Chimps are chumps at rock, paper, scissors
Chimpanzees are able to learn how to play rock, paper, scissors, scientists have discovered. But the animals have a crucial weakness: they struggle to grasp that scissors beat paper – so if you ever find yourself in a contest with a chimp, choosing paper every time should wrap it up.
IT’S late. You’re alone and hungry in the jungle with only a chimpanzee, one banana and your wits to get you through the night. But, fear not, scientists have found the perfect parlour game to play with a primate to win your dinner: rock, paper, scissors.
Japanese primatologists have proven that chimps understand and can play the game. However they have an Achilles’ heel. The apes take far longer to grasp that scissors can beat paper, than to understand the other winning combinations.
So selecting paper should ensure the banana is safe, even if the chimp demands a rematch.
Previously scientists have found that chimpanzees can make tools, have distinct personalities and even communicate through a rudimentary language of sounds and gestures.
But it is the first study to have shown that they are as capable of grasping the complex patterns to comprehend a game like rock, paper, scissors, which takes enhanced mental capacity. Jie Gao, the lead author, from the Primate Research Institute at Kyoto University in Japan, said: “The present study aimed to investigate whether chimpanzees could learn a transverse pattern by being trained in the rules of the ‘rock, paper, scissors’ game.
“The chimpanzees’ performance was similar to that of four-year-old children. The primary difference between the chimpanzees and children in the present study was the method of learning. Children changed their choice immediately after they made a wrong one, whereas the chimpanzees would often take multiple sessions to correct themselves.”
In the popular game the hand signal for “paper” always beats “rock”, while “rock” trumps “scissors”, and “scissors” defeats “paper”.
Seven chimpanzees of different ages and sexes living in the institute took part in the experiment. The scientists found that chimpanzees can learn the circular pattern at the heart of the game. However, it took them an average of 14 sessions to learn the third scissors-paper pair than it did the others, which they picked up in between one and three sessions.
The team then also taught the game to 38 pre-school children. They had little difficulty grasping it, and on average did so within five sessions. The research was published in Primates journal.