∞ generated and posted on 2016.08.30 ∞
A behavior that occurs seemingly without thought and, once released, is carried out to completion.
Fixed-action patterns (FAP) require relatively little thought or thinking on the part of the animal performing the behavior. What is known as a sign stimulus "releases" the action, that is, an environmental signal stimulates or induces the action to take place.
The following is a FAP consisting of egg-rolling behavior by a greylag goose. Note how the goose completes the action even after it is no longer accomplishing anything, i.e., towards getting the round object found immediately outside of the nest (which typically would be an egg) back into the nest and under the bird:
Because fixed-action patterns occur essentially without thought, their results can be rather silly when they occur within novel contexts, such as when researchers (or pet owners) go out of their way to "fool" their poor charges such that a fixed-action pattern is performed inappropriately.
The following video shows inappropriate chick "rolling" behavior as taken by former student Steffani Jijon: