Richard Collins: Crows aren't fools, some make and use tools while others judge us

In the Pacific Ocean, one group of crows makes hooks from sticks to reach and rake in food

A New Caledonian crow, a type of crow that makes tools to reach food.

During an experiment three years ago, 26 dogs were shown photographs of people in various emotional states. The animals’ heart rates were measured and their responses to the pictures monitored. The results led scientists to conclude that dogs, uniquely among animals, are able to ’read’ the expressions on their owners’ faces and interpret human body language.

That dogs are capable of such responses was surprising but they, like us, are mammals. That birds might also be able ‘to think’ was deemed impossible; a mere bird could never be ‘one of us’. In recent years, however, the myth of the ‘bird-brain’ has taken a hammering.