Kelsey Witt

KELSEY E. WITT, then a graduate student at University of Illinois, Urbana, Illinois, was awarded a grant in April 2016 to aid research on ‘Using Ancient Dog DNA to Test Models of Human Migration History,’ supervised by Dr. Ripan S. Malhi. The grantee sequenced complete mitochondrial genomes of 72 ancient dogs from 21 American archaeological sites to study the demographic history of dogs in the Americas prior to European contact, and to relate the histories of ancient dog and human populations in the Americas. Using demographic modeling, analysis found that dogs likely arrived to the Americas around 15,000 years before present (ybp), with the first peopling of the Americas. It also found that these dog mitochondrial DNA sequences split into two primary groups, with one group limited to North America and the other group distributed across North and South America. This pattern is also found in Native American populations, which derive from two genetically distinct groups. The study also found parallels in patterns of genetic diversity between ancient human and dog populations in the Americas. For example, dogs from the Midwestern United States show a rapid increase in genetic diversity around 1000 years ago, which coincides with the development of Mississippian culture, a large Native American empire centered around the Midwestern United States. This study of ancient American dogs shows their connections to the human populations who lived alongside them.