Brood parasite

Brood parasites are organisms that rely on others to raise their young. The strategy appears among insects, fishes, and birds. The brood parasite manipulates a host, either of the same or of another species, to raise its young as if it were its own.

Brood parasitism relieves the parasitic parents from the investment of rearing young or building nests for the young, enabling them to spend more time on other activities such as foraging and producing further offspring. Bird parasite species mitigate the risk of egg loss by distributing eggs amongst a number of different hosts. As this behaviour damages the host, it often results in an evolutionary arms race between parasite and host.