Population and Territorial State Dynamics in the Northern Levant
In contrast to the rest of Anatolia, the Northern Levant stands out as a region of the Near East with traceable post-Neolithic changes in the genetic structure. We found that the gene pools at Ebla and Alalakh can only be explained by more complex models that require additional contributions both from the Caucasus and Southern Levant. The inclusion of a source related to the Caucasus in our proposed model raises the question whether this turnover could be linked to the expansion of the Transcaucasian Kura-Araxes material culture to the Levant. This expansion is recorded in the region of the Northern Levant ca. 2800 BCE and could be associated with the movement/ migration of people from Eastern Anatolia and the Southern Caucasian highlands (Greenberg and Palumbi, 2015; Greenberg et al., 2014). However, our results do not support this scenario for a number of reasons: (1) we do not find any substantial increase of Caucasus-related ancestry in the populations of the primary expansion area of Kura-Araxes (e.g., Eastern Anatolia), (2) populations from the highlands of the Southern Caucasus— including individuals from a Kura-Araxes context (‘‘L.Caucasu- s_EBA’’)—as secondary source populations also fail, and (3) so do models with Arslantepe from Eastern Anatolia, a population located mid-way along the proposed expansion route from the Southern Caucasus to the Northern Levant.
Consequently, these interpretative caveats call for consideration of alternative historical scenarios, including scenarios of multiple gene-flow events that could have taken place in the intervening two millennia between the Tell Kurdu population and those of Bronze Age Ebla and Alalakh. However, written sources, archaeological, and paleoclimatic evidence suggest that a narrower time period—the end of the EBA—had been very critical with respect to political tensions and population mobility. It was during this period, for example, that Ebla was destroyed twice and reestablished at the beginning of MBA. There are extensive textual references from the end of the EBA through the LBA referring to groups of people arriving into the area of the Amuq Valley. Although these groups were named, likely based on designations (e.g., Amorites, Hurrians), the formative context of their (cultural) identity and their geographic origins remain debated. One recent hypothesis (Weiss, 2014, 2017; Akar and Kara, 2020) associates the arrival of these groups with climate-forced population movement during the ‘‘4.2k BP event,’’ a Mega Drought that led to the abandonment of the entire Khabur river valley in Northern Mesopotamia and the search of nearby habitable areas.
Taking the above into consideration, we suggest that the ancestries we inferred for Alalakh and Ebla might best describe the genetic make-up of the EBA populations of unsampled Northern Mesopotamia. During the following MBA and LBA, we find no evidence of genetic disruption, even though shifts in territorial control dynamics between kingdoms/empires affected Ebla’s and Alalakh’s socio-cultural development (see STAR Methods).
Nevertheless, the case of the Alalakh individual with likely Central Asian origin is a finding that can be interpreted within the context of nascent internationalism of the Middle and Late Bronze Age Eastern Mediterranean societies. It calls for future research on the various societal features of this phenomenon and how these are reflected on the individual life histories.