Shortly after the macaques had filled their bellies with seafood and vacated the area, the team then dug into the ground, looking for these tell-tale signs of tool use. Identifying a range of stone tools, they excavated them. Radiocarbon dating of the nearby oyster shell debris found the tools to be around 10 to 50 years old, which at the very least shows that macaques have used tools here for half a century.
“Uncovering the history of the macaques' foraging behavior is a first step,” Haslam added. “As we build up a fuller picture of their evolutionary history, we will start to identify the similarities and differences in human behavior and that of other primates.”
Tool use was once thought to make humans unique, but it’s now abundantly clear that this is no longer the case. These macaques are one of the most prolific groups of tool users known to science, and their oyster-prizing, nut-smashing activity has been documented in incredible detail for some time, but they are far from alone in their ingenuity.
Macaques often search for the best stones to use for different tasks. University of Oxford via YouTube
Chimpanzees can fashion hunting spears out of branches, bonobos can fish for termites using sticks and reeds, and orangutans use sticks, leaves, and rocks of various sizes to aid in eating difficult-to-reach food. Even non-primates can use tools: Birds belonging to the Corvidae family regularly fashion tools out of sticks, octopuses make shields out of shells, and elephants can make sure water reserves don’t leak out of a tree by plugging the gap with plants, mud, and sand.