New study refutes claims of early humans in India prior to Mount Toba eruption

Jun 11, 2013 by Bob Yirka report
Graphic by Dora Kemp. (c)2013 PNAS, doi: 10.1073/pnas.1306043110

(Phys.org) —A team of British researchers has published a paper in Proceedings of the National Academy of Sciences refuting claims made by a research team in 2007 suggesting that humans migrated to India as early as 75,000 years ago. In their paper, they say mtDNA and new archeological evidence indicates that modern humans arrived in India approximately 50 to 55 thousand years ago.

For many years scientists believed modern humans had migrated from Africa to India approximately 50,000 to 60,000 years ago. Then in 2007, a team of archeologists discovered some that had apparently been made by modern in a site in , which appeared to have been from a much earlier time. The team reported finding such tools both above and below the ash line caused by the massive eruption of Mount Toba approximately 74,000 years ago. The explosion from the volcano is believed to have sent so much ash into the air that the planet was cooled for several years thereafter.

In this new effort, the researchers sought to settle the arguments about the Indian migration timeline once and for all. To do so, they collected mitochondrial from 817 volunteers all across the Eurasian subcontinent, while also reexamining the stone tools that had originally set off the debate.

In studying the mtDNA, the researchers concluded that modern humans had settled in the area no earlier than 55,000 to 60,000 years ago. The evidence indicated that had settled along the coast first, then traveled inland following rivers. Such a timeline indicates that modern humans didn't migrate to India till well after the eruption of Mount Toba.

Meanwhile, others on the team investigating the stone tools discovered by the earlier team found that they were very likely the work of Neanderthals, not early modern humans. They note that the author of the original study claiming the stones had been made by early humans had withdrawn the paper with the suggestion that the tools were likely made by an unidentified group of archaic people living in the area at the time.

Taken together, the team says their findings should once and for all end the debate regarding the migration timeline for modern humans moving into India.

Explore further: Oldest DNA ever found sheds light on humans' global trek

More information: Genetic and archaeological perspectives on the initial modern human colonization of southern Asia, PNAS, Published online before print June 10, 2013, doi: 10.1073/pnas.1306043110

Abstract
It has been argued recently that the initial dispersal of anatomically modern humans from Africa to southern Asia occurred before the volcanic "supereruption" of the Mount Toba volcano (Sumatra) at ∼74,000 y before present (B.P.)—possibly as early as 120,000 y B.P. We show here that this "pre-Toba" dispersal model is in serious conflict with both the most recent genetic evidence from both Africa and Asia and the archaeological evidence from South Asian sites. We present an alternative model based on a combination of genetic analyses and recent archaeological evidence from South Asia and Africa. These data support a coastally oriented dispersal of modern humans from eastern Africa to southern Asia ∼60–50 thousand years ago (ka). This was associated with distinctively African microlithic and "backed-segment" technologies analogous to the African "Howiesons Poort" and related technologies, together with a range of distinctively "modern" cultural and symbolic features (highly shaped bone tools, personal ornaments, abstract artistic motifs, microblade technology, etc.), similar to those that accompanied the replacement of "archaic" Neanderthal by anatomically modern human populations in other regions of western Eurasia at a broadly similar date.

Press release

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plaasjaapie
1 / 5 (7) Jun 11, 2013
Very nice example about how a strong scientific paradigm like the "out of Africa" scenario simply dismisses contrary evidence. This is right out of T S Kuhn's playbook in the Structure of Scientific Revolutions.
arq
4 / 5 (1) Jun 11, 2013
The findings should be independently verified by another team!
k_m
1.2 / 5 (5) Jun 11, 2013
The findings should be independently verified by another team!

Existence should be independently verified.
Bog_Mire
not rated yet Jun 11, 2013
I truly believe you exist.
Shootist
1 / 5 (5) Jun 11, 2013
I bloody well know I exist. The rest of you are a bit of bad bacon.
Torbjorn_Larsson_OM
5 / 5 (4) Jun 12, 2013
@plasjaapie: How so? OOA is considered the dominant flow, even in today's reticulated models. So it tested correct.

Speaking of testing, Kuhn's philosophical ideas are untestable, so why would they interest anyone outside of the magical thinking of philosophy? Eg, define "scientific revolution" or his "paradigm" in a testable way!
JVK
1 / 5 (4) Jun 12, 2013
Evidence that a change in a single base pair led to a single amino acid substitution that enabled the nutrient-dependent thermodynamically-controlled adaptive evolution of organism-level thermoregulation associated with pheromone-controlled reproduction in a human population in what is now central China appears to refute the out of Africa migration theory. Were the Neanderthals replaced by anatomically modern human populations during the ~30,000 years it took for the human population to arise? I ask because the molecular mechanisms of nutrient-dependent pheromone-controlled adaptive evolution appear to be conserved in species from microbes to man. Thus, it would be unusual if the Neanderthal - Modern human transition was not associated with climate change and de novo production of starch molecules in the leaves of plants ingested by... nevermind. I think I lost you in your untestable theories.
Shitead
3.7 / 5 (6) Jun 12, 2013
The study defies logic; it basically says that since modern-day inhabitants of India came from post-Toba migrations, no pre-Toba people lived in India. This conclusion does not follow from the premise. The correct conclusion would be that if pre-Toba populations lived in India, they did not survive to pass down their mDNA. A great many local human populations throughout the Old World "ceased to be" in the aftermath of the Toba eruption, but they did exist.