Long-tailed bird is the cuckoo,
Eggs are laid in the nest of other birds by cuckoo,
Leave the offspring to be hatched and fed by foster-parents of cuckoo,
When hungry make call so loud that it could persuade other birds instead of foster-parents to feed chicks of a cuckoo,

To ensure if foster-parents are feeding chicks the right diet its checked by female cuckoo,
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