Birds understand people's eyes

People are not the only animals that know how to use their eyes in communication. A recent study showed that gray crow crows could understand our eyes.

A crow crowed gray.Photo: zeebyrd.com.

Scientists have long wanted to know if there are any other animals besides humans who can use eye contact to exchange information.

Many previous studies have shown that some animals that are considered smart - like chimpanzees and dogs - cannot understand the eyes of their fellow humans.

Like humans, the gray crow crow's eyes are very visible from afar, with white irises surrounding the pupils.

The similarity of eye structure between humans and gray crow crow makes the biologists of Oxford University (UK) think that the gray crow crow can understand our eyes. They conducted an experiment to prove this claim.

'If the gray crow reads the eyes of humans, they can also read the eyes of their fellow humans,' said Auguste von Bayern, the research leader.

Von Bayern experimented with gray crow crowds during his doctoral dissertation at Cambridge University (England). In one experiment, Von Bayern measured the time that a crow crowed gray to get food in a tray. Her two associates, including one the bird was familiar with, stood near the food tray so that the crow could see.

The results show that when seeing 'strangers', the bird will take longer to get food. However, when the "acquaintance" looks sideways or closes the eyes, the crow also appears hesitant.

This suggests that the gray crow crows assess the level of risk through the movement of the human eye and not any other signs.

In the second test, Von Bayern hid food in many places to find a pack of gray crow. One of her colleagues looked at each position in turn to hide food. The team found that the crows found food after watching the partner's gaze.

Experts in Von Bayern's group said they will continue to conduct some more tests to see if the gray crow knows the eyes of humans through the natural instincts or human nurturing process.