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Recommended for: Grades 9-12

Resource: Evolution on Double Time

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This excerpt from Evolution: The Triumph of an Idea by Carl Zimmer describes how gene duplication may have been the key to the rapid evolution of the early stages of life on Earth.

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Teachers' Domain, Evolution on Double Time, published September 26, 2003, retrieved on ,
http://www.teachersdomain.org/resource/tdc02.sci.life.evo.doubletime/

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On a geological time scale, it did not take very long for life to evolve from the very first organisms, with a scant few genes, to relatively complex microbes with several thousand genes that were capable of altering the chemistry of the atmosphere and oceans. Gene duplication may explain the speed of this transformation.