A research group led by Associate Professor Toshiki Suzuki of the University of Tokyo has discovered that the great tit, a type of wild bird, uses wing movements as gestures to convey specific messages.
Until now, research on gestures in wild animals has mostly consisted of observational reports on the movements of the limbs of great apes (chimpanzees, bonobos, gorillas, etc.). Animals other than apes are known to move their arms, wings, and other parts of the body, but it was largely unclear whether these gestures conveyed messages.
From May to June 2023, we set up nest boxes in a forest in Kitasaku District, Nagano Prefecture, and observed eight breeding pairs of great tits. Great tits are monogamous birds, and once the eggs hatch, the male and female work together to feed the chicks. The entrances to tree cavities (holes in trees) and nest boxes are small, and two birds cannot enter at once. During this time, I discovered that they use gestures to determine the order in which they enter the hive.
When two great tits, a male and a female, come near the nest box at the same time with food in their mouths, one of them wags its wings back and forth. Then, I realized that the other bird was going to enter the nest box first. It is usually the female that flaps her wings, and the male enters the nest box first. On the other hand, if the female does not flutter her wings, she enters the nest box first.
The time it took for the male to enter the nest box was shorter when the female waved her wings than when she did not. When the parents came to feed alone, no wing-waving behavior was observed.
This research revealed that bird wings have a communication function called ``gesture'' in addition to ``flying.'' It is hoped that research into gestures and their meanings will become more active in a variety of animal species in the future.
Paper information:【Current Biology】The 'after you' gesture in a bird
