Cuckoo in the Nest

The cuckoo bird is known for leaving its eggs in other birds' nests. The cuckoo hatchling's beaks are usually larger than the others', and the mother bird ends up feeding the cuckoo more than the others, who end up starving or being overcrowded by the massive cuckoo hatchling. The mother bird continues to care for the cuckoo hatchling, even when all her other children are dead.