Birds “stand sentry” to help other members of their group forage for food, and
sing a special song to give warning of danger,
The research into pied babblers, a social species from the Kalahari desert of
southern Africa that lives in groups of about seven, has revealed a rare
example of apparently altruistic behaviour, in which individuals put
themselves at a temporary disadvantage for the benefit of others.
While the pied babbler community forages for food, such as small snakes and
scorpions dug up from the desert, one of them stands guard in a tree.
This sentinel goes hungry as it watches for predators, allowing its group
members to concentrate on feeding. To let other babblers know that it is on
guard, the sentry sings a “watchman’s song”, and makes alarm calls if a
predator is spotted.
While the watchman is singing, foraging individuals spread out and spend more
time searching for food than looking out for danger.
clipped from: www.timesonline.co.uk 