London (PTI): A landmark research has shown that birds respond to a human's gaze, allowing them to pick up on very subtle signals and use them to their advantage.

In humans it is well-known that the eyes are said to be the 'window to the soul', conveying much about a person's emotions and intentions.

A group of researchers at the University of Bristol in Britain set up experiments that showed starlings will keep away from their food dish if a human is looking at it.

However, if the person is just as close, but their eyes are turned away, the birds resumed feeding earlier and consumed more food overall.

The research, published online in the April edition of Proceedings of the Royal Society B, describes the first explicit demonstration of a bird responding to a live predator's eye-gaze direction.

"This is a great example of how animals can pick up on very subtle signals and use them to their own advantage," said Julia Carter, a PhD student at Bristol.

Carter argued that a predator's head orientation and eye-gaze direction are more subtle indicators of risk, and useful since many predators orient their head and eyes towards their prey as they attack.

"By responding to these subtle eye-gaze cues, starlings would gain a competitive advantage over individuals that are not so observant. This work highlights the importance of considering even very subtle signals that might be used in an animal's decision-making process," Carter was quoted as saying in the report by the Science daily online on Tuesday.

However, researchers cautioned that further studies would be needed to answer definitely whether birds understand that a human is looking at them, and that they might pose some risk.