With our powers of reasoning, rich memories and the ability to imagine what the future might hold, human intelligence is unequalled in the animal kingdom.

Our closest relatives, chimpanzees, are adept problem solvers, making their own tools to reach food, for example. They use sophisticated gestures and facial expressions to communicate. Yet, they fall a long way short of our own ability to think and plan for the future.

Thomas Suddendorf, a psychologist at the University of Queensland, describes this as the gap – the cognitive gulf that separates us from animals.

But it was not always so wide, he says in the video above. Our species once shared the planet with other hominins with intelligence that may have rivaled our own.

Their extinction was at least partly due to the actions of our own ancestors, according to many anthropologists. We need to be careful not to make the same mistakes again and widen the gap between the species even further in our pursuit of progress, warns Suddendorf, who spoke to BBC Future at the World-Changing Ideas Summit in Sydney on 15 November.

Read more:

We’ve got human intelligence all wrong
Jason G Goldman’s column Uniquely Human, about the similarities and differences between us and the animal kingdom

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