Coral-billed ground cuckoo, from Thailand The cuckoo family includes turacos, roadrunners and the hoatzin. Some cuckoos (but not all species) lay eggs in the nests of other species of bird. Animals that trick other species into raising their young like this are called brood parasites. Cuckoos are medium-sized birds with long tails and zygodactyl feet (two toes pointing forwards, two backwards—like those of woodpeckers). They are mostly solitary.
Common cuckoo, Africa, a migrant to Europe and Asia, 32–34 cm (13–13 inches) long, with a wingspan of 55–60 cm (22–24 inches) Reed warbler feeding a common cuckoo
The common cuckoo lays its eggs in the nests of other species of bird, especially the dunnock, meadow pipit and reed warbler. While the host is away, the female cuckoo pushes one egg out of the host's nest, and quickly lays one of her own before flying off. The host, unable to distinguish the cuckoo egg from one of its own, usually—though not always—accepts it as its own. The cuckoo egg soon hatches and the chick kicks the other unhatched eggs out of the nest, thus securing all of the nestlings' food for itself. The adult host cannot tell that the cuckoo chick is not its own, even though, after about two weeks, the cuckoo chick is typically about three times the size of its adult host.
Most types of cuckoo build their own nests, but a number lay their eggs in nests of other birds—and will only reproduce in this way.
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