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Allens rule

Allen's rule A corollary to Bergmann's rule and Gloger's rule, holding that a race of warm-blooded species in a cold climate typically has shorter protruding body parts (nose, ears, tail, and legs) relative to body size than another race of the same species in a warm climate. This is because long protruding parts emit more body heat, and so are disadvantageous in a cool environment but advantageous in a warm environment. The idea is disputed, critics pointing to many other adaptations for heat conservation which are probably more important, notably fat layers, feathers, fur, and behavioural adaptations to avoid extreme temperatures. The rule was proposed by the American zoologist J. A. Allen in 1876.

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Allens rule

Allen's rule A corollary to Bergmann's rule and Gloger's rule, holding that a race of warm-blooded species in a cold climate typically has shorter protruding body parts (nose, ears, tail, and legs) relative to body size than another race of the same species in a warm climate. This is because long protruding parts emit more body heat, and so are disadvantageous in a cool environment, but advantageous in a warm environment. The idea is disputed, critics pointing to many other adaptations for heat conservation which probably are more important, notably fat layers, feathers, fur, and behavioural adaptations to avoid extreme temperatures.

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"Allens rule." A Dictionary of Earth Sciences. . Encyclopedia.com. 23 Jan. 2018 <http://www.encyclopedia.com>.

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"Allens rule." A Dictionary of Earth Sciences. . Retrieved January 23, 2018 from Encyclopedia.com: http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/allens-rule

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Notes:
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Allen's rule

Allen's rule A corollary to Bergmann's rule and Gloger's rule, holding that a race of warm-blooded species in a cold climate typically has shorter protruding body parts (nose, ears, tail, and legs) relative to body size than another race of the same species in a warm climate. This is because long protruding parts emit more body heat, and so are disadvantageous in a cool environment, but advantageous in a warm environment. The idea is disputed, critics pointing to many other adaptations for heat conservation which probably are more important, notably fat layers, feathers, fur, and behavioural adaptations to avoid extreme temperatures.

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"Allen's rule." A Dictionary of Zoology. . Encyclopedia.com. 23 Jan. 2018 <http://www.encyclopedia.com>.

"Allen's rule." A Dictionary of Zoology. . Encyclopedia.com. (January 23, 2018). http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/allens-rule-0

"Allen's rule." A Dictionary of Zoology. . Retrieved January 23, 2018 from Encyclopedia.com: http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/allens-rule-0

Learn more about citation styles

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Encyclopedia.com gives you the ability to cite reference entries and articles according to common styles from the Modern Language Association (MLA), The Chicago Manual of Style, and the American Psychological Association (APA).

Within the “Cite this article” tool, pick a style to see how all available information looks when formatted according to that style. Then, copy and paste the text into your bibliography or works cited list.

Because each style has its own formatting nuances that evolve over time and not all information is available for every reference entry or article, Encyclopedia.com cannot guarantee each citation it generates. Therefore, it’s best to use Encyclopedia.com citations as a starting point before checking the style against your school or publication’s requirements and the most-recent information available at these sites:

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American Psychological Association

http://apastyle.apa.org/

Notes:
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  • In addition to the MLA, Chicago, and APA styles, your school, university, publication, or institution may have its own requirements for citations. Therefore, be sure to refer to those guidelines when editing your bibliography or works cited list.