Fixed Action Pattern (FAP)
A fixed action pattern (FAP) is an instinctive activity pattern that causes animals to act in a specific behavior pattern unique to their species. It is a pattern that is relatively invariant within species and normally plays itself out to completion even if interrupted. These action patterns are produced by a mechanism that is called an innate releasing mechanism that is produced within a neural network. An example of this is the "egg-rolling" response that is elicited by an egg that has rolled out of the nest. The mother bird will instinctively roll the egg, or what is perceived as an egg (rock, golf ball, etc.) back to the nest. This behavior continues even if the egg is removed from the scene (as in a researcher taking the egg-object away).