Preadaptation

Preadaptation

In evolutionary biology, preadaptation describes a situation where an organism uses a preexisting anatomical structure inherited from an ancestor for a potentially unrelated purpose. One example of preadaptation is dinosaurs having used feathers for insulation and display before using them to fly, or sweat glands in mammals being transformed into mammary glands.

Another example is the hypothesis proposed by zoologist Jonathan Kingdon that before early humans became bipedal, they began engaging in squat feeding, i.e. turning over rocks and leaves to find insects, worms, snails and other food. Consequently, they adapted flatter feet than were necessary in their previous tree-dwelling ancestors, since that makes squatting much easier. Flatter feet are also extremely useful for bipedal animals, so they can be described as a preadaptation to bipedalism, even though (or rather because) the adaptation had nothing to do with bipedalism originally.

Some biologists dislike the term "'pre"adaptation' as it could imply an intentional plan, which is contrary to the nature of evolution. Some alternative terms that have been suggested include "co-option" and exaptation.

ource

*Bickerton, Derek (2000). "Biomusicology and Language Evolution Studies", "The Origins of Music". Cambridge, Mass: A Bradford Book, The MIT Press. ISBN 0-262-23206-5.


Wikimedia Foundation. 2010.

Игры ⚽ Нужно сделать НИР?

Look at other dictionaries:

  • préadaptation — ● préadaptation nom féminin Ensemble de traits anatomiques et physiologiques d une population animale ou végétale qui lui seraient avantageux dans un milieu différent de celui où vit actuellement l espèce et qui rendent possible la conquête, par… …   Encyclopédie Universelle

  • preadaptation — [prē΄ad əp tā′shən] n. the possession of certain characteristics by an organism which make it more adaptable to a future environmental change than similar organisms are preadaptive adj …   English World dictionary

  • preadaptation — preadaptacija statusas T sritis Kūno kultūra ir sportas apibrėžtis Dėl mutacijos organizmo ar organo savybė prisitaikyti prie būsimų aplinkos pokyčių arba prie būsimų organų funkcijų. kilmė lot. prae – anksčiau + adaptacija atitikmenys: angl.… …   Sporto terminų žodynas

  • preadaptation — preadaptacija statusas T sritis augalininkystė apibrėžtis Atsiradimas augalo požymių, kurie neturi pirminės prisitaikymo reikšmės, bet pasikeitusiomis gyvenimo sąlygomis gali būti naudingi. atitikmenys: angl. preadaptation rus. преадаптация …   Žemės ūkio augalų selekcijos ir sėklininkystės terminų žodynas

  • preadaptation — noun Date: 1886 a character of an organism or taxonomic group that takes on a function when none previously existed or that differs from its existing function which has been derived by evolution; also the possession of one or more such characters …   New Collegiate Dictionary

  • preadaptation — n. [L. pre, before; adaptatus, fitted] The possession of the necessary genotypic or phenotypic properties that permit a shift into a new niche or habitat …   Dictionary of invertebrate zoology

  • preadaptation — /pree ad euhp tay sheuhn/, n. Biol. a structure or property that developed in an ancestral stock and was useful in a descendant in a changed environment. [1885 90; PRE + ADAPTATION] * * * …   Universalium

  • preadaptation — noun An adaptation that evolved in an ancestral population, in which it served a different function …   Wiktionary

  • preadaptation — pre·adap·ta·tion (pre″a dap taґshən) the acquisition in an ancestral group of certain characters that usually are adaptive to the ancestral mode of life yet at the same time enable a shift in mode of life; for example, lungs in fish… …   Medical dictionary

  • preadaptation — pre·adaptation …   English syllables

Share the article and excerpts

Direct link
… Do a right-click on the link above
and select “Copy Link”