'Cuckoos use multiple disguise to fool other birds'
London: Cuckoo birds use multiple disguise to lay their eggs in other birds' nests, to avoid raising their own chicks.
While studying the behaviour of common cuckoos, Cambridge University researchers found that social learning or learn from the behaviour of others might play a larger role in animal mimicry or the art of disguise.
Cuckoos are known as brood parasites, which mean that they sneak their eggs into other birds' nests so that they don't have to raise their own chicks.
Some female cuckoos have evolved feathers that resemble a sparrow hawk, a common predator of song birds. These disguised, or mimicking, cuckoos are able to approach the nests of other birds, like reed warblers, without being attacked by the original owner of the nest.
The mimicking cuckoos come in two different forms either gray or reddish-brown and a the study shows whenever reed warblers become brave enough to attack intruding cuckoos, other reed warblers in the area take notice.
According to the researchers Rose Thorogood and Nicholas Davies, reed warblers that witness other warblers attacking a cuckoo are more likely to defend their own nests against mimicking cuckoos of the same colour.
However, cuckoos of the other colour are still able to fool the reed warblers and sneak into their nests without being attacked, the study said.
The study suggests that the social information spread among reed warblers about which mimicking cuckoos to attack has led to the evolution of both gray and reddish-brown colour in the cuckoos, who remain a successful brood parasite.