Cuckoos lay their eggs in other birds' nests in a reproductive strategy known as brood parasitism.
This behavior has evolved as an adaptation to ensure the survival of cuckoo offspring while minimizing the effort and risks associated with raising their own young.
Here's an explanation of why cuckoos engage in this behavior.
Reduced parental investment
Cuckoos, particularly the common cuckoo, are known for their relatively limited parental care abilities.
By laying their eggs in the nests of other bird species, they offload the responsibility of incubating and feeding their chicks onto the unwitting host parents.
This allows cuckoos to conserve energy and resources that would otherwise be expended in raising their own offspring.
Evolutionary advantage
Over time, cuckoos have developed a remarkable ability to mimic the eggs of their host species.
They lay eggs that closely resemble those of the host birds in terms of size, color, and pattern.
This mimicry reduces the chances of host parents detecting the foreign egg and rejecting it from the nest.
Increased chances of survival
Cuckoo chicks often hatch earlier and grow faster than the host's own offspring.
This gives them a competitive advantage for obtaining food from the host parents.
Some cuckoo chicks even employ strategies such as pushing host eggs or chicks out of the nest to ensure they receive all the parental care and resources.
No nest-building or incubation required
Cuckoos do not need to build nests or incubate their eggs, as they rely on the hosts for these tasks.
This frees them from the burdens of nest construction and egg incubation, allowing them to focus on finding suitable host nests and laying eggs.