Michael Haslam
A CASHEW is a tough nut to crack. You must carefully balance it on an anvil and bash it with a hammer, while avoiding contact with the caustic resin in its shell. This takes great skill. Yet bearded capuchin monkeys living in north-east Brazil take it in their stride. And their tool-wielding talents don’t end there. They also dig for tubers and insects with rocks. Females sometimes even hurl them at males in what appears to be an unusual flirting tactic. We used to think that using tools was the preserve of our hominin linage and one of the remarkable talents that made us human. So much for that idea…
In fact, we have known for some years that our closest living relatives, chimps, employ a variety of tools, including some made of stone. Recently, primatologists have