Content deleted Content added
BrayLockBoy (talk | contribs) |
|||
Line 57:
== Evolutionary disadvantages ==
[[File:Reed_warbler_cuckoo.jpg|thumb|Brood parasites, such as the [[European cuckoo|cuckoo]], provide a supernormal stimulus to the parenting species.]]
Fixed action patterns are predictable, as they are invariable, and therefore can lead to exploitation.<ref name=":122">{{Cite web |url=https://www.sciencedirect.com/topics/medicine-and-dentistry/fixed-action-pattern |title=Fixed Action Pattern – an overview {{!}} ScienceDirect Topics |website=www.sciencedirect.com |access-date=2019-10-24}}</ref> Some species have evolved to exploit the fixed action patterns of other species by [[mimicry]] of their sign stimuli.<ref name=":132"/> Replicating the releaser required to trigger a fixed action pattern is known as ''code-breaking''.<ref>{{Cite web|url=https://www.nature.com/scitable/knowledge/library/the-ecology-of-avian-brood-parasitism-14724491/|title=The Ecology of Avian Brood Parasitism {{!}} Learn Science at Scitable|website=www.nature.com|access-date=2019-10-24}}</ref> 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.<ref name=":132"/> A young [[North American cowbird]], for example, provides a supernormal stimulus to its foster parent, which will cause it to forage rapidly to satisfy the larger bird's demands.<ref name=":5">Wickler, W. (1968) ''Mimicry in Plants and Animals.'' World University Library, London.</ref> A nestling will provide higher levels of stimulus with noisier, more energetic behavior, communicating its urgent need for food.<ref name=":5" /> Parents in this situation have to work harder to provide food, otherwise their own offspring are likely to die of [[starvation]].<ref name=":5" />
=== Brood parasitism ===
The exploitation of sign stimuli can be seen when exploring the concept of [[Brood parasite|brood parasitism]]. Other animals will learn the sign stimuli of different species and use it to manipulate the other animal into doing something for its own benefit. An example of this can be seen in the [[European cuckoo]]. This particular species of bird benefits by handing off the task of raising their young to other species of birds who will care for any egg that is found in its nest. In this case the sign stimulus is the presence of the eggs in the nest. If the other bird does not recognize the other bird's egg as foreign, it will continue on caring for it as its own by incubating it and hatching it. Once it is hatched, the young cuckoo ensures for itself a solid upbringing by instinctively pushing its neck around anything that is solid in the nest and pushing it over the edge. Thus classifying the sign stimulus as any solid object. This allows for the cuckoo's
== Exceptions ==
| |||