A cuckoo finch in sheep's clothing »

Cuckoo finches in Africa have adopted a unique disguise to help them lay their eggs in other birds' nests, biologists have found. "The cuckoo finch in Zambia has evolved to be almost indistinguishable from common and harmless female weaver birds, such as the southern red bishop", said Dr William Feeney, who conducted the study during his PhD at ANU Research School of Biology. "The cuckoo finch is so similar to the innocent bishops, that the target of the trickery, the tawny-flanked prinia, cannot tell them apart," said Dr Feeney, who has now taken a position at the University of Cambridge, UK. "The cuckoo finch looks a lot more similar to the bishop than its nearest relatives, the Vidua finches, suggesting that it has evolved to be able to hang around prinia nests without arousing suspicion," he said. Cuckoo finches, like the iconic cuckoos, are brood parasites who lay their eggs in the nests of other birds, to deceive them into raising the parasitic young as their own. Brood parasites use a range of methods to deceive their hosts, as hosting a brood parasite is costly and hosts defend themselves against brood parasitism. However, Dr Feeney's research is the first to find that an adult brood parasite has evolved to look harmless in an attempt to fool their host.