S hards of stone produced by long-tailed macaques in Thailand’s Ao Phang-Nga National Park bear a striking resemblance to those found in some of the earliest archaeological sites in East Africa, according to researchers at the Max Planck Institute for Evolutionary Anthropology.
The monkeys use rudimentary stone tools, like a hammer and anvil, to crack open nuts. In the process, shards of stone flake off and are left behind. Although the monkeys haven’t been observed using them, the shards are similar in size and shape to those unearthed from early human settlements.
“The ability to intentionally make sharp stone flakes is seen as a crucial point in the evolution of hominins, and understanding how and when this occurred is a huge question that is typically investigated through the study of past artefacts and fossils. Our study shows that stone tool production is not unique to humans and our ancestors,” said lead researcher Dr Tomos Proffitt.
“The fact that these macaques use stone tools to process nuts is not surprising, as they also use tools to gain access to various shellfish as well. What is interesting is that, in doing so, they accidentally produce a substantial archaeological record of their own that is partly indistinguishable from some hominin artefacts.”