From Apes to Humans:
Earliest diversion of humans from apes occurred 5000000 years ago[ 5 million] in Africa and dispersed out of Africa. They belong to the genus Homo.
Who belongs to the genus Homo?
Anthropologists say that Africa is the source of earliest Manu as per Rig Veda. Anthropologists call any species in genus Homo as human and interbreeding between Homo species has occurred through time.
Migration of genus Homo:
Earliest human migrations, of Homo erectus, out of Arica, appeared 2000000 years ago [2 million], and they may have lived till as recently as 108000 years ago [Solo man, in Java]. They may have arrived in India 1.5 million years ago, no fossil has been found to date, just tools.
The pre- archaic humans were followed by the migration of archaic humans, Homo heidelbergensis, 500000 years ago [1.5 million yrs later] or did archaic humans evolve in from H erectus simultaneously in different parts of the world? H heidelbergensis fossils have been found in Africa, Europe and Asia. It is proposed that they gave rise to Homo sapiens, Neanderthals and Denisovans. These interbred with H erectus and each other, and of Neanderthals and Denisovans, it is the Denisovans lived in Asia.
So did Denisovans live in India? No fossils have been found in India, yet. What has been determined is that their DNA makes 5% of the genetic constitution people of Australia and South Asia. Analysis of the amount of Denisovan ancestry found that Indians have the largest admixture after the people in Australia. Among the Indians, the largest were among people in the Himalayan region and South and Central India.
Anatomically modern humans, Homo sapiens, diverged 300000 years ago, and migrated out of Africa, there were at least 2-3 such migrations of Homo sapiens with genetic impact.
An evolved H erectus or H heidelbergensis or H sapiens, fossilized skull, now called Narmada man, was found in India, in 1982, dated back to 300000-150000 years ago. Fossils found in Asia may change the history of evolution of humans.
Waves of pre archaic humans, Homo erectus, were followed by Homo heidelbergensis, and thereafter came Homo sapiens [ there might be others in between but this is how far the paleontologists have come with all the bones they have excavated as of now].
And an earlier Northern route, as early as 210000 years ago, through Egypt, Israel, Middle East and Palestine. They may have reached China 100000 years ago but went extinct and did not make an impact on current genetic make up.
A later Southern route was 13000 to 70000 years ago, out of Horn of Africa through strait of Bab el- Mandeb, landing in Yemen, travelling through U.A.E. , Oman and India.
If you are wondering how did the early humans cross the strait to go from Eritrea and Djibouti, so was I. It seems 50000 years ago, this strait was 70 meters shallower, and not the current 12 miles wide and there may have been islands in the strait that could be reached with simple rafts.
A third migration was through Levant 40000 years ago.
The anatomically modern humans interbred with local archaic humans to give rise to local contemporary humans.
A lot of this story of migration is in an ever changing landscape as paleontologists discover more.
Coming back to India and keeping in mind the multiple migrations from Africa, where does the Indus Valley civilization fit? Why the focus on it? What happened between 1 million years ago and 7000BCE in India?
Homo sapiens arrived in India 120000 to 75000 years ago. They were hunter- gatherers or South Asian Andamanese Hunter gatherer related hunter gatherer or Ancient Ancestral South Indians ( The Andamese hunter gatherer crossed over by a land bridge [since non existent] 25000 years ago, after the last glacial maximum). It is hard to imagine having ancestors who were hunter gatherers, especially considering we are Jains.
The AASI were followed by Ancient Iranian people 12000 years ago, 2000 years before agriculture developed in Iran/ Persia, is different then the DNA of people of Fertile crescent who developed agriculture in 9500 BCE.
The AASI and AIP groups interbred and gave rise to the people of Indus Valley Civilization, so called due to discovery of this civilization in modern day Pakistan on the Indus river by the British in 1920, who ruled the region at that time. We know this now due to the DNA results from Rakhigarhi, India, also, part of Indus valley civilization. Most importantly, the Rakhigarhi DNA shows that there was no Aryan gene or R1a1 gene of Eurasians from the Steppes as previously believed.
Why is absence of Eurasian R1a1 gene in IVC population important?
The Indus Valley civilization is the earliest known civilization in India. It existed since 7000 BCE. It developed before appearance of nomadic men of Steppes arrived on horses in India. Drought in 2000 BCE -1500 BCE caused a decline and movement South and interbreed with the AASI again to form the Ancestral South Indian.
A highlights of recent study of the genome of Indus Valley resident, verbatim, suggests:
- The individual was part of a population that is the largest source of S.A. ancestry
- .Iranian related ancestry split from Iranian plateau lineage >12000 years ago
- First farmers of Fertile Crescent contributed little or no ancestry to the later S.A.
So when did the Eurasians arrive?
The Aryan migration did happen, just later in time frame from what was previously believed. In 2000BCE -1500 BCE, Eurasians or Aryans from Steppes arrived in India on horseback with / out the Proto Indo European language. They interbred with the people of IVC and are the current Ancestral North Indian.
And in last 4000 years, ASI interbred with ANI, to result in the modern Indian people who are a mixture of South Asian Hunter Gatherer, Iranian Hunter Gatherer, and Steppes Eurasians.
In more recent history, many other arrived in India, mstly, as an invasion, namely, the Greek, the Persians, the Moghuls and lastly the Europeans invasion.
It is with these parting thoughts, I leave you to ponder on the legacy we give the future generation of world children.
Share what you think, I would love to hear from you.