Why Did Early Humans Leave Africa Without the Latest Gadgets
Posted: Fri Sep 02, 2011 12:59 pm
http://news.sciencemag.org/sciencenow/2 ... tml?ref=hp
On the northwest shoreline of Kenya's Lake Turkana, at a site known as Kokiselei, researchers previously found both Oldowan and Acheulian tool types in the same 1.76-million-year-old sediments. The tools were located in a series of gravel, sand, and mudstone beds and included picklike tools, basic hand axes, and broken pieces of stone left behind in the tool-making process. (Just who made the tools is unclear from the archaeological evidence alone, though our relative Homo erectus is identified as the likely creator of at least the Acheulian tools.) The new research pins down a new geological date for the site.
The date pushes back the origin of the Acheulian culture by almost 200,000 years, the team reports online today in Nature. And that means that advanced hand axes had already been invented when humans first started leaving Africa, says the study's lead author, geologist Christopher Lepre of the Lamont-Doherty Earth Observatory in Palisades, New York.