‘Virgin’ Amazon once populated

A vast region of the Amazon forest in Brazil was home to a complex of ancient towns in which about 50,000 people lived, according to scientists assisted by satellite images of the region.

The existence of the ancient settlements in the Upper Xingu region of the Amazon in north-central Brazil means that what many experts had considered virgin tropical forests were in fact heavily affected by past human activity, the scientists reported Thursday in the journal Science.

The arrival of European colonists 500 years ago, and the diseases they brought with them, probably killed most of the inhabitants, the researchers said.

The settlements, consisting of networks of walled towns and smaller villages organized around a central plaza, are now almost entirely overgrown by the forest.