BIRDS may be capable of deliberately deceiving one another, an ability till now mainly associated with primates.
Thomas Bugnyar and Kurt Kotrschal at the Konrad Lorenz Research Station in Gr眉nau, Austria, wanted to study how ravens (Corvus corax) learn about finding food from each other. They trained four adolescent captive-bred ravens to take the lids off small containers to get at cubes of cheese inside. The researchers then put the cheese in containers of a certain colour, while leaving containers of another colour empty. The birds 鈥� two male and two female 鈥� were then left to figure out which contained the food.
One raven, a subordinate male named Hugin, was particularly adept. In the first 18 days, he was first to find the treat-filled containers 82 per cent of the time. However, as soon as he found it, the other male, Munin, came over, chased him away and snatched whatever food remained.
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But Hugin came up with a way to deceive his rival. After finding a container with food and being approached by Munin, he set off to a bunch of empty containers and hung about prying lids off empties until, inevitably, Munin came over for a look. At this point, Hugin raced back to the correctly coloured containers and gobbled up what he could.
This is the first case of a bird actively misleading a member of its own species, the researchers say in Animal Cognition (vol 7, p 69).