Monkeys don't usually use stone tools in the wild, but researchers in Thailand have discovered that they can learn to, when needs must.
Until the pandemic, and the resulting lockdowns humans endured, the long-tailed macaques that live on the uninhabited Thai island of Koh Ped (south of Pattaya City) were accustomed to getting food from visitors. The creatures would actually meet tourist boats on arrival, in the expectation of being given treats. Then Covid struck, and trips to the island were banned.
When restrictions were lifted and researchers were finally able to return to the island, they were surprised to see two monkeys using pebbles to crack oyster shells - something they'd never witnessed in a decade of pre-pandemic observation.
During their next visit, they looked for the behaviour and recorded 17 instances of monkeys using stone tools, albeit clumsily: the animals would use both hands to hoist a rock to shoulder height, then throw it at the oyster bed, reports New Scientist.
This species had been thought incapable of using tools, but it seems a shortage of food motivated them to innovate; time will tell if they keep up the practice now tourists have returned, say the team from Bangkok's Chulalongkorn University.