Off the beaten track to early Amazonians.

• Author: Mackey, Chris

Dressed in a crisp business suit, Anna Roosevelt sits in her spacious third-floor office in the Field Museum, crowded by boxes of artifacts, and sips her tea.

"If I know something is correct," she says, "you could say anything to me and it wouldn't persuade me it's wrong if I see it before my very eyes. I think this rather uncooperative, assertive personality that I have has been a huge boon. On the other hand, it's stood me in good stead that I find it easy to change my mind. If I had clung to my initial ideas each time I undertook a research project, I'd have gotten nowhere. It's essential to learn from the archaeological record and let go of the ideas that don't work."

Professor of anthropology at the University of Illinois at Chicago and curator of archaeology at Chicago's Field Museum of Natural History, Roosevelt is fast becoming one of the most well-known researchers in the field of New World archaeology. After fourteen years of excavating in the lower Amazon in Brazil, she has produced evidence of a long prehistoric cultural sequence in a place scientists deemed unfit for early American civilizations. Her research and resulting conclusions are challenging long-held scientific beliefs about the early inhabitants of the Americas.

Most scientists agree that at the end of the Ice Age the first Americans, or Paleoindians, came from Asia across a now-submerged land bridge in the Bering Straits. Settling in the North American high plains, they eventually traveled south down the Andean mountain chain in pursuit of migratory game. In 1932 archaeologists discovered fluted spear points with extinct bison at Folsom, New Mexico, while similar points, dating back to between 11,200 to 10,200 years, were found at other sites. In general, the scientific world accepted these tools as the oldest human artifacts in the Americas and used this culture to develop what is now called the Clovis theory of the peopling of the Americas. Named after a site in Clovis, New Mexico, this theory purports that Paleoindians were big-game hunters, who used stone-pointed spears to kill bison and mammoth. Unable to find food in the tropical forest, they lived only in the temperate climates.

But now, by looking in places long ignored by the archaeological world, Roosevelt and a team of international researchers have documented evidence of an early society that lived deep in the Brazilian Amazon from about 11,200 to 10,000 years ago.

"The existence of a distinct cultural tradition contemporary with the Clovis tradition but more than five thousand miles to the south does not fit the notion that North American big-game hunters were the sole source of migration into South America. Clovis evidently is just one of several regional traditions," Roosevelt and her colleagues wrote in an article published in the journal Science in April 1996.

Roosevelt's theories have created a commotion in the scientific world, and like anyone going against traditional theory she has been the subject of much debate. "It's basically one group of very doctrinaire Clovis archaeologists who are still finding it very hard to accept," she says. After the publication of...