Once there was a long list of cognitive attributes thought to be uniquely human: they included language, morality, solving problems by inventing tools, projecting our thoughts into the past or the future, and a ‘theory of mind’ – the ability to attribute desires, knowledge and other mental states onto others, realising that these may be different to our own. Over the past few decades, the edifice of human cognitive uniqueness has slowly been chipped away as first great apes and then other species, including elephants and dolphins, have passed landmark tests of cognitive skill. At the same time, the gap between these ‘clever’ species and those that perch far away from us on the tree of life has arguably already been closed.

People are animals, too | Mosaic.