- Ancient hunter-gatherers from Sri Lanka’s western rainforests used a quartz-containing “flexible toolkit” to hunt small mammals, new research shows.
- The researchers discovered South Asia’s oldest recorded, human-made hunting tools in Fa-Hien Lena Cave, an ancient rock shelter in a patch of lowland rainforest on the Indian Ocean island.
- While similar tools have been used in Europe and Africa, the hunters’ targets in those locations had been large- or medium-size animals, not primates or giant squirrels, as in Sri Lanka.
Some 45,000 years ago, hunter-gatherers in the rainforests of Sri Lanka hunted down small tree-dwelling animals like monkeys and giant squirrels using small stone tools called microliths, a new study shows.
These hunters are the oldest recorded users of human-made hunting tools in all of South Asia, according to the research paper published Oct. 2 in PLOS ONE.
A team of researchers from the Max Planck Institute for the Science of Human History in Germany have unearthed how efficient hunting strategies were used by these rainforest dwellers, allowing them to adapt to their environment.
Microliths are small tools that were shaped by flaking away bits of the face of a piece of stone — what scientists call “retouching.” They are recognized as efficient hunting implements or parts of projectile weapons, and in the capable hands of Sri Lanka’s rainforest hunters, they were used to kill primates for food.
Similar tools have been used in Africa and Europe. But in these places, they were used exclusively to kill large- or medium-size animals in savannas and woodlands, but never monkeys, according to the paper.
These environments were once thought to pose significant barriers to human foragers, impeding their movement and thermoregulation. Also, these locations had few carbohydrate-rich plants and fat- and protein-rich animals.
A quartz toolkit for hunting
Fa-Hien Lena Cave in western Sri Lanka is the island’s largest cave and among Asia’s largest rock formations. From the depths of this cave, which is surrounded by tropical evergreen rainforest, evidence has now emerged showing the wide use of different ecosystems by humans, indicating how their adaptability helped populations spread.
The new research builds on an earlier multidisciplinary analysis of the Fa Hien Lena Cave and offers the first detailed analysis of lithic technology from the cave site based on excavations conducted in 2009, 2010 and 2012.
The paper identifies lithic technology — the production of usable tools using various types of stones — within as an indicator of a successful, stable technological adaptation to the tropics and highlights how these microliths were an important part of what allowed Homo sapiens to colonize a diversity of ecological settings during its expansion within and beyond Africa.
In the past 10 years, increasing archaeological as well as pre-historic evidence had shown the use of tropical rainforest resources by Homo sapiens at several locations in South Asia and Southeast Asia tens of thousands of years ago.
But archaeological evidence of regular exploitation of tropical rainforests indicates the role played by environment in human adaptation.
Preliminary studies of collections of lithic tools within the cave totaled 9,216 artefacts, many of which were made from quartz from river pebbles.
Sri Lanka has also emerged as a particularly important area in which unique prehistoric hunter-gatherer adaptations and technological strategies used in tropical rainforest ecosystems developed.
The earliest human fossils of South Asia were found in Sri Lanka’s caves and rock shelters dating from 45,000-36,000 years, with archaeological analyses of ancient plants and animals showing the reliance on rainforest resources for their survival, between 36,000-3,000 years.
“What is less clear, however, is the range of technological strategies that these populations used to enable their dedicated rainforest subsistence practices, and how adaptations may have varied through time,” the authors write.
Wedage, O., Picin, A., Blinkhorn, J., Douka, K., Deraniyagala, S., Kourampas, N., … Roberts, P. (2019). Microliths in the South Asian rainforest ~45-4 ka: New insights from Fa-Hien Lena Cave, Sri Lanka. PLOS ONE, 14(10), e0222606. doi:10.1371/journal.pone.0222606
Banner image of the ancient Fa Hien Lena Cave surrounded by a lush patch of rainforest in western Sri Lanka, courtesy of Max Planck Institute, Germany.