Drongos borrow other species’ warning sounds and freshen up their fraud
Courtesy of T. Flower
Real-life masters of the art of false alarms don’t keep crying wolf. Shrieking multiple fake danger signals lets a bird keep its scams going.
When food gets scarce, African birds called fork-tailed drongos (Dicrurus adsimilis) watch for a meerkat or other forager to find desirable prey such as a plump grub. The drongo calls out an alarm as if a predator were approaching. The forager often drops its prize and dashes for cover. Then the drongo swoops in and steals lunch.
If drongos fake an alarm too often, victims could learn to ignore it, says Tom Flower of the University of Cape Town in South Africa. Drongos get around this liars’ dilemma by borrowing other species’ alarm sounds and varying what noise they make in the scam, Flower and his colleagues report in the May 2 Science.