Archaeologists increasingly use large radiocarbon databases to model prehistoric human demography (also termed paleo-demography). Numerous independent projects, funded over the past decade, have assembled such databases from multiple regions of the world. These data provide unprecedented potential for comparative research on human population ecology and the evolution of social-ecological systems across the Earth. However, these databases have been developed using different sample selection criteria, which has resulted in interoperability issues for global-scale, comparative paleo-demographic research and integration with paleoclimate and paleoenvironmental data. We present a synthetic, global-scale archaeological radiocarbon database composed of 180,070 radiocarbon dates that have been cleaned according to a standardized sample selection criteria. This database increases the reusability of archaeological radiocarbon data and streamlines quality control assessments for various types of paleo-demographic research. As part of an assessment of data quality, we conduct two analyses of sampling bias in the global database at multiple scales. This database is ideal for paleo-demographic research focused on dates-as-data, bayesian modeling, or summed probability distribution methodologies.
- Award ID(s):
- 1822033
- NSF-PAR ID:
- 10100551
- Date Published:
- Journal Name:
- Journal of archaeological science
- Volume:
- 101
- ISSN:
- 1095-9238
- Page Range / eLocation ID:
- 63-71
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract -
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Abstract Objectives The North American archaeological record supports a Holocene origin of Arctic Indigenous peoples. Although the Paleo‐Inuit were present for millennia, archaeological and genetic studies suggest that modern peoples descend from a second, more recent tradition known as the Neo‐Inuit. Origins of the Neo‐Inuit and their relations to the earlier and later Indigenous peoples are an area of active study. Here, we genetically analyze the maternal lineages present at Nuvuk, once the northernmost community in Alaska and located in a region identified as a possible origin point of the Neo‐Inuit Thule. The cemetery at Nuvuk contains human remains representing a nearly one thousand year uninterrupted occupation from early Thule to post‐contact Iñupiat.
Materials and methods We selected 44 individuals from Nuvuk with calibrated dates between 981 AD and 1885 AD for molecular analysis. We amplified and sequenced the hypervariable segment I of the mitogenome. We compared the Nuvuk data with previously published sequences from 68 modern and ancient communities from across Asia and North America. Phylogeographic analyses suggest possible scenarios of Holocene Arctic and sub‐Arctic population movements.
Results We successfully retrieved sequence data from 39 individuals. Haplogroup frequencies in Nuvuk were typed as 66.7% A2b1, 25.6% A2a, and 7.7% D4b1a2a1a. These results suggest that the population at Nuvuk was closest to the ancient Thule and modern Inuit of Canada, and to the Siberian Naukan people. We confirm that haplogroups A2a, A2b1, D2a, and D4b1a2a1a appear at high frequency in Arctic and sub‐Arctic populations of North America and Chukotka. Sister clades D2b and D4b1a2a1b are present in Asian and Eastern European populations.
Discussion The ancient mitochondrial sequences from Nuvuk confirm the link between the North Slope and the Thule who later spread east, and the maternal discontinuity between the Neo‐Inuit and Paleo‐Inuit. We suggest haplogroups A2a, A2b, and D4b1a2a1a are linked to the ancestors of the Thule in eastern Beringia, whereas the D2 and D4b1a2a1 clades appear to have Asian Holocene origins. Further Siberian and Alaskan genomes are necessary to clarify these population migrations beyond a simple two‐wave scenario of Neo‐Inuit and Paleo‐Inuit.
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/doi.org/10.1016/j.jas.2018.11.006
