"The Harvard study brings other good news for historians of ancient times. LeBlanc said the DNA captured from quids and aprons shows — in a preliminary way — that early farming populations in the Southwest descended from farmers in what is now central Mexico. That helps answer an old question among those who study the ancient Southwest: Was the idea of farming imported, or was it adopted by indigenous populations?
More broadly, archaeologists interested in migration patterns anywhere now have a new source for the DNA that can be used to track the movement of ancient people — though LeBlanc cautioned that the methods have to be retested and refined."