The gentle air of spring carries the sweet first call of the cuckoo. It is a sound that has captivated cultures for centuries, signalling the end of the dark days of winter. Yet the innocent birdsong belies a cunning nature. The cuckoo is the most famous cheat in the feathered kingdom: never building her own nest, the female cuckoo instead lays her eggs in those of other birds. When the cuckoo’s egg hatches, the chick sets to work on murdering the other hatchlings by pushing them over the edge, leaving the cuckoo chick to be reared alone by the host bird. Thus the female cuckoo has succeeded in “cuckoldry”, her victim a “cuckold”.