A study from the University of Cambridge has shown that Jays will turn down the opportunity of an instant reward to get a better one later on.
Individuals performing more strongly in a series of five cognitive tests were better able to resist the immediately available treat in anticipation of the better offer, suggesting these individuals were more intelligent. This relationship between intelligence and self-control has been demonstrated in chimpanzees and cuttlefish, but it is the first time it has been seen in birds.
Jays which performed better in cognitive tests were more patient (Clive Daelman).
The researchers presented 10 Jays with a series of drawers with visible contents, marked with different symbols. The Jays learned how the each symbol related to whether the food in each drawer was available immediately, after a delay, or not at all. They also learned that once a drawer had been opened, other possibilities were removed.
Once the preferences of each bird were identified, the authors investigated how long each bird would wait for a worm from the ‘delay’ drawer instead of taking the less tempting offers of bread or cheese from the ‘immediate’ drawer.
They found that all birds resisted the immediate food for a better offer, although how long each bird was prepared to wait varied, and an increased delay tested their patience. Some couldn’t wait any longer than 20 seconds but others resisted temptation for five-and-a-half minutes. None of the birds bothered to wait when the worm was presented in the ‘unavailable’ drawer.
Dr Alex Schnell, lead author of the study published in Philosophical Transactions of Royal Society B, said: “Our research provides further evidence that self-control plays a key ingredient in what it means to be intelligent.”
The least patient birds resisted the immediately available food for 20 seconds, but others waited more than five minutes (Clive Daelman).
Dr Manon Schweinfurth, an expert in animal behaviour at the University of St Andrews, said: “This suggests that self-control and cognition is linked. Indeed, the same link has been found in children, too.”
However, research suggesting children who are more patient in the marshmallow test, where two sweets are made available if a child can resist one, go on to have better lives, have been called into question by recent studies.
Pigeons are among the other birds which have shown self-control in similiar research, but the relationship between intelligence and impulse control revealed by this study breaks new ground.
Reference
Schnell, A K, Boeckle, M, and Clayton, N S. 2022. Waiting for a better possibility: delay of gratification in corvids and its relationship to other cognitive capacities. Philosophical Transactions of the Royal Society B. DOI: https://doi.org/10.1098/rstb.2021.0348
