Ancient DNA Study Reveals Dispersal Patterns and Diversity Changes in North American Deer Species
Researchers analyzed ancient, historical, and modern DNA from five North American cervid species (caribou, moose, wapiti, white-tailed deer, and mule deer) to trace their evolutionary history over two million years. The study found rapid expansion of moose and wapiti after arriving on the continent, with wapiti subsequently losing genetic diversity, and identified shared ancestry between eastern and western Canadian caribou populations separated by 30,000 years. The findings demonstrate how glacial cycles, migrations, and human colonization shaped the genomic diversity of North American wildlife.
A bioRxiv preprint describes a comprehensive ancient DNA analysis of five extant North American cervid species, examining specimens spanning from 30,000 years ago to the present. The research reveals distinct demographic patterns: moose and wapiti showed rapid population expansion following their arrival in North America, though wapiti subsequently experienced a loss of genetic diversity. The study also identified genetic connections between caribou populations in eastern and western Canada, with a 30,000-year-old western Canadian sample sharing ancestry with modern eastern Canadian caribou. Additionally, the analysis uncovered rapid diversification within the Odocoileus genus (white-tailed and mule deer), resulting in incomplete lineage sorting and mito-nuclear discordance—a pattern indicating complex evolutionary relationships. The researchers emphasize the value of chronological DNA sampling in understanding how external pressures, including glacial cycles and human colonization, drive genomic changes in wildlife populations.
What's missing
The study's limitations regarding sample size, geographic coverage, and temporal resolution across different species are not detailed in the abstract. Additionally, the specific mechanisms driving the loss of wapiti diversity and the implications for current conservation efforts are not elaborated.
What different sources said
- bioRxivCenter
Ancient DNA perspectives on North American cervids identify dispersal waves and fluctuations in diversity
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