New Discovery Defies Indian Migration Theory

A multinational group of archaeologists, headed by the curator of the prestigious Field Museum in Chicago, argues that people were already living in the Amazon rainforest 11,000 years ago when mammoth-hunting "PaleoIndians" left the oldest artifacts yet discovered in the Americas.

The curator, Anna Roosevelt, reports in an article published in Science Weekly that excavations of Caverna da Pedra Pintada, a cave on the north bank of the Amazon in Monte Alegre, Brazil, have yielded evidence of human habitation that date as far back as 11,200 years.

The evidence includes cave paintings, stone spear points, and the carbonized remains of plants and animals.

More startling to the researchers is evidence that the Amazon dwellers used an entirely different set of tools from the fluted points used by the Clovis people to hunt big game. Instead, the forest people appear to have foraged for nuts, fruits, and shellfish, and hunted large and small game.

"The evidence is that they used a totally different technology than Clovis," James Feathers, an archaeologist at the University of Washington in Seattle, said. "Technologically, the tools don't look anything like Clovis at all."

Traditionally, archeologists have theorized that the first migrants to America came across the Bering straits from Asia, settled in the North American high plains and southwest, and then moved into South America down the Andean mountain chain in search of big game which thrived in cool, dry climates.

It has been assumed that these "PaleoIndians," as they are called, first populated the Americas beginning about 11,200 years ago in a colonization process that lasted nearly 3,000 years.

But that view is challenged by the discoveries in the Amazon cave.

"We found strong evidence that a culture quite distinct from the North American PaleoIndian culture, but contemporary with it, existed more than 5,000 miles south, in this humid, tropical habitat," said Roosevelt.

Some scientists, like Feathers, who performed the dating on the cave remains, say the find suggests that the Americas were first colonized substantially before the Clovis people left their spear points behind in New Mexico. Assuming that both peoples derived from northeast Asia, it would have taken many centuries for the forest dwellers to develop such a sophisticated technology adapted to a completely different climate and ecosystem.

The plant remains from the cave include Brazil nuts, palm seeds, and fruits from a variety of other trees common in the humid tropical forests and woodlands of the Amazon. No remains of grasses or trees from more temperate habitats or grass savanna were found in the cave. Animal remains were also typical of the humid tropics.

"It seems PaleoIndians were able to adapt to a broader range of habitats than has been thought," Roosevelt said. "Amazonia, far from a dead end, fostered a dynamic culture which spanned thousands of years."

She argues that foraging bands of the kind which first used the cave, gave way to fishing villages where pottery-making developed. The pottery found in the cave and nine other nearby sites, according to the article, date back as far as 7,500 years, the earliest yet found in the Americas.

Agriculture later developed there, and the use of pottery spread as more complex societies were established -- until the European conquest.

She believes that more evidence of human culture and development may well be available at other sites in the tropical forests. The problem is that no one has yet looked hard enough, in part because conventional wisdom said the earliest settlements were most likely to be found in temperate climates.

In fact, scientists and local residents have known for a long time that the Monte Alegre caverns contained rock art and spear points, but no one had actually undertaken archaeological excavations.

"The emphasis on big-game hunting has some serious implications," she says. "For example, sociobiologists have used our supposed descent from hunters to claim a genetic basis for human behaviors such as aggression and certain gender roles, such as men bringing home the food while women are tied to domestic chores."

But these theories may result from a case of "backward extrapolation" from recent Western cultures. "If you really want to know about early cultures," she says, "you have to go back and look at (them), not just at modern people." The foraging culture of the forest dwellers suggests that women and children, as well as men, may have contributed significantly to the group's food supply.

She also says the Monte Alegre caves may have something to teach modern-day policy-makers about the interactions between human settlements and tropical forests. The finds, as well as other recent research in the Amazon, "show that so-called 'virgin' tropical forests were in fact settled and cultivated for many thousands of years."

Some of the diversity patterns found today -- such as the clustering of cashews, Brazil nuts, and certain palms -- came about precisely because prehistoric human activities altered the topography and the soil and changed the vegetation.

That means that people living in the forests on a small scale should be seen as an integral part of the ecology.

"Their continued presence on the land is critical for the survival of the habitat," she notes, adding, "It's only when outsiders subsidize exploitative activities on a large scale that we see the type of destruction that's eradicating tropical forests in some areas today."