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http://www.siliconindia.com/shownewsdata.asp?newsno=28104
India first stop in humans long march
Friday, May 13, 2005
NEW DELHI: In a discovery that could help rewrite the history of human evolution, scientists from Hyderabad have come up with startling evidence that India could very well have been the first stop in the long march from Africa. And that this journey happened through sea rather than land as is now widely believed
While scientists from the Center for Cellular and Molecular Biology (CCMB) tracked this migration using modern molecular biological tools, vital clues came from an interesting sourcethe Onge and Great Andamanese tribes of Andamans, the Indian Express newspaper reported.
Reporting their work in todays issue of the prestigious American journal Science, the scientistsin association with an Estonian teamwere able to reconstruct this prehistoric story of human colonization by comparing DNA collected from living humans.
Hunting for long-forgotten signs that erase fast when populations intermix, the seven-member CCMB teamled by Lalji Singh and Kumaraswamy Thangarajzeroed in on the Onge and Great Andamanese who have been living largely in isolation.
Since no fossil records are available, the team used a novel approach of studying the latent molecular clock that is embedded in DNA. They recorded the tell-tale signs of this migration by way of unique mutations in DNA found in the powerhouse of cells called mitochondria, the report said.
Using blood samples, they compared the complete sequence of the mitochondrial DNA extracted from five members each of the Onge and Great Andamanese, all part of the negrito group of inhabitants of the islands.
To their surprise, the team found that the Onge and Great Andamanese resembled the African population more closely than East Asians or even the mainland Indian population of today.
This, according to them, could have happened only if the Onge and Great Andamanese were almost direct descendants of the first human beings believed to have been born in Africa 150,000 years ago, the report added.
The CCMB findings suggest that when humans started migrating, one group used the coastal route to reach the Andamans and continued to survive in pure populationsall intervening signatures have been erased by time.
Lalji Singh says this migration through the sea may have happened some 65,000-70,000 years ago and predates the land journey by about 10,000 years. In effect, the new evidence makes these two tribes possibly the oldest surviving human stock in Asia.
Lalji Singh calls them, Immensely unique and very precious for humanity.
The danger, of course, is that rapid modernisation is eroding the native lifestyle of these primordial tribes. Today, the numbers of Great Andamanese on Strait Island have fallen to a dismal 20 and Onge to 98.
Singh calls these islands, The last Eden degrading fast.
India first stop in humans long march
Friday, May 13, 2005
NEW DELHI: In a discovery that could help rewrite the history of human evolution, scientists from Hyderabad have come up with startling evidence that India could very well have been the first stop in the long march from Africa. And that this journey happened through sea rather than land as is now widely believed
While scientists from the Center for Cellular and Molecular Biology (CCMB) tracked this migration using modern molecular biological tools, vital clues came from an interesting sourcethe Onge and Great Andamanese tribes of Andamans, the Indian Express newspaper reported.
Reporting their work in todays issue of the prestigious American journal Science, the scientistsin association with an Estonian teamwere able to reconstruct this prehistoric story of human colonization by comparing DNA collected from living humans.
Hunting for long-forgotten signs that erase fast when populations intermix, the seven-member CCMB teamled by Lalji Singh and Kumaraswamy Thangarajzeroed in on the Onge and Great Andamanese who have been living largely in isolation.
Since no fossil records are available, the team used a novel approach of studying the latent molecular clock that is embedded in DNA. They recorded the tell-tale signs of this migration by way of unique mutations in DNA found in the powerhouse of cells called mitochondria, the report said.
Using blood samples, they compared the complete sequence of the mitochondrial DNA extracted from five members each of the Onge and Great Andamanese, all part of the negrito group of inhabitants of the islands.
To their surprise, the team found that the Onge and Great Andamanese resembled the African population more closely than East Asians or even the mainland Indian population of today.
This, according to them, could have happened only if the Onge and Great Andamanese were almost direct descendants of the first human beings believed to have been born in Africa 150,000 years ago, the report added.
The CCMB findings suggest that when humans started migrating, one group used the coastal route to reach the Andamans and continued to survive in pure populationsall intervening signatures have been erased by time.
Lalji Singh says this migration through the sea may have happened some 65,000-70,000 years ago and predates the land journey by about 10,000 years. In effect, the new evidence makes these two tribes possibly the oldest surviving human stock in Asia.
Lalji Singh calls them, Immensely unique and very precious for humanity.
The danger, of course, is that rapid modernisation is eroding the native lifestyle of these primordial tribes. Today, the numbers of Great Andamanese on Strait Island have fallen to a dismal 20 and Onge to 98.
Singh calls these islands, The last Eden degrading fast.