Ready for a game? You will be shown a sequence of five different pictures. Sometimes the pictures are abstract shapes, sometimes faces. Sometimes the faces are rotated. Memorise them: you have five seconds. Go!
Now tell me what they are in the correct sequence with 20 pictures to choose from.
If your competitor was an orang-utan, it would probably beat you at this game.
'The orang-utan has such good visual memory,' says Dr Hanna Wirman, the developer of this computer game made specifically for orang-utans. They often have visual memories several times greater than humans' due to the intricate paths they have to carve out and remember in a forest of similar-looking trees.
And they will win even if the images are turned 180 degrees, because orang-utans are often upside down. 'They are sensitive at recognising images no matter how they are rotated,' Wirman said.
She created the game to highlight an area where orang-utans could beat humans: a kind of cross-species game play that, if implemented in zoos and wildlife rescue centres, could show visitors just how smart orang-utans - which share about 97 per cent of our DNA - are.