The Hindu, March 2015 where the title is “Humans adapted to living in rainforests much earlier”
An analysis of teeth dating back up to 20,000 years in Sri Lanka has suggested that humans adapted to living in rainforests much earlier than thought. The researchers from Oxford University, working with a team from Sri Lanka and the University of Bradford, analysed the carbon and oxygen isotopes in the teeth of 26 individuals, with the oldest dating back 20,000 years.
They found that nearly all the teeth analysed suggested a diet largely sourced from the rainforest. The study, published in the journal Science shows that early modern humans adapted to living in the rainforest for long periods. Previously it was thought that humans did not occupy tropical forests for any length of time until 12,000 years after that date, and that the tropical forests were largely ‘pristine’, human—free environments until the Early Holocene, 8,000 years ago.
Scholars reasoned that compared with more open landscapes, humans might have found rainforests too difficult to navigate, with less available food to hunt or catch. “This is the first time scientists have investigated ancient human fossils in a tropical forest context to see how our earliest ancestors survived in such a habitat,” co—author Professor Julia Lee—Thorp from Oxford University said.
The researchers studied the fossilised teeth of 26 humans of a range of dates. All of the teeth were excavated from three archaeological sites in Sri Lanka, which are today surrounded by either dense rainforest or more open terrain.
The analysis of the teeth showed that all of the humans had a diet sourced from slightly open ‘intermediate rainforest’ environments.
Only two of them showed a recognisable signature of a diet found in open grassland. However, these two teeth were dated to around 3,000 years, the start of the Iron Age, when agriculture developed in the region. — PTI
File:PRIMITIVE MAN HUNTING ANIMALS at the Museum of Vietnamese History.JPG –Pic from commons.wikimedia.org
ALSO SEE “Genomes link aboriginal Australians to Indians,” by Ed Yong in Nature 14 January 2013, http://www.nature.com/news/genomes-link-aboriginal-australians-to-indians-1.12219