Like humans and monkeys, crows also wait before making a decision

Melbourne, Sept 14 (ANI): Humans and monkeys are not the only ones who would wait for better rewards. A new study has shown that crows and raven birds also wait before making a decision.

In the experiments, the researchers found that the birds waited up to five minutes to swap food for better rewards.

"The results are surprising because we knew that the birds would probably be able to wait for few seconds, but not for so long and not in such a flexible manner," ABC Science quoted lead author Dr Valerie Dufour, researcher in ethology and cognition at Universite de Strasbourg, as saying.

"Some waited for minutes, which is comparable to what monkeys did," she added.

In humans, deferred gratification has been linked to academic achievement.

In the current experiment, the researchers trained 12 birds to swap tokens for food.

They then gave each bird a piece of food, and kept their giving hand closed while showing an exchange reward in the other hand. After the waiting period finished, they opened the giving hand. If the bird returned the initial piece of food, it received the reward in exchange.

Rewards ranged in quality, and birds exchanged more often for high quality foods. The maximum waiting period was five minutes.

During the wait, some birds put the original item on the ground or hid it in a cache, checking on it regularly.

"The birds who succeeded at the longest delay all used these distractive tactics while waiting," said Dufour.

"Controlling their impulse to eat certainly appeared costly for them," she added.

The study appears in the current issue of journal Royal Society Biology Letters. (ANI)