''Hierococcyx'' or hawk-cuckoos is a genus of

birds Birds are a group of warm-blooded vertebrates constituting the class (biology), class Aves (), characterised by feathers, toothless beaked jaws, the Oviparity, laying of Eggshell, hard-shelled eggs, a high Metabolism, metabolic rate, a fou ...

in the family

Cuculidae Cuckoos are birds in the Cuculidae ( ) family, the sole taxon in the order Cuculiformes ( ). The cuckoo family includes the common or European cuckoo, roadrunners, koels, malkohas, couas, coucals, and anis. The coucals and anis are someti ...

. They are distributed in South, Southeast, and East Asia. The resemblance to

hawk Hawks are birds of prey of the family Accipitridae. They are very widely distributed and are found on all continents, except Antarctica. The subfamily Accipitrinae includes goshawks, sparrowhawks, sharp-shinned hawks, and others. This ...

s gives this group the generic name of hawk-cuckoos. They are known to vocalize at their breeding grounds, making identification based on calls easy. It is sometimes included in the genus ''

Cuculus ''Cuculus'' is a genus of cuckoos which has representatives in most of the Old World, although the greatest diversity is in tropical southern and southeastern Asia. Taxonomy The genus ''Cuculus'' was introduced in 1758 by the Swedish naturalist ...

''. It's similarity to hawks gave rise to an ancient belief that cuckoos transformed themself into hawks during the winter months, when cuckoos disappeared from Europe.

Mimicry

Hawk-cuckoos closely resemble accipiters in terms of appearance, an elongated body with long wings and tail, greyish or brownish upperparts with paler barred upperparts, as well as their swift direct flight. Apart from shape and colour, underpart barring tend to increase alarm in small parts. This form of

batesian mimicry Batesian mimicry is a form of mimicry where a harmless species has evolved to imitate the warning signals of a harmful species directed at a predator of them both. It is named after the English naturalist Henry Walter Bates, who worked on butt ...

makes the cuckoo look dangerous to the host, reducing host agression or

Mobbing (animal behavior) Mobbing in animals is an anti-predator adaptation in which individuals of prey species cooperatively attack or harass a predator, usually to protect their offspring. A simple definition of mobbing is an assemblage of individuals around a potenti ...

, resulting in more opportunities for the cuckoo to perform

brood parasitism Brood parasitism is a subclass of parasitism and phenomenon and behavioural pattern of animals that rely on others to raise their young. The strategy appears among birds, insects and fish. The brood parasite manipulates a host, either of the ...

Species

There are eight species:

References

Cuculidae Bird genera Taxa named by Salomon Müller {{Cuculiformes-stub