Thaindian News

Washington, April 18 (ANI): Scientists have said that cuckoos have evolved plumage patterns that give them a hawk-like appearance to scare the birds whose nests they invade.

A study has shown that reed warblers - a cuckoo host species - are less likely to attack more “hawk-like” cuckoos.

This helps the parasitic birds to lay their eggs undisturbed.

The visible similarity between cuckoos and sparrow hawks was already clear, but this is the first study to show the effect the trickery has on host birds.

Cuckoos are brood parasites; after laying an egg in another bird’s nest, they leave the unsuspecting host to raise their chick.

To fool their victims into caring for their young, cuckoos first need to lay an egg in the right nest, without being “mobbed” or attacked by the nest’s owner.

“We noticed in another experiment that great tits and blue tits were just as afraid of cuckoos as they were of sparrow hawks,” BBC quoted Justin Welbergen from the University of Cambridge, UK, who led this research, as saying.

“The most striking similarity between a cuckoo and a sparrow hawk is the bar patterns on [both species'] underbellies,” he said.

Welbergen said this showed how “hawk mimicry” helps cuckoos to gain better access to reed warblers’ nests in order to lay their eggs.

The study is detailed in the journal Behavioural Ecology. (ANI)