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[17 Dec 2007|05:55pm] |
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The best definition-in-a-short-paragraph of evolution I've come across to date:
Evolution is descent with modification. Random changes in the genetic makeup of an organism result in changes in the phenotype. The organism interacts with its environment. If the changes to the phenotype give it an advantage over others - the vast majority of genetic changes are deleterious -- it leaves more offspring, who are also endowed with this advantageous genetic makeup for dealing with their environment. This latter is known as "natural selection." This simple but powerful process leads to new species through separation of organisms in time and place.
For such a far-reaching theory, on which so many and such lengthy books have been written, that's a remarkably good (and concise) definition. I think it's also remarkably likely to be comprehensible, if you are aware that the phenotype of an organism is simply the ‘expression’ of its genes—the effects the genes have on the word, such as the organism's physical body, its behaviour, and (if, like me, you agree with Richard Dawkins) secondary artifacts such as caddis fly houses and beaver dams. I may try to memorise this phrasing…
Found here.
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