Friday, July 27, 2007

Modern Humans Lived in India Earlier Than Thought, Study Finds



Modern Humans Lived in India Earlier Than Thought, Study Finds

By Chris Dolmetsch

July 5 (Bloomberg) -- Remains of stone tools found amid ash deposits in India from a volcanic eruption 74,000 years ago show that modern humans were living there earlier than scientists had previously thought, according to a study to be published in tomorrow's edition of the journal Science.
The Youngest Toba Tuff eruption in Indonesia, the largest volcanic event of the past 2 million years, blanketed an area from the South China Sea to the Arabian Sea with ash. Scientists had theorized that the blast produced a ``volcanic winter'' that lowered global temperatures, killing plants and animals and keeping humans from leaving Africa more than 60,000 years ago.
Study author Michael Petraglia, a University of Cambridge lecturer, and colleagues found tool fragments from soil both above and below a deposit of Toba Tuff ash, showing that humans were already in India at the time and survived the blast.
``This is some of the earliest evidence for the spread of modern humans out of Africa towards Australia,'' Petraglia said in a telephone interview from New York.
Petraglia and colleagues including Ravi Korisettar of Karnatak University in Dharwad, India, found 215 artifacts under a 2.55-meter (8.4-foot) thick ash deposit near Jwalapuram, in the Jurreru River valley of southern India, and 276 more relics above the layer.
Limestone, Quartzite Fragments
The study says the relics, made of limestone, quartzite, chert and other minerals, are likely from a variety of stone tools from the Indian Middle Paleolithic era that lasted from about 150,000 to 38,000 B.C.
Yet the characteristics of the artifacts are more typical of the African Middle Stone Age that ended about 40,000 years ago than they are of younger artifacts found elsewhere in Europe and Asia, the study says. That finding suggests that modern humans had migrated out of Africa and were already in southern India when the Toba Tuff eruption blanketed the region in ash.
``It will be very much debated,'' Petraglia said. ``There are people that are wedded to their theories and won't like it at all, and there are others who will welcome our study because this part of the world is very understudied.''
The research was funded by the Swindon, U.K.-based Natural Environment Research Council and its Arts and Humanities Research Council Oxford Radiocarbon Accelerator Dating Service, the Berkeley, California-based Leakey Foundation, the McDonald Institute for Archaeological Research, the Australian Research Council and Queens College in Cambridge.

To contact the reporter on this story: Chris Dolmetsch in New York at cdolmetsch@bloomberg.net .
Last Updated: July 5, 2007 14:00 EDT

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