The Great DNA Hunt, Part II - Archaeology Magazine Archive


The Great DNA Hunt, Part II	Volume 49 Number 6, November/December 1996
by Tabitha Powledge and Mark Rose

Colonizing the Americas

Recent theories held that Native Americans colonized the New World in three migrations. New DNA studies suggest there was only one migration that lasted perhaps thousands of years. Key Paleoindian sites are indicated on map along with ice sheets, glaciers, and now submerged lands during the last glaciation.(Lynda D'Amico) [LARGER IMAGE, 36K]

The latest DNA investigations are challenging a widely accepted model of how the New World was colonized. While scholars agree that people entered the Americas via a land bridge linking Siberia and Alaska, there has been debate on when they crossed and whether they came at one time or in several waves. An initial consensus held that Paleoindians came to the New World about 14,000 years ago and that most Native Americans are descendants of these people, with the exception of Eskimo-Aleuts, who arrived much later. In the mid-1980s a revolutionary model claimed three distinct migrations, including the Eskimo-Aleuts, based on linguistics, dental morphology, and genetic markers such as blood types. Studies of DNA in Native American and Siberian populations in the early 1990s supported this model, but the latest DNA analyses indicate the single Paleoindian migration might be right after all.

Not all New World DNA studies focus on the colonization of the Americas. Many investigations deal with individual sites and the development of cultures in particular regions. Here the questions are about such matters as social status, diet, and gender roles.

The use of DNA analysis to answer archaeological questions is little more than a decade old, and has vast potential. Archaeology will change with the development of this new discipline. Anne Stone of Pennsylvania State University notes that DNA analysis in archaeology "is probably going to remain a small, specialized field because of the slow, frustrating, and fairly expensive nature of the work," but she adds that "ancient DNA is very exciting because we have the opportunity to address questions about human population history ranging from local questions, such as whether a group of people in a tomb are related, to larger questions, such as the history of the migration into the New World."