The Eurasian Jay, Known as the "Feathered Primate," Shows Greater Self-Control with Higher Intelligence

University of Cambridge Studies Correlation Between Bird Intelligence and Self-Control in Marshmallow Test
Eochi Exhibits Cognitive Abilities Comparable to Non-Human Primates Except Humans

'Homer', who recorded the lowest self-control in the marshmallow test for magpies. Photo by Yonhap News

[Asia Economy Reporter Bang Je-il] The bird 'Eochi' of the crow family has been found to exhibit self-control by resisting immediate temptations the smarter it is. This study is the first to confirm the correlation between bird intelligence and self-control.

According to the University of Cambridge in the UK, Dr. Alex Schnell's research team from the Department of Psychology confirmed the bird's self-control through a marshmallow test for Eochi and published their findings in the Philosophical Transactions of the Royal Society B.

The approximately 30cm-long Eochi, scientifically named Garrulus glandarius, is known to possess cognitive abilities comparable to non-human primates, second only to humans. It is sometimes called the "feathered primate."

Birds of the crow family tend to store food instead of eating it immediately, a habit believed by the research team to have driven the evolution of self-control.

To assess Eochi's self-control, the team used the marshmallow test, which typically involves children choosing between one marshmallow immediately or two after waiting for a certain period, measuring their level of self-control.

In the Eochi experiment, instead of marshmallows, insects (mealworms), cheese, and bread were presented. Mealworms are generally the Eochi's favorite food, followed by cheese and bread.

The researchers designed the experiment so that bread and cheese were immediately accessible, while mealworms were visible behind transparent acrylic but could only be accessed after a waiting period ranging from 5 seconds to 5 minutes and 30 seconds. As a result, all Eochi demonstrated self-control by refraining from eating the bread and cheese immediately and waiting to obtain the mealworms.

However, individual differences were significant. For example, an Eochi named JayLo waited the full 5 minutes and 30 seconds to get the mealworms, whereas Dolci and Homer gave in after just 20 seconds and ate the bread and cheese.

The team also conducted five cognitive tasks used to measure "general intelligence" on the Eochi subjects. Those scoring higher on these tasks tended to wait longer for the mealworm reward, suggesting a link between intelligence and self-control in Eochi, according to the researchers.

Self-control has been known to be associated with high intelligence in humans and chimpanzees, and more recently, it has been observed in cuttlefish. In March 2021, Dr. Schnell's team at the Marine Biological Laboratory (MBL) of the University of Chicago published results of a marshmallow test on cuttlefish in the Philosophical Transactions of the Royal Society B.

Similar to Eochi, cuttlefish showed self-control by waiting between 50 seconds and 2 minutes 10 seconds for a better food reward in the marshmallow test. The research team explained this is comparable to chimpanzees, crows, and parrots. Dr. Schnell stated, "Although there is individual variation in Eochi's self-control, the most interesting part is that if an individual performed well on one cognitive task, it performed well on all others, indicating that general intelligence underpins these abilities."

This content was produced with the assistance of AI translation services.