[ Back to EurekAlert! ] Public release date: 6-Dec-2011
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Proceedings of the National Academy of Sciences

European colonization and Native American populations

A genetic study suggests that indigenous Americans experienced a significant contraction in population size some 500 years ago, coincident with European colonization. Brendan O'Fallon and Lars Fehren-Schmitz analyzed ancient and contemporary mitochondrial DNA to construct a demographic history of indigenous Americans. While archeological and historical records indicate that European contact resulted in widespread Native American mortality from various sources including warfare, enslavement, and disease, genetic studies had so far found little evidence of a recent decrease in Native American population size. The authors studied a large genetic dataset and identified several distinct demographic epochs, with a rapid expansion of Native American populations roughly 8,000-12,000 years ago followed by a long period of demographic stability. About 500 years ago, the indigenous American population decreased substantially, with the number of females reduced to about 50% of the pre-decline peak nearly 5,000 years ago. The population size remained low for several hundred years after the recent decline, though it eventually returned to levels similar to those before the event, the authors report. The results are consistent with historical records indicating that European colonization reduced the size of indigenous American populations, and the scale of the estimated contraction suggests that this decrease was not localized to particular regions or communities, according to the authors.

Article #11-12563: "Native Americans experienced a strong population bottleneck coincident with European contact," by Brendan O'Fallon and Lars Fehren-Schmitz
MEDIA CONTACT: Brendan O'Fallon, University of Washington, Seattle, WA; tel: 801-556-8527 (day), 801-556-8527 (evening); e-mail: brendano@u.washington.edu

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