Unknown Middle Stone Age tech

The long-held view that a critical stone-knapping style known as Middle Palaeolithic technology was carried to Asia by early Homo sapiens when the species emerged from Africa has been dealt a severe blow.

In a paper published in the journal Nature, a team of archaeologists led by Shanti Pappu of the Sharma Centre for Heritage Education, India, report the analysis of 7000 artefacts unearthed at Attirampakkam in southern India. Collectively, the form of the stone tools and the results of dating tests indicate that the area hosted a mature Middle Palaeolithic culture from around 385,000 years ago.

Pappu and her colleagues do not suggest the Attirampakkam finds are evidence of modern human settlement. Recent analysis of a fossil found in Israel pushed the date of human migration from Africa back to about 190,000 years ago (and refocused genetic evidence that it may have occurred as far back as 270,000 years ago) but suggesting Homo sapiens reached India so early would seem a very big stretch.

It should be noted, however, that the lack of fossil evidence in India generally means that the possibility cannot be fully excluded. However, the makers of the stone tools were much more likely to be another now extinct hominin species.

Attirampakkam is a well-known fossil trove. In 2011, another team led by Pappu reported the discovery of stone tools dating back as far as 1.5 million years.

These were artefacts of what is known as Acheulian technology – big oval and pear-shaped hand-axes that have been found in many locations in the Old World and are associated with Homo erectus.

The latest trove, according to the scientists, tracks the change from Acheulian to Middle Palaeolithic technology – characterised by the creation of smaller tools and the use of a more sophisticated knapping methoid known as the Levallois technique.

The tools were found in several layers of soil. Luminescence dating narrowed the possible ages of the artefacts at the lowest (thus, oldest) layers to roughly 385,000 years ago.

In their paper, Pappu and colleagues note that “a key feature of this technology is the almost complete abandonment of Acheulian large-flake strategies”. Only a few pieces recovered, they note, indicate that Acheulian techniques persisted at all.

Tool density varies between the soil layers, but eventually drops away almost completely at around 74,000 years ago. The scientists note that the date coincides with the super-eruption of an Indonesian volcano known as Toba, which might explain the site abandonment.

Whatever the reason for the unknown community of hominins leaving Attirampakkam, however, it is the fact of their arrival that is set to shake up the prehistory of India.

“These processes … establish the presence of a fully fledged Middle Palaeolithic culture in India at around 385,000–172,000 years ago, which long pre-dates any previous evidence that suggests Middle Palaeolithic technologies were disseminated out of Africa by modern humans from around 125,000 years ago or later,” the researchers conclude.