A Zoological Society of London (ZSL) study shows how a group of chimps enjoyed a game which involved moving red dice through a maze of pipes, whether they got a reward or not.
Most instances of problem solving, where animals use tools or navigate mazes, are with the object of reaching food. Hyenas, octopuses and birds such as crows all show the ability to solve problems, reported the American Journal of Primatology citing the study.
Chimpanzees have also been witnessed using tools such as a stick to forage for ants, termites and other insects or honey in hard to reach places like tree stumps, but ZSL researcher Fay Clark said they could be motivated by more than just food.
"We noticed that the chimps were keen to complete the puzzle regardless of whether or not they received a food reward. This strongly suggests they get similar feelings of satisfaction to humans who often complete brain games for a feel-good reward," added Clark.
The adult male and female chimps, who took part in the challenge daily at the Whipsnade Zoo in Bedfordshire voluntarily, were not trained on how to use the device. They had to move red dice or nuts through a network of pipes by prodding sticks through holes until they fell out into a container.
Researchers created higher "levels" of challenge by adding additional pipes and making the pipes opaque so the chimps could not see what was inside. If they completed the puzzle, they would receive the Brazil nuts or on other occasions they would get a red dice.
The apes were also given treats in separate boxes as part of the zoo's "enrichment programme", meaning the chimps could choose whether they completed the puzzle as they would receive a reward regardless.