At www.newscientist.com/article/dn24082-early-south-americans-conquered-the… … it is assumed the Atacama desert was a barrier to human settlement but excavations of a site on a low hill surrounded by arid valleys has altered that perception. The archaeologists dug up stone tools, animal bones, sea shells, and the remains of a fireplace, some 85km from the coast. It is now thought the desert was not so harsh in the early Holocene. They found evidence of marshland – as in wet and boggy. The view now is that there were oases in the desert that have since dried out.