2-Apr-2009 16.00 GMT
These intelligent birds are closely related to crows and ravens. They have eyes similar to human eyes, says Auguste von Bayern, formerly of the University of Cambridge and now at the University of Oxford. "Jackdaws seem to recognise the eye's role in visual perception, or at the very least they are extremely sensitive to the way that human eyes are oriented."
When offered tasty food, hand-raised jackdaws took longer to accept it when a person' s eyes were looking towards the food than when they were looking away, say the researchers. The birds hesitated, the researchers suggest, because the person was unfamiliar and so possibly threatening.
The birds were also able to interpret human gestures to help them find hidden food. These included change of gaze and pointing. But the researchers found that the birds could not use static cues, such as eye gaze or head orientation.
Unlike most birds, jackdaws' eyes have a dark pupil surrounded by a silvery white iris. The hand-raised birds used in the study may be even better than wild jackdaws at paying attention to human gaze and responding to the gestures of the people who raised them.
The findings are particularly interesting, von Bayern says, since most other species studied so far - including our closest relative, the chimpanzee, and man's best friend, the dog - are not particularly sensitive to eye orientation or eye gaze.
Chimps and dogs seem to rely on other cues, such as head or body orientation, in figuring out the looking direction of others. They don't seem to realise that the eyes are the visual organs.
The results suggest that birds in general and the crow family in particular deserve more respect for their mental abilities.
"We may have underestimated the psychological realms of birds," von Bayern says. "Jackdaws, amongst many other birds, form pair bonds for life and need to closely coordinate and collaborate with their partner.
"This requires an efficient way of communicating and sensitivity to their partner's perspective."
The research team was led by Nathan J. Emery, of University of Cambridge and Queen Mary College, University of London. von Bayern et al.: “Report: Jackdaws Respond to Human Attentional States and Communicative Cues in Different Contexts.” Publishing in Current Biology 19, 1–5, April 14, 2009. DOI 10.1016/j.cub.2009.02.062 www.current-biology.com