The findings suggest humans left Africa to arrive in South Asia around 55,000 to 60,000 years ago - long after the Mount Toba supereruption 74,000 years ago.
This contradicts some archaeologists' claims that modern humans have been living in the region for twice that long.
The research used a combination of archaeological and genetic data to suggest the new earliest possible date for the exodus from Africa to Asia, 'LiveScience' reported.
"Modern humans weren't there when that happened. They arrived afterwards," Richards said.
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Most archaeologists believed humans migrated to what is now India between 50,000 and 60,000 years ago. However, in a 2007 study, archaeologists reported on stone tools unearthed in Jwalapuram in southeastern India both above and beneath the ash layer deposited by the Mount Toba supereruption about 74,000 years ago.
That mega eruption spewed enough lava to create two Mount Everests and blocked sunlight for years.
To test the idea that humans reached South Asia before the eruption, Richards and his colleagues analysed 817 samples of mitochondrial DNA, which is carried in the cytoplasm of the egg and is only passed on through the maternal line, from people throughout the subcontinent.
They then compared it with existing samples from East Asia, the Near East and sub-Saharan Africa.
These ancient humans appear to have colonised the coasts of the subcontinent first, and then spread into the interiors along rivers, Richards told the website.
In a separate research, archaeologist Paul Mellars of the University of Cambridge in the UK and his colleagues analysed the stone tools in Jwalapuram and compared them with stone artifacts from both other regions in the subcontinent and Africa.
The team concluded that the tools from before the eruption did not resemble those used in Africa during the same period and, therefore, weren't made by modern humans. Instead, archaic humans - possibly Neanderthals - probably made the tools, Mellars told the website.