Alex Kacelnik and colleagues at the University of Oxford set a number of cockatoos a challenge: pick a lock to access a nut visible behind a transparent door. The birds had to remove a pin, followed by a screw and a bolt, before turning a wheel to release a latch (see video).

Five birds were successful after some guidance, or with practice, but one of the cockatoos – called Pipin – broke in unassisted in under 2 hours. It was also the only bird to remove the screw with its foot instead of its beak.

"Some birds excel at different tasks," says Kacelnik. "Pipin is an ace at solving locks whereas another bird at the lab is good at making tools."