Founding Families

摘要

A geneticist armed with computer simulations of prehistoric populations says that only about 200 to 300 people crossed the ice age land bridge from Asia to become the founding population of North America. Of that pioneering group, there were just 70 adults of reproductive age, contends Jody Hey of Rutgers University in Piscataway, N. J. Hey arrived at that strikingly small number after analyzing DNA from living Asians and Native Americans. Using nine specific DNA sequences as reference points, he inferred the movements and characteristics of the ancient population, including the Americas' founding fathers and mothers.