the quickest hatching time is for the cuckoo. some types of cuckoos take only 10 days. this means that when they hatch in the nest of their "foster parents", the eggs that the parents have laid are not yet ready. newborn cuckoos are naked, blind and ugly, but they are strong. they get under any eggs that are in the nest and throw them out before they hatch. that means that the cuckoo has the whole care of both parents. baby cuckoos grow fast and often get bigger than the parents who feed them.