What is Universal Common Descent

What is Universal Common Descent - What is Universal Common...

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What is Universal Common Descent? niversal common descent is the hypothesis that all living, terrestrial organisms are genealogically related. All existing species originated gradually by biological, reproductive processes on a geological timescale. Modern organisms are the genetic descendants of one original species or communal gene pool. Genetical "gradualness", a much misunderstood term, is a mode of biological change that is dependent on population phenomena; it is not a statement about the rate or tempo of evolution. Truly genetically gradual events are changes within the range of biological variation expected between two consecutive generations. Morphological change may appear fast, geologically speaking, yet still be genetically gradual ( Darwin 1872 , pp. 312-317 ; Dawkins 1996 , p.241; Gould 2002 , pp. 150-152; Mayr 1991 , pp. 42-47; Rhodes 1983 ). Though gradualness is not a mechanism of evolutionary change, it imposes severe constraints on possible macroevolutionary events. Likewise, the requirement of gradualness necessarily
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This note was uploaded on 11/14/2011 for the course BIO BSC1010 taught by Professor Gwenhauner during the Fall '10 term at Broward College.

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What is Universal Common Descent - What is Universal Common...

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