 The common cuckoo , a brood parasite , provides examples of mimesis both in the adult and in the egg . The female lays her eggs in nests of other , smaller species of bird , one per nest . The female mimics a sparrowhawk . The resemblance is sufficient to make small birds take action to avoid the apparent predator . The female cuckoo then has time to lay her egg in their nest without being seen to do so . The cuckoo 's egg itself mimics the eggs of the host species , reducing its chance of being rejected . 
