Nest parasitism is a behavior in which certain bird species, like cowbirds and cuckoos, lay their eggs in the nests of other birds. This strategy allows the parasitic birds to avoid the energy and risks associated with raising their young. The host birds then unknowingly care for the parasitic chicks, often at the expense of their own offspring. The parasitic eggs often mimic the appearance of the host's eggs, increasing the chances of acceptance. This behavior can have significant impacts on the host species, as the parasitic chicks may outcompete the host's young for food and resources, leading to reduced survival rates for the host's offspring.