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Kelp Gull chicks peck at red spot on mothers beak to stimulate regurgitating reflex.
Kelp Gull chicks peck at red spot on mothers beak to stimulate regurgitating reflex.

In ethology, a fixed action pattern (FAP) is an instinctive behavioral sequence that is indivisible and runs to completion. Ethology ( from Greek ἦθος ethos, "character" and λόγος logos, "knowledge") is the scientific study of Animal Instinct is the inherent disposition of a living Organism toward a particular Behavior. Behavior or behaviour (see spelling differences) refers to the actions or Reactions of an object or Organism, usually Fixed action patterns are invariant and are produced by a neural network known as the innate releasing mechanism in response to an external sensory stimulus known as a sign stimulus or releaser (a signal from one individual to another). In Neuroscience, a neural network describes a population of physically interconnected Neurons or a group of disparate neurons whose inputs or signalling targets define See also Sense A sensory system is a part of the Nervous system responsible for processing sensory information Within Evolutionary biology, signalling theory refers to a body of theoretical work examining communication between individuals

Contents

Examples

The egg rolling behavior of a Greylag Goose is a widely cited example of FAPs.
The egg rolling behavior of a Greylag Goose is a widely cited example of FAPs.

A mating dance may be used as an example. In Biology, mating is the pairing of opposite- Sex or hermaphroditic Organisms for copulation and in Social animals also to raise their Many species of birds engage in a specific series of elaborate movements, usually by a brightly colored male. Birds ( class Aves) are bipedal endothermic ( Warm-blooded) Vertebrate animals that lay eggs. Male (♂ refers to the sex of an organism or part of an organism which produces small mobile Gametes called spermatozoa. How well they perform the "dance" is then used by females of the species to judge their fitness as a potential mate. Female (♀ is the Sex of an Organism, or a part of an organism which produces ova (egg cells The key stimulus is typically the presence of the female. In Physiology, a stimulus is a detectable change in the internal or external environment

Another example of fixed action patterns is the red-bellied stickleback (fish). The Gasterosteidae are a family of Fish including the sticklebacks. The male turns a bright red/blue colour during the breeding season. The breeding season is the most suitable season usually with favorable conditions and abundant food and water for breeding among some wild animals and birds (wildlife This colour change is the fixed action pattern in response to an increasing day length which is the sign stimulus. During this time they are also naturally aggressive towards other red-bellied sticklebacks, another FAP. However anything that is red, or has the appearance or being red, will bring about this FAP. Red is any of a number of similar Colors evoked by light consisting predominantly of the longest wavelengths of Light discernible by the human eye in the wavelength The proximate response to this is that due to the stimuli, a nerve sends a signal to attack that red item. The ultimate cause of this behavior stems from the fact that the stickleback needs the area in which it is living for either habitat, food, mating with other sticklebacks, or other purposes. This interaction was studied by Niko Tinbergen. Nikolaas "Niko" Tinbergen ( April 15, 1907 &ndash December 21, 1988) was a Dutch ethologist and Ornithologist

Another well known case is the classic experiments by Tinbergen and Lorenz on the Graylag Goose. Konrad Zacharias Lorenz ( November 7, 1903 in Vienna &ndash February 27, 1989 in Vienna) was an Austrian Like similar waterfowl, it will roll a displaced egg near its nest back to the others with its beak. See also UK Wildfowl and Wetlands Trust USA Ducks Unlimited In most Birds and Reptiles an egg ( Latin ovum) is the Zygote, resulting from Fertilization of the Ovum. The sight of the displaced egg triggers this mechanism. If the egg is taken away, the animal continues with the behavior, pulling its head back as if an imaginary egg is still being maneuvered by the underside of its beak. However, it will also attempt to move other egg shaped objects, such as a golf ball, door knob, or even an egg too large to have possibly been laid by the goose itself (a supernormal stimulus). A superstimulus or superreleaser is an exaggerated version of a stimulus to which there is an existing response tendency or any stimulus that elicits a response more [1]

Yawning behavior is seen in many animals
Yawning behavior is seen in many animals

Although fixed action patterns are most common in animals with simpler cognitive capabilities, humans also demonstrate fixed action patterns. For example, infants grasp strongly with their hands as a response to tactile stimulus. This is thought to be a vestigial mechanism where when threatened by a predator a young primate would grab on to a parent's fur so the parent could climb to safety without having to hold its child (see also reflex action). Vestigiality describes homologous characters of Organisms which have lost all or most of their original function in a species through A reflex action, also known as a reflex, is an involuntary and almost instant movement in response to stimulus. Another FAP shared by some animals, including humans, is yawning, which often triggers yawning in other individuals. A yawn (from the Middle English yanen, an alteration of yonen or yenen, which in turn comes from the Old English geonian Yawns last around 6 seconds and are difficult to stop once initiated. Yawning, whether seen, heard or both, then serves as a releaser in nearby animals. [2]

Mimicry

Brood parasites provide a supernormal stimulus to the parenting species.
Brood parasites provide a supernormal stimulus to the parenting species.

Some species have evolved to exploit the fixed action patterns of other species by mimicry of their sign stimulus. Biological mimicry occurs when a group of organisms the mimics, have Replicating the releasing mechanism 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. Brood parasites are organisms that use the strategy of brood-parasitism, a kind of Kleptoparasitism found among Birds Fish or Insects A young North American cowbird, for example, provides a supernormal stimulus to its parent, which will cause it to forage rapidly in order to satisfy the larger bird's demands. Cowbirds are Birds belonging to the genus Molothrus in the family Icteridae. [3] In a natural situation a nestling will provide higher levels of stimulus with noisier, more energetic behavior, communicating its urgent need for food. Parents in this situation should work extra hard to provide food, otherwise their own offspring are likely to die of starvation. Starvation (also called inanition) is a severe reduction in Vitamin, Nutrient, and Energy intake and is the most extreme form of

References

Cited

  1. ^ Tinbergen, N. (1951) The Study of Instinct. Nikolaas "Niko" Tinbergen ( April 15, 1907 &ndash December 21, 1988) was a Dutch ethologist and Ornithologist Oxford University Press, New York.
  2. ^ Provine, R. R. (1986) Yawning as a stereo-typed action pattern and releasing stimulus. Ethology 72:109-122.
  3. ^ Wickler, W. (1968) Mimicry in Plants and Animals. World University Library, London.

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