Homo sapiens arose in Africa at least 300,000 years ago and left to colonize the globe. Scientists think there were several dispersals from Africa, not all equally successful. Last week's report of a human jaw showed some members of our species had reached Israel by 177,000 to 194,000 years ago.
Now comes a discovery in India of stone tools, showing a style that has been associated elsewhere with our species. They were fashioned from 385,000 years ago to 172,000 years ago, showing evidence of continuity and development over that time. That starting point is a lot earlier than scientists generally think Homo sapiens left Africa.
This tool style has also been attributed to Neanderthals and possibly other species. So it's impossible to say whether the tools were made by Homo sapiens or some evolutionary cousin, say researchers who reported the finding Wednesday in the journal Nature.Nowhere is there any indication that modern humans are associated with the tools at Attirampakkam (ATM). In fact, there are no hominin remains whatsoever at ATM. The Indian subcontinent has always had a paucity of human remains, the most notable of which is the Narmada Homo erectus cranium. In Europe, the Levallois technology, which also shows up at ATM, is almost exclusively associated with Neandertals and in the Levant, at the Skhul, Qafzeh, Tabun and Amud sites in the Mt. Carmel region, it is used by both Neandertals and early moderns. Consequently, while someone was using early Middle Palaeolithic tools at ATM, we don't know who.
What is incredibly striking about the ATM site is that, from 385 ky down to 172 ky, there is continuous technological evolution, beginning with what the describers call the “terminal Acheulean,” through a punch flake industry with points, to knives. Another point made by the authors is that this Middle Palaeolithic industry appears and flourishes during a time where other sites in India are still using Acheulean technology. This suggests “that spatial variability among Palaeolithic cultural sequences is larger than previously thought.” From the Nature article1:
The behavioural transformations that mark the advent of the Indian Middle Palaeolithic at ATM are summarized by the following diagnostic features: the obsolescence of Acheulian large-flake reduction sequences, with a directional shift towards smaller tool components; the adoption and continuance of Levallois recurrent and preferential strategies; a gradual intensification of blade reduction; and an increased use of finer grained quartzite during phase II than during A gradual discontinuation of biface use—which becomes definite at ATM after approximately 172 ± 41 ka—has been reported at other Middle Palaeolithic and Middle Stone Age sites worldwide (see Supplementary Information and references therein).This is an astounding find for so many reasons. It establishes the appearance of the Levallois technology, one we know originated in Africa, outside Africa over 150 thousand years earlier than we thought. This is a technology that was considered to have originated some 400 thousand years ago. We may now have to revise this date further into the past.
It shows a clear progression of human cultural evolution, from the late Acheulean hand axes, through Middle Palaeolithic Levallois technology to a more blade-oriented technology. Sadly, it appears as though the site began to fall into disuse and the sequence stops cold around 74 kya. This is not surprising since it coincides with the Toba supervolcano eruption in Indonesia. Nonetheless, as the authors point out, it suggests multiple migrations out of Africa of first archaic Homo sapiens, then modern Homo sapiens, such as those in Misliya and that these groups interacted with the Archaic hominins they encountered along the way.
1Akhilesh, K., Pappu, S., Rajapara, H. M., Gunnell, Y., Shukla, A. D., & Singhvi, A. K. (2018). Early Middle Palaeolithic culture in India around 385–172 ka reframes Out of Africa models. Nature, 554, 97. https://doi.org/10.1038/nature25444
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