by Tony Joseph
Up against our cousins
We know from the history of early human expansion into the Levant that modern humans found it difficult to break into regions where archaic humans were already dominant. So it is reasonable to assume that when our ancestors arrived at the threshold of India, they too found themselves stymied, as in the Levant. In the paper mentioned earlier, Korisettar, Oppenheimer and Haslam suggest a new model for how modern humans may have responded to the situation, terming it the ‘Indian staged dispersal’. In broad-brush terms this means our ancestors arrived at different parts of the subcontinent at different times, and did not expand all over it in one fell sweep. They are all from the same, single OoA migration, but they may have reached different regions of India at different times, just as they reached different parts of the world at different times.
The opening assumption of the scientists is that archaic humans would have been present in far more intimidating numbers in peninsular India than in northern India. A valid observation, as evidenced by the archaeological discoveries in Attirampakkam, Hunsgi–Baichbal valley, Middle Son valley, Bhimbetka, etc., all south of the Vindhyas. So the incoming modern humans would have taken a sub-Himalayan route across the subcontinent, the scientists posit, avoiding the peninsular region, and going on to Myanmar and then south-east Asia and further on to Australia, east Asia and China. There is, of course, no reason why all the First Indians need have taken only the sub-Himalayan route. Some of them could have taken a coastal route that would have kept them out of the way of the troublesome archaic humans who were present in the central and interior parts of the peninsula. We know today that that was what happened when the first migrants arrived in the Americas – they took different routes and got separated for thousands of years. Either way, the First Indians may have managed to avoid a direct and immediate conflict with the existing robust populations of archaic humans. When we talk about migrants having taken this or that route or having gone here or there, it is not to suggest they would have en masse vacated the areas they were occupying to go and settle in new regions. It means that they and their descendants kept expanding their range into newer and newer areas, without necessarily vacating the places they were already in.
Over time, the modern humans would have expanded their footprint in the subcontinent, even moving south and displacing the archaic humans and probably driving them to extinction. The sudden appearance of Microlithic tools in the Indian archaeological record may be a clue to when and how this may have happened. Even though stone tools don’t necessarily help us identify different species of humans most of the time, microliths are a kind of exception. In India and elsewhere, they have been linked more closely with modern humans than archaic humans, and in the subcontinent we see microliths making their appearance around 45,000 years ago. Thereafter, they show a surprising level of continuity and expansion, and not just in the subcontinent. We see a similar emergence of microliths in Sri Lanka around 38,000 years ago, and they persist from then on till approximately 3000 years ago, nearabout when iron makes its presence felt, both in India and in Sri Lanka.
The earliest microliths in South Asia were found at Mehtakheri in Madhya Pradesh, dated to 45,000 years ago. Mehtakheri is one of eight sites in the Nimar region of Madhya Pradesh that had microliths ranging in age from 45,000 years to 3400 years. Curiously, the timing and location of the early finds of microliths tally quite nicely with the timing and location of an expansion (increase in population) of some First Indian lineages. According to the 2017 paper on the genetic chronology of the Indian subcontinent mentioned earlier, there was a major expansion and dispersal of mtDNA haplogroup M in central and eastern India between 45,000 and 35,000 years ago.11 Towards the end of this period is also when the climate slowly began to deteriorate as the world got closer to the full glacial conditions of MIS 2.
So there are many things happening together: the climate slowly starts getting more dry and arid, putting stress on all living populations; modern humans start relying more and more on Microlithic tools; and their population then starts expanding and spreading to new areas. The region where all of this takes place, central India, also happens to be one of the most favoured areas for archaic humans to inhabit.
Could it be that as modern humans in India found their habitats becoming drier and more arid, they responded by depending more and more on a new technology that involved making microliths and using them to create weapons like spears and arrows in order to hunt better and beat rival claimants to food and other resources? And could they have then moved into new areas that were still habitable but that they had hitherto avoided because of the presence of archaic humans there? If that is what they had indeed done, it could be said that they succeeded in all their missions, which resulted in a rapid rise in their population.
A 2009 study, ‘Population Increase and Environmental Deterioration Correspond with Microlithic Innovations in South Asia ca. 35,000 Years Ago’,12 authored by some of the biggest names in archaeology and genetics, says, ‘It has been estimated that between about 45,000 and 20,000 years ago, most of humanity lived in South Asia. This evidence is thought to reflect a population expansion in the subcontinent that is unparalleled elsewhere.’
Like the archaic humans in Attirampakkam who were at the cutting edge of technology around 385,000 years ago when they moved up to making Middle Palaeolithic tools, the modern humans of central India can lay claim to having been at the forefront of technology once again around 45,000 yeas ago, as they started making and using Microlithic tools and weapons. However, while the earliest microliths at Mehtakheri are dated to about 45,000 years ago, the technology would have arrived in different regions on the subcontinent at different periods of time. In fact, it arrives only around 35,000 years ago at critical places such as Patne in Maharashtra, Jwalapuram in Andhra Pradesh and Fa Hien and Batadombalena in Sri Lanka.
So here is a scenario that we can put together, based on what we know: around 65,000 years ago, modern humans arrive in India and are blindsided by the presence of archaic humans who have been well settled in the region for hundreds of thousands of years. They then move in a gradual and opportunistic manner, some going across sub-Himalayan northern India from the west to the east, and some taking the coastal route from the north to the south. By the time the climate reached crisis point around 35,000 years ago, modern humans had already equipped themselves with better technology to hunt down their prey and beat back their rivals. As success built on success, the rapidly growing population of modern humans started expanding their range and moving deeper into the peninsular region, thus probably forcing archaic humans to restrict themselves to local refuges – such as Jwalapuram or perhaps Bhimbetka – until they went extinct.
Jwalapuram is a good place to understand how this might have worked. Located in the Jurreru river valley of Kurnool district, its significance lies in the fact that the river basin holds layers of ash left behind by the Toba supervolcanic eruption of 74,000 years ago. When the volcano erupted in the Sumatran island, millions of tonnes of ash was dumped all over south-east Asia and south Asia, causing stress to all life in the region.
The Jwalapuram site was discovered by Professor Korisettar and was excavated a decade ago by a team of archaeologists led by him and Professor Petraglia. They found something remarkable at the bottom- most layer, under the ash: Middle Palaeolithic tools dated to around 77,000 years ago, made by who they thought were modern humans. They also found a continuation of the same tool technology above the ash layer, but dated to 45,000 to 35,000 years ago. Those findings created a stir because these frontally challenged the version that said OoA happened only around 70,000 years ago. Petraglia holds on to the theory that these tools were made by modern humans but the paper co-authored by Korisettar, Oppenheimer and Haslam in 2017 says that these products are ‘most likely the product of archaic hominins’.
More interestingly, Korisettar and Petraglia also found microliths appearing in the same Jurreru valley, starting from aroun
d 38,000 years ago and persisting until a few thousand years ago. Regarding these microliths, Korisettar, Oppenheimer and Haslam say, ‘we see the most parsimonious explanation for the Jurreru material record to be the movement of modern humans into the area 40,000 to 35,000 years ago’.
If this interpretation is correct, that the Jurreru valley was a settlement of archaic humans where Homo sapiens came around 35,000 to 40,000 years ago, then the valley could have been one of the most prominent sites in the conflict between modern humans – armed with the new technology of microliths – and their archaic cousins – still working with Middle Palaeolithic tools. Whether it was also one of the last, we will probably never know.
As you approach the wide open terrain of Jwalapuram you can see people carting away the Toba volcanic ash in sacks, to be sold as detergent or brass polish. When I visited the site in early 2018, there were trenches dug by miners, and a few metres down their walls wide bands of white ash, the remains of the mega eruption, could be clearly seen. When the volcano erupted, only about five centimetres of ash had fallen on the valley, but the band you see today is inches, not just centimetres, thick. This is because apart from the primary ash fall, the valley, for a long time afterwards, had been receiving more ash carried into it by monsoon rains, streams and the Jurreru river.
As you stand on the riverbed, it is tantalizing to try to visualize the drama that might have unfolded about 38,000 years ago on this ground, as the first modern humans of India moved into what could have been one of the last remaining refuges of archaic humans. How long did it take for the modern humans to complete the occupation of India and when did the last archaic humans on this land pass into history? Those are secrets that science is yet to unravel, but by looking at how far they were able to reach into South Asia (all the way across to south-west Sri Lanka by about 38,000 years ago) and to what extent they were able to move into the long-standing preserves of our archaic cousins (Jwalapuram by about 35,000 years ago), we can fairly assume that by around that time our ancestors were truly masters of the land they came into some 30,000 years earlier.
For a glimpse of the First Indians, look in the mirror!
This leads us to the next questions: where are their descendants today? How many are there, and where can we find them? If you want to find their closest direct descendants living today, who haven’t mixed with other populations all that much, you need to go to the Little Andaman Island and look up the Onge. There are only about a hundred of them left now, down from about 670 in 1900. Their maternal haplogroup is M and paternal haplogroup is D. They made it to the news in 2011 when a new baby was born, taking the strength of the tribe to 101.
But really, if you want to see the lineage of the First Indians, you probably only need to look into the mirror or look around in your office or home. Unlike many other regions – such as Europe, Australia or the Americas – which have seen the lineage of their original inhabitants dwindle to very low levels, the genetic lineage of the First Indians forms the foundation, the bedrock, of the Indian population today.
In fact, between half and two-thirds of our genome-wide ancestry today comes from the First Indians. This genome-wide figure, which applies to both men and women, is the most appropriate measure to grasp the genetic make-up of Indians, but there are other ways to look at it too, which provide other kinds of insights. For example, if you look at mtDNA lineages you will find that somewhere between 70 and 90 per cent of people are descendants of the First Indians, with M lineages being the most popular. If you look at Y-chromosome lineages, though, the picture is different: First Indian descendants account for only 10 to 40 per cent of the haplogroups, depending on which population group you are considering. (This massive difference between the male and female lines of descent encapsulates the history of later migrations, which we will tackle in chapter 4.)
At this point you could refer back to pp. 19–26 that dealt with mtDNA and Y-chromosome lineages, or here is a brief summary. MtDNA is transferred from mother to daughter in an unbroken chain, while Y-chromosome is transferred from father to son similarly. So when we say that somewhere between 70 and 90 per cent of mtDNA lineages derive their origin from the First Indians, it means that in the case of 70 to 90 per cent of Indian women, if you traced their maternal line back through the ages, you will arrive at a woman who was an original OoA migrant and reached India some 65,000 years ago. Similarly, when we say that 10 to 40 per cent of Y-chromosome lineages are of First Indian descent, it means that in the case of 10 to 40 per cent of all Indian men, if you traced their paternal line back through the ages, you will arrive at a man who was an original OoA migrant.
A woman belonging to the Bonda tribe in Koraput, Odisha. The Bonda speak Remo, an Austroasiatic language.
A woman belonging to the Gond tribe in Bastar, Chhattisgarh. The Gond speak Gondi, a Dravidian language.
So here is a question: if you were to identify a single person who embodies us Indians the best, who do you think it should be? Ideally, it should be a tribal woman because she is most likely to be carrying the deepest-rooted and widest-spread mtDNA lineage in India today, M2. In a genetic sense, she would represent all of our history, with very little left out. She shares the most with the largest number of Indians, no matter where in the social ladder they stand, what language they speak and which region they inhabit because we are all migrants, and we are all mixed. And she was here from the beginning. And she was most likely also at Mohenjo-daro as the ‘dancing girl’ (the image on the cover) about 4500 years ago, during the period that most shaped us as we are today.
But before we get to the urban civilization of Mohenjo-daro, Harappa, Dholavira, Rakhigarhi and the other cities and towns in the valleys of the Indus and Ghaggar–Hakra twin river systems, we need to know how we became farmers from hunter-gatherers, over what period of time and why.
1This is a hypothetical scenario. Recent research suggests the impact of the volcanic eruption on life in the region was not as severe as earlier understood.
2Not all archaeologists agree with this distinction, though. ‘This idea of successful and failed dispersal is also under scrutiny,’ says the archaeologist Ravi Korisettar, adding, ‘All dispersal events are successful.’
3According to the National Human Genome Research Institute, ‘A chromosome is the structure housing DNA in a cell . . . DNA is a remarkably simple structure. It’s a polymer of four bases – A, C, T, and G – but it allows enormous complexity to be encoded by the pattern of those bases, one after another.’ Pieces of DNA, or strings of code, that lead to observable traits such as height or eye colour are called genes.
4This is a reference to the fact that the Y-chromosome and mtDNA are haploid – inherited from a single parent, without mixing with the DNA of the other parent. This is unlike the rest of the chromosomes, which are diploid, or inherited from both the parents.
5There is low frequency presence of N and M in Africa today, but this is usually attributed to back-migration from Eurasia after the OoA event.
6Until about two million years ago, there was no Red Sea and animals could just walk across from Africa into Asia, or from Asia into Africa, all along the region that is today separated by the Red Sea. It is likely that Homo erectus was one of the last mammals to walk across from Africa to Asia through this route. The Red Sea was formed by the Red Sea Rift, caused by the divergence between the African plate and the Arabian plate. The rift started about two million years ago, and since then Africa has been moving away from Arabia at the rate of fifteen millimetres every year. It still continues to widen.
7Why is it not possible that Homo sapiens migrated to the Levant, say, around 60,000 years ago and mingled with Neanderthals, resulting in our current gene mix? The sequence of evidence of modern human occupation of the world does not support this. The earliest evidence for modern humans in Europe is around 45,000 years ago while they were in Australia at least by around 60,000 years ago. This suggests that the OoA migration happened through the Southern Rout
e, reaching first Arabia, then south Asia, south-east Asia and Australia. If the peopling of the world had happened through the Northern Route, one would expect to see evidence of modern human presence in Europe much earlier than in east Asia or Australia.
8The crucial assumption here is that the migrants are beachcombers, surviving mainly by their skills in using marine resources. Is this a realistic assumption? Archaeology says it’s possible. From around 125,000 years ago in Africa, we begin to see evidence of modern humans being beachcombers, surviving by catching fish and shells. The proof is usually easy to spot: piles and piles of split shells (called shell middens). The earliest evidence of shell middens comes from the Abdur site on the Eritrean coast, just across the Red Sea from the Arabian peninsula. The site also yielded remains of large mammals, suggesting that though these modern humans were into seafood, they were not exclusively so. There have been other early finds of shell middens in Africa – such as from the Klasies river mouth in South Africa. But the Abdur find caused a frisson of excitement because it was so close to the Southern Route.
Modern humans, usually terrestrial hunter-gatherers, may have turned to marine resources during one of the glacial periods, when aridity and cold turned large parts of Africa into deserts. But sea levels would have been much lower during these cold periods than they are now, and most of the sites with evidence of their coastal settlements would now be underwater.
9Ravi Korisettar, et al., ‘Out of Africa, into South Asia: A Review of Archaeological and Genetic Evidence for the Dispersal of Homo sapiens into the Indian Subcontinent’, in Beyond Stones and More Stones, Ravi Korisettar, ed. (The Mythic Society, 2017).