"Archaeologists who study early hunter-gatherer societies are discovering that even the simplest cultures altered their environments, whether they meant to or not.
For example, aboriginal people in Australia burned huge areas to change the landscape so they could hunt animals more easily. Perhaps the most famous example is the way mastodons and giant sloth and other ice-age animals were killed off by roving bands of hungry humans.
Torben Rick, an archaeologist at the Smithsonian Institution in Washington, says the notion of hunter-gatherers living in perfect harmony with their environment is going the way of the dodo. He says he's discovered that indigenous people even altered America's coastlines, thousands of years ago."