Ancient history: A Russian scientist works at Con Moong Cave. Russian experts have joined excavations at several caves since 2010 in an attempt to complete a dossier promoting UNESCO recognition of the area. — Photo courtesy Viet Nam Archaeology Institute

THANH HOA (VNS)— Findings from two recent excavations in central Thanh Hoa Province show the development of stone tools by early cave dwellers and their adaptation to climate change, according to scientists.

The excavations were completed last month by scientists from the Viet Nam Archaeology Institute and the Russian Academy of Science at Con Moong and Diem caves in Thach Thanh District.

"We found many animal bones, [snail, crab] shells and quartz-stone working tools in a 14 square metre excavation pit at Con Moong Cave," Professor Nguyen Khac Su, a member of the excavation team, told Viet Nam News. "The 10 different layers of soil down to 9.5 metres in depth contain traces of early humans who lived between 60,000 and 7,000 years ago. This is one of the most intact and thickest continuously settled soil structure found at any site in Southeast Asia."

Su said that sandwiched in the layers, fragments of bones and shells indicated changes in global climate and the adaptation of techniques for shaping stone tools. In some layers there were remains of animals that lived in hot weather and in other layers, there were traces of animals that lived in cold weather. There were also shells and bones that had shown adaptation to changing weather patterns.

In layers reflecting the different climatical ages, the stone tools were found to also have changed, reflecting human adaptation. As time went by, they tended to be more well-polished, flatter and made of less common types of stone, such as quartz.

Su said archaeologists had found a human skeleton buried in a bent, sitting position with a hand covering the folded knees and a hand on cheek, one of the earliest ways of burying bodies. The posture is also that of a baby in its mother's womb. It is also similar to the way that some ancient Aboriginal people were buried in Australia..

At nearby Diem Cave, archaeologists uncovered burial sites, animal bones, stone tools and even primitive pottery objects. The cave is believed to have been the home of people of a different culture, because the bodies were interred in different ways.

At Con Moong Cave, human habitation was discovered in 1974, but extensive excavations did not begin until 1976. Since 2008, Vietnamese scientists began serious research at the site.

Russian experts joined the excavations at Con Moong and neighbouring caves in 2010 to compile a dossier that would encourage UNESCO to recognise the area as a World Cultural Heritage site. The joint-project will end next year. — VNS