Capuchins, chimpanzees and bonobos were able to pull a piece of string after watching how it released a food reward
Monkeys are as smart as a three-year-old child when it comes to solving puzzles.
Capuchins, chimpanzees and bonobos were able to pull a piece of string after watching how it released a food reward.
Scientists said the findings showed they have the basic intelligence of a human tot as they can understand abstract properties.
Dr Amanda Seed, of the University of St Andrews, said: “We set out to find out how animals conceive the world around them. Do they have any idea that objects have abstract properties, like solidity and weight?
“Or do they rely on learning arbitrary relationships between what you see, what you do and what you get, in the same way we learn to stop at a red light?”
The research published in PLOS One involved a box containing two pieces of string, one broken and one unbroken which connected to food.
By pulling the unbroken piece the monkeys got the treat.
In one experiment the box was covered whereas in another it was open, allowing the monkeys to see that the string was connected to the food.
Both versions required avoiding the broken line and choosing the unbroken one.
In the covered version monkeys had to be shown which string to pull but when they could see the string attached the food, they could work this out unaided.
Individuals of all species performed much better in the uncovered condition as it “made sense” and they could see the string connected to the food.
The researchers said the study shows monkeys, apes and young children find it difficult to learn what to do with an object, unless they can see its functionality in action.
Added Dr Seed: “We set two tasks with the same outcome, both involved objects that could be seen, but in one the visible object caused the outcome and in the other it did not. We found the monkeys and apes were only able to solve when they could see the object’s function.
“Our research shows learning arbitrary patterns is not actually that easy for primates, and even five-year-old children find it hard.
“In comparison, choosing a connected string in a functional context is easy. This suggests these species do have object knowledge and that there is more to their world than meets the eye.”
