Some species have evolved to exploit the FAPs of other species by mimicry of their sign stimuli. Replicating the releaser required to trigger a FAP is known as code-breaking . A well-known example of this is brood parasitism , where one species will lay its eggs in the nest of another species, which will then parent its young. A young North American cowbird , for example, provides a supernormal stimulus to its foster parent, which will cause it to forage rapidly to satisfy the larger bird's demands.  A nestling will provide higher levels of stimulus with noisier, more energetic behavior, communicating its urgent need for food. Parents in this situation have to work harder to provide food, otherwise their own offspring are likely to die of starvation .