The Stone Age might conjure up images of early humans, sitting around a campfire or hunting prehistoric beasts, but evidence shows that we’re not the only species that has learned how to work with stone tools.
Wild chimpanzees (Pan troglodytes) use stone tools to crack open nuts. They place the nut on a flattened rock (known as an anvil) and strike it with a second stone (known as a hammer). Evidence from Côte d’Ivoire in Africa shows that chimpanzees have been using this technique for more than 4,000 years. This suggests that stone tool use might be a trait that both humans and chimpanzees inherited from their last common ancestor. Although, it’s also possible that both species learned this skill independently of each other.
The hammer-anvil technique is also used by several species of primate, including capuchins (Sapajus libidinosus) in Brazil and long-tailed macaques (Macaca fascicularis) in Thailand. In the case of capuchins, the stone hammers can weigh up to 1kg (2.2lbs) – one-quarter of their body weight – and it can take them up to eight years to master the skill. Archaeological evidence shows that capuchins have been using nut-cracking stones for at least 3,000 years.