brood parasitism

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brood parasitism

zoology

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June 17, 2026

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Brood parasitism is a form of social parasitism, primarily observed in birds, where one species lays its eggs in the nest of another species and provides no parental care. The host bird then incubates the eggs and raises the young parasite as its own. This behavior is notably practiced by most cuckoos and all cowbirds. While some brood parasites, like certain cuckoos, may remove host eggs, others, such as cowbirds, do not necessarily harm the host's brood. This strategy allows the parasitic parent to conserve energy and time by avoiding nesting and chick-rearing duties.1234

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bird
Nesting
…or other external sources, and brood parasites such as cuckoos and cowbirds, which lay their eggs in the nests of other species. Murres and the king and emperor penguins build no nest but incubate with the egg resting on top of the feet.
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…or other external sources, and brood parasites such as cuckoos and cowbirds, which lay their eggs in the nests of other species. Murres and the king and emperor penguins build no nest but incubate with the egg resting on top of the feet.
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bumblebee
Cuckoo bumblebees
The former Psithyrus species are brood parasites. They are often called cuckoo bumblebees because they lay eggs in the nests of social bumblebees in a manner analogous to some cuckoos (bird order Cuculiformes), which lay eggs in the nests of other birds. Cuckoo bumblebees, having no worker caste, enter the…
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The former Psithyrus species are brood parasites. They are often called cuckoo bumblebees because they lay eggs in the nests of social bumblebees in a manner analogous to some cuckoos (bird order Cuculiformes), which lay eggs in the nests of other birds. Cuckoo bumblebees, having no worker caste, enter the…
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cuckoo wasp
All cuckoo wasps are brood parasites, mostly exploiting bee or wasp larvae. More than 1,000 species of the genus Chrysis alone have been described.
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All cuckoo wasps are brood parasites, mostly exploiting bee or wasp larvae. More than 1,000 species of the genus Chrysis alone have been described.
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mimicry
Cuckoos
…cuckoo (Cuculus canorus) is a brood parasite; i.e., it lays its eggs in the nests of other birds, which act as foster parents for the young cuckoos. The most frequent foster parents are various species of small songbirds. Although the eggs of the various host species span a great range…
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…cuckoo (Cuculus canorus) is a brood parasite; i.e., it lays its eggs in the nests of other birds, which act as foster parents for the young cuckoos. The most frequent foster parents are various species of small songbirds. Although the eggs of the various host species span a great range…
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piciform
Reproduction
…of the honey guides are brood parasites, laying their eggs in the nests of other species, especially those that nest in holes or in deep, covered nests. The host’s eggs often are punctured by the female honey guide when she lays her own egg. Only a single egg is laid…
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…of the honey guides are brood parasites, laying their eggs in the nests of other species, especially those that nest in holes or in deep, covered nests. The host’s eggs often are punctured by the female honey guide when she lays her own egg. Only a single egg is laid…
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parasitism
…different form of parasitism called brood parasitism is practiced by most species of cuckoos and all cowbirds. Those birds do not build nests of their own but deposit their eggs in the nests of other species and abandon them there, with the hope that adult birds of other species will…
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…different form of parasitism called brood parasitism is practiced by most species of cuckoos and all cowbirds. Those birds do not build nests of their own but deposit their eggs in the nests of other species and abandon them there, with the hope that adult birds of other species will…
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