For a long time, modern people viewed their gathering and hunting ancestors as primitive and impoverished, barely eking out a living from the land. In more recent decades, anthropologists studying contemporary Paleolithic societies — those that survived into the twentieth century — began to paint a different picture. They noted that gathering and hunting people frequently worked fewer hours to meet their material needs than did people in agricultural or industrial societies and so had more leisure time. One scholar referred to them as “the original affluent society,” not because they had so much but because they wanted or needed so little.8 Nonetheless, life expectancy was low, probably little more than thirty-five years on average. Life in the wild was surely dangerous, and dependency on the vagaries of nature rendered it insecure as well.

But Paleolithic people also acted to alter the natural environment substantially. The use of deliberately set fires to encourage the growth of particular plants certainly changed the landscape and in Australia led to the proliferation of fire-resistant eucalyptus trees at the expense of other plant species. In many ecosystems, especially small ones like Pacific islands, the arrival of humans resulted in the rapid extinction of some native plants and animals. Other hominid, or human-like, species, such as the Neanderthals in Europe or “Flores man,” discovered in 2003 in Indonesia, also perished after living side by side with Homo sapiens for millennia. Whether their disappearance occurred through massacre, interbreeding, peaceful competition, or something unrelated to the human presence, ultimately they did not survive the rise of humankind. Thus the biological environment inhabited by gathering and hunting peoples was not wholly natural but was shaped in part by their own hands.