We have heard of the Indus Valley Civilisation (IVC) from the ancient Bronze Age that thrived in the northwestern regions of South Asia in the third millennium BCE.
IVC was well known for its granaries, drainage systems. some examples were systematically planned cities like Harappa and Mohenjodaro
Historians are yet to reach a consensus on many aspects of this period as its script remains undeciphered
In two new studies published in journals like 'Science' and 'Cell', a consortium of international researchers, including from India, have tried to decipher the origins of present-day Central and South Asian people
They have used recent advances made in the field of genetics and analysed genetic material (DNA) from the remains of 523 ancient populations, including people from the Indus Valley Civilisation (IVC).
The study was titled 'The formation of human populations in South and Central Asia.' In this study, researchers investigate where the people of the Indus Valley Civilisation came from, and the ancestry of the present-day Indians
People of the Indus Valley Civilisation did not descend from the early farmers of the Fertile Crescent. They still had ancestry in another Iranian-related hunter-gatherer population.
Steppe ancestry arrived in South Asia between 1900 and 1500 BCE. The present-day Indian population is a mixture of these two source populations - Ancestral South Indian (ASI) and Ancestral North Indian (ANI)
The genetical analysis throws some insights into how the Steppe pastoralists made their way into South Asia. The Steppe pastoralists were nomads from the steppes, a temperate zone stretching from modern-day Bulgaria in the west through Manchuria in the east
"We 'don't know where that population lived. It could have been in South Asia or some unsampled location in the Iranian plateau."
A majority of the ancestors of present-day South Asians are the people of the Indus Valley Civilisation
Following the decline of the IVC, around 2000 BCE, two distinct populations were formed when the Indus Valley people mixed with others
The Ancestral South Indian (ASI) population was formed by a mixture of the Indus Valley and the ancient ancestral South Indian population
Ancestral North Indian (ANI) population was formed by a mixture of Indus Valley people with the Steppe pastoralists from the Eurasian Steppes
Steppe ancestry arrived in South Asia between 1900 and 1500 BCE. The present-day Indian population is a mixture of these two source populations - Ancestral South Indian (ASI) and Ancestral North Indian (ANI)
A significant implication of the findings is the understanding of the spread of the Indo-European language family. This family includes Latin-derived languages like Spanish, Sanskrit-derived languages like Hindi and English among several others.
Researchers looked at the inheritance of the Y chromosome—a sex chromosome found only in males and passed on from father to son.
After combining the information from the Y chromosome and non-sex chromosomes, scientists found that the Steppe ancestry was introduced into South Asia predominantly by males.
Interestingly, the Steppe ancestry is very high among Brahmin and Bhumihar groups. Since Brahmins were traditional custodians of liturgy in Sanskrit, the high Steppe ancestry indicates a Bronze Age Steppe origin for South Asia's Indo-European languages
The two studies provide a reasonably precise chronology thanks to radiocarbon dating. It is a technique of determining the age of an object by looking at the radioactive carbon isotopes
One of the most definitive milestones in human history is our transition from nomadic hunter-gatherers to settled agriculturists. This change depended not only on technological advances but also on how people lived and related to each other. Farming is known to have originated in the Fertile Crescent—a semicircular region in the Middle East from the Meditteranean Sea to the Persian Gulf. Historians have long wondered how it then spread to other parts of the world. Was it through large scale human migrations, or did it develop independently?