First off, the first paragraph is nothing short of idiotic. There is absolutely no evidence whatsoever that Homo erectus went extinct because they were lazy. They colonized huge sections of Asia and were integral to the appearance of early modern humans in the area.They might have disappeared from this particular area of Saudi Arabia but that is all. Also from PhysOrg:
"At the site we looked at there was a big rocky outcrop of quality stone just a short distance away up a small hill.Maybe this particular population was stressed in some way. Maybe the tools that they made were good enough to get done what they needed. Who knows. It is a huge inference, though, that because they didn't use the raw materials that were better that they were “lazy.” The last sentence of the abstract reads thus:
"But rather than walk up the hill they would just use whatever bits had rolled down and were lying at the bottom.
"When we looked at the rocky outcrop there were no signs of any activity, no artefacts and no quarrying of the stone.
"They knew it was there, but because they had enough adequate resources they seem to have thought, 'why bother?'".
This is in contrast to the stone tool makers of later periods, including early Homo sapiens and Neanderthals, who were climbing mountains to find good quality stone and transporting it over long distances.
The Acheulean hominins at Dawadmi were strong and skilful, with their adaptation evidently successful for some time. However, these biface-makers were also technologically conservative, and used least-effort strategies of resource procurement and tool transport. Ultimately, central Arabia was depopulated, likely in the face of environmental deterioration in the form of increasing aridity.This sentence alone belies the opening, “lazy” paragraph of the PhysOrg story. More junk journalism.