Stone tools offer insights into history of human evolution

Researchers suggest that hominins in India may have developed a Middle Palaeolithic culture phase around 3,85,000 years ago.

Based on the study of over 7,200 stone artefacts collected from the archaeological site at Attirampakkam in the Kortallayar river basin about 60 km from Chennai, researchers suggest that hominins in India may have developed a Middle Palaeolithic culture phase around 3,85,000 years ago and continuing up to around 1,72,000 years ago.

According to earlier evidence, the Middle Palaeolithic culture in India was dated to around 1,25,000 years ago.

The Middle Palaeolithic is an important cultural phase, associated as it is globally with both modern humans and Neanderthals or other archaic hominins, with complex histories of interaction, cultural transitions and change and dispersals.

Based on stone tool and fossil studies, the Middle Palaeolithic culture (called the Middle Stone Age in Africa) is associated with modern humans in Africa, while it is associated with both modern humans and Neanderthals in Israel. But in Europe, the Middle Palaeolithic culture is associated only with Neanderthals.

“In case of India, we cannot say who made the tools as no hominin fossil remains have been found till now. So we must be more cautious in correlating species with culture in the case of India,” says Shanti Pappu from the Sharma Centre for Heritage Education in Chennai and corresponding author of a new paper published in Nature . “The Middle Palaeolithic culture is thought to have originated in Africa. When we look at the Indian site at Attirampakkam, which is far away from Africa, we see a similar cultural change occurring. The number and nature of dispersals of populations bearing a Middle Palaeolithic culture from Africa is not a simple, linear model but is far more complex,” Prof. Pappu says.

Going deep

In 2011, Prof. Pappu and her team reported the discovery of 1.5-million-year-old stone artefacts belonging to the Lower Palaeolithic (Acheulian) culture from Attirampakkam. The objects were buried in sediments at the lowest levels in the excavation. In the top three metres of the soil, the same site has yielded artefacts that reflect a distinct Middle Palaeolithic culture.

“We see a distinct transition from the Acheulian culture to the Middle Palaeolithic culture as reflected in the artefacts at around 3,80,000 years, along with appearance of new tool types and techniques that continued here for another 2,00,000 years,” she says. During the Middle Palaeolithic, there is a distinct shift away from large flake technologies such as hand-axes and cleavers that were predominant during the Acheulian. There is a proliferation of tools made from small flakes during the Middle Palaeolithic.

“This research presents a paradigm shift in thinking about the origin and spread of Middle Palaeolithic cultures in South Asia, suggesting a far greater antiquity and more complex story than we thought. At Attirampakkam, we have a wonderful sequence contained in a single stratigraphic continuum and showing a long process of evolution,” Prof. Pappu says.