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Abstract Multiple lines of genetic and archaeological evidence suggest that there were major demographic changes in the terminal Late Pleistocene epoch and early Holocene epoch of sub-Saharan Africa 1–4 . Inferences about this period are challenging to make because demographic shifts in the past 5,000 years have obscured the structures of more ancient populations 3,5 . Here we present genome-wide ancient DNA data for six individuals from eastern and south-central Africa spanning the past approximately 18,000 years (doubling the time depth of sub-Saharan African ancient DNA), increase the data quality for 15 previously published ancient individuals and analyse these alongside data from 13 other published ancient individuals. The ancestry of the individuals in our study area can be modelled as a geographically structured mixture of three highly divergent source populations, probably reflecting Pleistocene interactions around 80–20 thousand years ago, including deeply diverged eastern and southern African lineages, plus a previously unappreciated ubiquitous distribution of ancestry that occurs in highest proportion today in central African rainforest hunter-gatherers. Once established, this structure remained highly stable, with limited long-range gene flow. These results provide a new line of genetic evidence in support of hypotheses that have emerged from archaeological analyses but remain contested, suggesting increasing regionalization at the end of the Pleistocene epoch.
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Archaeological Recovery of Late Pleistocene Hair and Environmental DNA from Interior Alaska
Ancient hair and remnant plant DNA are important environmental proxies that preserve for millennia in specific archaeological contexts. However, recovery has been rare from late Pleistocene sites and more may be found if deliberately sought. Once discovered, singular hair fragments are not easily identified to taxa through comparative analyses and environmental DNA (eDNA) extraction can be difficult depending on preservation or contamination. In this paper, we present our methods for the combined recovery of ancient hair specimens and eDNA from sediments to improve our understanding of late Pleistocene environments from the Holzman site along Shaw Creek in interior Alaska. The approach serves as a useful case study for learning more about local environmental changes.
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- Award ID(s):
- 1850949
- PAR ID:
- 10323602
- Date Published:
- Journal Name:
- Environmental Archaeology
- ISSN:
- 1461-4103
- Page Range / eLocation ID:
- 1 to 16
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1080/14614103.2022.2031836
