Fixed-action patterns (FAPs) are instinctual behaviors that are often performed in response to a particular stimulus. The term was first coined by Nobel Prize-winning ethologist Niko Tinbergen in 1951 and is a type of innate behavior that is typically seen in animals. FAPs consist of a sequence of behavior, such as the “head bobbing” of a robin in response to a potential predator.

FAPs are usually elicited by a specific “releaser” stimulus, which has been identified by Tinbergen as “a unique combination of features that is easily recognizable.” This releaser stimulus can take many forms, such as a particular sound, shape, or color. When the stimulus is presented, the animal will automatically perform the FAP. This type of behavior is also known as a “fixed-response.”

FAPs are usually used by animals to communicate with other members of their species or to identify potential threats. For example, the “head bobbing” of a robin is a form of FAP that is used to alert other birds in the area of a potential predator. In addition, FAPs are also used to attract potential mates. For instance, the courtship behavior of a male peacock is a FAP that is designed to attract female peahens.

FAPs are important in understanding the behavior of animals and how they interact with their environment. By studying FAPs, scientists can gain insight into the behavior of animals in different conditions and can also learn about the evolutionary history of certain behaviors. Furthermore, FAPs can also be used to study the development of behavior in young animals, as well as the impact of environmental factors on behavior.

Overall, FAPs are an important type of behavior that can be found in many animals. This type of behavior is often used to communicate, attract mates, or identify potential threats and can be studied to gain insight into animal behavior.


Gill, D. (2008). Fixed action patterns. Oxford Bibliographies.

Lorenz, K. Z. (1935). Der Kumpan in der Umwelt des Vogels. Journal für Ornithologie, 83(1), 137–213.

Tinbergen, N. (1951). The study of instinct. Oxford: Clarendon Press.

Scroll to Top