largely unknown. Genetic evidence suggests three different interbreeding events: first in the Marine Isotope Stage (MIS) 7 ([~]250 to 200 ka), then in the MIS5 ([~]100 to 120 ka) and the final event in the MIS3 ([~]60 to 50 ka). Here, we used all known archaeological sites between 60-50 ka associated with Neanderthals and modern human presence and a set of paleoenvironmental data to reconstruct Neanderthals and modern humans habitat suitability using the Species Distribution Modeling (SDM) techniques. Assessing geographical overlap between the two species, we identify potential interbreeding zone. We found that the Levant was main potential interbreeding area of the third event. Previous research has identified the Zagros Mountains in Iran as a potential interbreeding zone during the second interbreeding event MIS5 ([~]100 to 120 ka). Compiling the results of this study to previous research can help us to better understand the dynamics of modern humans and Neanderthals interbreeding over both time and space. The two potential interbreeding areas have high priority for future research.