The Hindu published a serialised review of a book Who We Are and How We Got Here (2018) by David Reich, a scholar of genetics and Professor at the School of Medicine at Harvard University. It consists a range of facts and ideas and has serious implications for the history of India. It has privileged the south over the north against the leftist historiography, used for representing Indian history and the revisionist-nationalist historiography. The work suggests the need for a paradigm shift in the approach. For the last thirty years, intellectuals have witnessed a raging conflict of views on history, particularly the origin of Sanskrit language and the people who used it.
At the very start of his book, the Reich presents his stand on Hitler’s notion of a ‘superior race’ and the contempt for other races resulting out of it. This is really an important starting point for a professor of genetics, which may lead to genocide, if it is used partially.
According to the author, there were no humans in Eurasia two million years ago. The term ‘Homo’ arose in the paleo-anthropological record in Africa and spread out of Africa into Eurasia two million years ago with the first known skeletal remains and archaeological sites in the Caucasus, in Indonesia. Thereafter, it spread to other places throughout Eurasia, including India.
However, the ancestors of modern humans in India only spread there after 50,000 years ago. Later, there is evidence for a large-scale spread of anatomically modern peoples whose elements look like ours again out of Africa. These people displaced the previous set of humans throughout Eurasia, Europe, East Asia, South Asia, and elsewhere in Eurasia. These modern people had skeletons like ours. This modern occupation of Eurasia began in earnest, after about 50,000 years ago. There is no information about where modern humans arrived first and via which route.
In the Andaman Islands, people who seem to be relatively unmixed descendants of some of the first people in different parts of Eurasia such as in Australia and New Guinea. However, it is not clear whether there has been continuous occupation of the Andaman Islands since then, or if they are very early habitants of these islands. Most probably, they lived in South-East Asia or the South Asian mainland. It is not clear where is the mainland though; but it might not be the Indian subcontinent itself; rather parts of Indonesia like Sumatra or Myanmar.
As per the author, South Asia is one of the most diverse places on earth, with many hundreds of languages, great human diversity, and great genetic diversity as well. The great majority of groups in India speak Indo-European and Dravidian languages. These are the two largest language families in India, and which are genetically well described as being arrayed on a gradient of different proportions of ancestry and inheritance, two very different ancestral populations, different from each other like Europeans and East Asians.
There is limited information about the deep past. There is no rich source of information deeper in time from writing. Mythology may be one, which got passed down, or the languages people speak, as they are related to each other. There are linkages between the languages that are spoken in different parts of the world. The fact that people share languages is often a clue that there is some movement of people. Besides, another evidence is the archaeological findings. Now, we can get a human skeleton and connect and obtain DNA from it, which became possible in the past 10 years. Archaeologists have thoroughly studied and characterised and understood the culture associated with them. It has been learnt from the genetic data that it is almost never the case that in any place today, people are directly descended without mixture, without external input, from the same people who live there 10,000 years ago. For example, the people in Britain today inherit almost no ancestry from the people who lived in Britain 10,000 years ago.
On the basis of genetics, the colour of the eyes and the darkness of the skin of people who lived 10,000 years ago can be predicted. They probably had blue eyes, very dark skin almost as dark as people from sub-Saharan Africa. But about 6,000 years ago in Britain, there was a large-scale movement of people bringing farming from the continent. The people who live in any one place today inherit some unbroken ancestry, sometimes probably more than in the case of Britain. However, most of the ancestry of any person does not come from people who live within the same 500 kilometre or even 1,000-km radius, where they now live. The population collision and mixture occurred after the end or during or after the end of the Harappan Civilisation, a little bit after 4,000 years ago.
Science is an attempt to get at truth, but how the truth is used or misused is terribly important. What genetic analysis of Indian population history has shown is an alternation between periods of genetic isolation and periods of mixture. In South Asia, there is an alternation of periods of mixing of groups and periods of isolation, which happened over a long time. Every few hundred years, or maybe every thousand or two thousand years, groups form and mingle with other groups in a very dramatic way. That mixed population developed its own kind of endogamy with limited influx until the next big mixing event occurred.
In India, there is a lot of mixing across jati lines. Often, it is the case that people have alliances with people often from ‘lower’ caste, lower social status jati groups that get incorporated into their group. In this case also, the same degree of impact of the ancestors of the original group cannot be seen.
That any one group is pure is genetically wrong. Many stories about the past have been falsified by genetic data. The science does not really have a moral aspect; it is just what it is. It is an uncontrollable force, which explodes mythology, prejudicial understanding, and the narratives of isolation on a very large timescale.
In India, as elsewhere in the world, there is precious little information about the time before the emergence of writing, and even from the time after writing. That’s why many people did not have their stories handed down. Therefore, every type of information is required, be that mythology, musicology, studies of languages and similarities of words and shared words that are unique to those regions, phonetics, studies of the ancient building tools, crops and foods that people ate and left behind. Thus, some meaningful information can be obtained.
A lot of further progress has been made in understanding the history of South Asian populations. Now, there is a clearer sense of the ancestry of at least some people who were part of the Indus Valley Civilisation. Based on DNA from just one individual from the Harappan site, called Rakhigarhi in Harayana, and from over a dozen other individuals living in South Asia itself, almost certainly immigrants from the Harappan Civilisation and are living in the area with Turkmenistan to the north and Iran to the west, it can be said that these people were outliers in their communities. Genetically, they were different from the other primary groups, and were genetically more Iranian; and they have a mixture related to present-day south Indians.
The formation of present-day South Asian population genetically arose after the decline of the Harappan Civilisation. Genetically, the mixture included people more from the south, similar to the Andamanese and population in South-East Asia, and to some of the ancestry in Austro-Asiatic speakers, like Khasi. They also mixed with people to the north, who have ancestry related to the south. The mixture of these people, documented through ancient DNA, forms one of the ancestral populations of India. People from the south form the later ancestral populations. But most of the ancestry of both of the groups comes from the Harappan gradient. So, the Harappan-related ancestry is actually the single largest source population for almost all Indians.
Where that ancestral group was distributed is not known. But wide disruptions associated with dramatic cultural changes are documented in archaeological record, including the disruption of Harappan Civilisation. These disruptions are linked with movements of people and with a mixture both of the south and the north. Further movements of these groups formed the gradient of today by about 2,000 years ago.
Centre for Cellular and Molecular Biology (CCMB), Hyderabad runs a large-scale programme by the Indian government that involves many students, usually masters students who do collections in diverse villages throughout India, trying to catalogue ethnic diversity inside the Indian subcontinent. Today, there are around 18,000 or so samples from something like 500 groups. There is a minimum of 4,500 documented ethnic groups in India. There are some 10 times more unsampled groups than sampled ones, depending on how they are counted. And this is, in the end, only a fraction, maybe 10 per cent of the diversity in India.
Courtesy: frontline