Human migration during the prehistoric period was driven by several pressures but mainly relied on the habitability of available new land, said a Tata Institute of Fundamental Research study.
The researchers of TIFR, Mayank Vahia et al. have modelled prehistoric population dynamics using a diffusion equation with the help of numerical geological data for the Indian subcontinent taken from satellite databases.
Based on the presumption that the driving forces for people to move out of any given region depend on the neighbouring habitable regions, proximity of water and flatness and altitude of the land, they took into account the initial population first.
Then the archaeological evidence of early humans in the subcontinent helped them to trace three possible locations in Kabul which would represent the Ancestral North Indian entry into India, Hyderabad which would represent the earliest Ancestral South Indian population into India.
They have also studied two possible entry points for Ancestral Austro Asiatic which are Goa and Orissa identified as two major break points in the mountain range that mark the Indian Subcontinent for people coming to India along the coast.
“We find that people entering from Goa would soon become indistinguishable from the original Ancestral South Indian population. We therefore focus on entry from Orissa. On simulating the movement of these people we find that the groups merge in well localised geographical regions within the subcontinent,” said TIFR researchers in a research paper.
Next they analysed the genetic data of the tribal population of the region, who are largely endogamous and maintained their original genetic signal with very weak dilution due to intermixing in other rural or urban areas. “This allows us to identify the roots of different groups and compare it with our simulation,” they said.
The genetic data matched well with their predictions and helped them to expand the simulation to show that over a long period of time, the pattern of population that appears, agrees well with the present population of India.
Here is a video link [https://www.eurekalert.org/multimedia/pub/140369.php] showing the movement of people into the hinterland of the Indian subcontinent starting from Kabul to Hyderabad and North Orissa. CREDIT: Vahia, Yadav, Ladiwala, Mathur