Genetic Discontinuity between the Maritime Archaic and Beothuk Populations in Newfoundland, Canada

Authors: Ana T. Duggan, Alison J.T. Harris, Stephanie Marciniak, Ingeborg Marshall, Melanie Kuch, Andrew Kitchen, Gabriel Renaud, John Southon, Ben Fuller, Janet Young, Stuart Fiedel, G. Brian Golding, Vaughan Grimes, Hendrik Poinar

Curr. Biol., Vol. 27, Oct. 2017, DOI: http://dx.doi.org/10.1016/j.cub.2017.08.053

Abstract

Situated at the furthest northeastern edge of Canada, the island of Newfoundland (approximately 110,000 km^2) and Labrador (approximately 295,000 km^2) today constitute a province characterized by abundant natural resources but low population density. Both landmasses were covered by the Laurentide ice sheet during the Last Glacial Maximum (18,000 years before present [YBP]); after the glacier retreated, ice patches remained on the island until ca. 9,000 calibrated (cal) YBP. Nevertheless, indigenous peoples, whose ancestors had trekked some 5,000 km from the west coast, arrived approximately 10,000 cal YBP in Labrador and ca. 6,000 cal YBP in Newfoundland. Differential features in material culture indicate at least three settlement episodes by distinct cultural groups, including the Maritime Archaic, Palaeoeskimo, and Beothuk. Newfoundland has remained home to indigenous peoples until present day with only one apparent hiatus (3,400–2,800 YBP). This record suggests abandonment, severe constriction, or local extinction followed by subsequent immigrations from single or multiple source populations, but the specific dynamics and the cultural and biological relationships, if any, among these successive peoples remain enigmatic. By examining the mitochondrial genome diversity and isotopic ratios of 74 ancient remains in conjunction with the archaeological record, we have provided definitive evidence for the genetic discontinuity between the maternal lineages of these populations. This northeastern margin of North America appears to have been populated multiple times by distinct groups that did not share a recent common ancestry, but rather one much deeper in time at the entry point into the continent.

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A molecular portrait of maternal sepsis from Byzantine Troy

Authors: Alison M Devault, Tatum D Mortimer, Andrew Kitchen, Henrike Kiesewetter, Jacob M Enk, G Brian Golding, John Southon, Melanie Kuch, Ana T Duggan, William Aylward, Shea N Gardner, Jonathan E Allen, Andrew M King, Gerard Wright, Makoto Kuroda, Kengo Kato, Derek EG Briggs, Gino Fornaciari, Edward C Holmes, Hendrik N Poinar, Caitlin S Pepperell.

eLife 2017;6:e20983; doi: http://dx.doi.org/10.7554/eLife.20983

Abstract

Pregnancy complications are poorly represented in the archeological record, despite their importance in contemporary and ancient societies. While excavating a Byzantine cemetery in Troy, we discovered calcified abscesses among a woman’s remains. Scanning electron microscopy of the tissue revealed ‘ghost cells’, resulting from dystrophic calcification, which preserved ancient maternal, fetal and bacterial DNA of a severe infection, likely chorioamnionitis. Gardnerella vaginalis and Staphylococcus saprophyticus dominated the abscesses. Phylogenomic analyses of ancient, historical, and contemporary data showed that G. vaginalis Troy fell within contemporary genetic diversity, whereas S. saprophyticus Troy belongs to a lineage that does not appear to be commonly associated with human disease today. We speculate that the ecology of S. saprophyticus infection may have differed in the ancient world as a result of close contacts between humans and domesticated animals. These results highlight the complex and dynamic interactions with our microbial milieu that underlie severe maternal infections.

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