Ancient Indian roots?

摘要

A study published in the February issue of The American Journal of Human Genetics (Sengupta et al 2006) provides the most thorough investigation to date of the genetic origins of the Indian people. It suggests that the origins are largely indigenous, dating back to the Palaeolithic period, and that the genetic influence of the Indo-European-speakers who established the caste system was small. How have they come to these conclusions? We humans seem to have an insatiable curiosity about our origins. Surprisingly, perhaps, we know quite a lot about the distant past: populations all over the world originated in Africa, with those outside Africa being largely if not entirely derived from the exodus of a small number of Africans around 50,000-60,000 years ago (Jobling et al 2004). We also know a lot about the last few centuries from historical records. But we know much less about the period in between. And a lot happened: the climate fluctuated enormously, including a glacial maximum ("ice age") around 20,000 years ago, while after ～ 10,000 years ago the way of life of most people changed from obtaining their food by hunting and gathering to producing it by growing crops or herding animals. Historical records from the last few thousand years document migrations, wars and plagues.