Scientists have observed two groups of long-tailed macaque monkeys in Thailand, Southeast Asia, using stone tools differently, even though the islands they live on are less than six miles apart. Long-tailed macaques are one of only a few primate species known to use stone tools – others include humans, chimpanzees, bearded capuchin and white-faced capuchin monkeys.
The macaques use rocks that they choose carefully to hammer the shells of shellfish, such as oysters, sea snails, crabs and mussels. They crack them open and scoop out the flesh to eat.
On two neighbouring islands off the coast of Thailand, one group of macaques were seen reusing their tools, called hammerstones, whereas the monkeys on the other island threw their stones away after using them once.
A team of scientists from the…
