Historical Development and Mechanisms of Evolution and Natural Selection: Introduction
Introduction
Did a giraffe's neck grow to great lengths for the animal to survive or because organisms with increasingly longer necks reproduced more effectively and, hence, had a greater chance of passing on their genes than the short-necked variety? This is an interesting question with many answers; you will know the correct one soon.
This section may save you the trouble of stretching to become taller; it will also present you with one of the great dilemmas that is still with us. Hopefully you can solve it. Darwin's theories are presented in a historical context so you can develop the sense of understanding in incremental, sequential units that may stay with you for a while, at least through the next test. You will also be able to visualize the effects of natural selection on population trends. This is good stuff!
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Excerpted from The Complete Idiot's Guide to Biology © 2004 by Glen E. Moulton, Ed.D.. All rights reserved including the right of reproduction in whole or in part in any form. Used by arrangement with Alpha Books, a member of Penguin Group (USA) Inc.
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