Releasers triggered through other senses include the sound of their chick’s distress calls, causing mother hens to respond (yet not the sight of chicks in trouble) and chemical stimuli such as pheromones triggering mating between insects.
Releasers initiate specific behaviour automatically. Herring gull chicks know from birth to peck at a red spot on their parents’ bills to get food, and red dots on moving pencils or models will instantly produce the response also. Birds have an escape response to the visual silhouette of predatory birds (which have short necks). However when silhouettes had longer necks no response would be produced.
Motor programs are cases of innate behaviour that will continue to completion once triggered, regardless of any other input. A famous example of such behaviour is egg rolling by geese. If an egg becomes visibly isolated, it triggers an innate response to roll it back to the nest. However if the egg is removed mid-roll, the goose will continue to ‘roll’ the non-existent egg.
Innate behaviour is genetically determined, similar in all members of the species, is not always fully developed at birth (as it can be modified by learning) and occurs in response to a releaser. Innate behaviour has many sub categories such as: Maintenance/homeostatic, rhythmic, communication and social. It should be noted however that communication and social behaviour are particular examples, which can also fall into the learned behaviour category.
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