The flight of the cuckoo is short and weak, so to prevent fatigue they sometimes travel on the backs of kites. Their saliva produces the insect known as cicada. The cuckoo puts its eggs in with those of other birds to be raised by them. <

Pliny the Elder claims that the cuckoo is a kind of hawk, which it becomes at some times in the year; his proof is that the cuckoo and the hawk are rarely seen at the same time.

The cuckoo is one of several kinds of birds that lays their eggs in ither birds' nests. The host birds do not seem to notice that the cuckoo chicks are different, and treat them as their own.