Evrim Yazgin
Cosmos science journalist
Scientists are revealing new details at a cave site in northeastern Laos which contains some of the earliest evidence of Homo sapiens in mainland Southeast Asia.
Tam Pà Ling cave has been studied for the past 14 years. Human fossils were deposited at the site 86,000–30,000 years ago. At the time, Homo sapiens wasn’t the only human species around in Asia. Both Denisovans and Homo floresiensis – sometimes referred to as the ‘Hobbit’ – were both present.
A new study published in the Quaternary Science Reviews has subjected the dirt dug from the cave to high-precision tests to find out what the environment was like tens of thousands of years ago.
“Using a technique known as microstratigraphy at the Flinders Microarchaeology Laboratory, we were able to reconstruct the cave conditions in the past and identify traces of human activities in and around Tam Pà Ling,” says first author Vito Hernandez, a PhD candidate at Flinders University in Adelaide, Australia.
Microstratigraphy allowed the researchers to study the dirt in the tiniest detail, observing structures and features that preserve information about past environments. They were even able to find traces of animal and human activity which otherwise might have been overlooked during the excavation process.
They reconstructed ground conditions in the cave between 52,000 and 10,000 years ago.
Analysis of the soil revealed the cave’s interior changed dramatically. It fluctuated from a temperate climate which was frequently wet, to one which was seasonally dry.
“How early Homo sapiens came to be buried deep within the cave has long been debated,” says Mike Morley, an associate professor at Flinders University.
“Our sediment analysis indicates that the fossils were washed into the cave as loose sediments and debris accumulating over time, likely carried by water from surrounding hillsides during periods of heavy rainfall.”
Micro-traces of charcoal also suggest that the team found evidence of either forest fires in the region, or that ancient humans visiting the cave may have used fire in the cave or near its entrance.
