- Foster's rule
Foster's rule (also known as the island rule) is a principle in
evolutionary biology stating that members of aspecies get smaller or bigger depending on the resources available in the environment. This is the core of the study ofisland biogeography . For example, it is known thatpygmy mammoth s evolved from normalmammoth s on smallisland s. Similar evolutionary paths have been observed inelephant s,hippopotamus es, boas,deer , andhuman s.It was first stated by
J. Bristol Foster in1964 in the journal "Nature", in an article titled "The evolution of mammals on islands." In it, he studied 116 island species and compared them to their mainland varieties. He proposed that certain island creatures evolved into larger versions of themselves while others became smaller versions of themselves. For this, he proposed the simple explanation that smaller creatures get larger in the absence of thepredator s they had attracted on the mainland and larger creatures become smaller with the absence of food sources.Later, that idea was expanded upon by the publication of "
The Theory of Island Biogeography ", byRobert MacArthur andEdward O. Wilson . And in1978 ,Ted J. Case published a much longer and more complex paper on the topic in the journal "Ecology". Case also demonstrated that Foster's original conjecture for the reason all this happened was not completely true and was oversimplified.References
* Foster, J. B. (1964) The evolution of mammals on islands. "Nature" 202, 234 235.
* Foster, J. B. (1965) The evolution of the mammals of the Queen Charlotte Islands, British Columbia. "Occ. papers of the B. C. Prov. Museum, 14, 1-130
* Case, T. J. (1978) A general explanation for insular body size trends in terrestrial vertebrates. "Ecology", 59, 1-18.See also
*
Island dwarfing
*Island gigantism
*Homo floresiensis External links
* [http://www.pbs.org/wgbh/nova/eden/giants.html Why Do Islands Breed Giants (And Sometimes Dwarfs)?]
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