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neoteny
neoteny , in biology, sexual maturity reached in the larval stage of some animals. Certain environmental conditions can inhibit the completion of metamorphosis; low temperature or lack of available iodine retard the action of the thyroid gland, the larval form may mature sexually, mate, and produce fertile eggs. If environmental conditions improve, neoteny is reversible; i.e., the larvae can complete metamorphosis and attain normal maturity. When neoteny occurs in some salamanders (see axolotl ), they remain aquatic. In insects, reproduction in the larval stages is known as paedogenesis; it occurs in certain beetles and gall midges. In the midges, the daughter larvae produced within a mother larva consume the mother and escape; the process may continue for several generations. |
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"neoteny." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "neoteny." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1E1-neoteny.html "neoteny." The Columbia Encyclopedia, 6th ed.. 2011. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1E1-neoteny.html |
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neoteny
neoteny A form of heterochrony that involves the slowing down in a descendant of part or all of its ancestor's rate of development, so that at least some aspects of the descendant resemble a (generally large-sized) juvenile stage of the ancestor. This may lead to paedomorphosis. Since the juvenile stages of many organisms are less specialized than the corresponding adult stages, such shifts allow the organisms concerned to switch to new evolutionary pathways (see evolution). The word comes from the Greek neos (meaning ‘youthful’). Neoteny is common among Urodela (newts and salamanders) and some features of human evolution (e.g. lack of body hair) have been ascribed to it.
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MICHAEL ALLABY. "neoteny." A Dictionary of Ecology. 2004. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. MICHAEL ALLABY. "neoteny." A Dictionary of Ecology. 2004. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O14-neoteny.html MICHAEL ALLABY. "neoteny." A Dictionary of Ecology. 2004. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O14-neoteny.html |
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neoteny
neoteny A form of heterochrony that involves the slowing down in a descendant of part or all of its ancestor's rate of development, so that at least some aspects of the descendant resemble a (generally large-sized) juvenile stage of the ancestor. This may lead to paedomorphosis. Since the juvenile stages of many organisms are less specialized than the corresponding adult stages, such shifts allow the organisms concerned to switch to new evolutionary pathways. The word comes from the Greek neos (meaning ‘youthful’). Neoteny is common among Urodela.
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Cite this article
MICHAEL ALLABY. "neoteny." A Dictionary of Zoology. 1999. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. MICHAEL ALLABY. "neoteny." A Dictionary of Zoology. 1999. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O8-neoteny.html MICHAEL ALLABY. "neoteny." A Dictionary of Zoology. 1999. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O8-neoteny.html |
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neoteny
neoteny Slowing down of bodily development, so that sexual maturity is achieved while the organism still looks like a juvenile; this leads to paedomorphosis. Since the juvenile stages of many organisms are less specialized than the corresponding adult stages, such shifts allow the organisms concerned to switch to new evolutionary pathways. The word comes from the Greek neos (meaning ‘youthful’). Some features of human evolution have been ascribed to neotony.
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AILSA ALLABY and MICHAEL ALLABY. "neoteny." A Dictionary of Earth Sciences. 1999. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. AILSA ALLABY and MICHAEL ALLABY. "neoteny." A Dictionary of Earth Sciences. 1999. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O13-neoteny.html AILSA ALLABY and MICHAEL ALLABY. "neoteny." A Dictionary of Earth Sciences. 1999. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O13-neoteny.html |
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neoteny
neoteny The retention of the juvenile body form, or particular features of it, in a mature animal. For example, the axolotl, a salamander, retains the gills of the larva in the adult. Neoteny is thought to have been an important mechanism in the evolution of certain groups, such as humans, who are believed to have developed from the juvenile forms of apes. See also heterochrony.
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"neoteny." A Dictionary of Biology. 2004. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "neoteny." A Dictionary of Biology. 2004. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O6-neoteny.html "neoteny." A Dictionary of Biology. 2004. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O6-neoteny.html |
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