For every given chemical reaction event, there is a one in a trillion chance that a cosmic ray, or a deity, or the sound of the Boston Pops Orchestra travelling backwards in time will affect the molecules during the reaction and make it different.

Per the laws of thermodynamics, the odds are very high that the interference will make the chemicals simpler. But a further small fraction will accidentally get more complex.

Evolution does >not< mean "march forward in complexity". The overwhelming trend among self-reproducing molecules is towards simplicity. But a primodial soup of self-reproducing molecules will have a further, funny characteristic. If a given proto-cell's chemistry gets simpler, the odds are very high that the simpler cell will be eaten. And if a rare cosmic event makes a cell more complex in just the right way, the odds are now very high that it will eat all the other proto-cells and divide all over the place.

Evolution defeats entropy by exploiting it.

Now the inevitable ideological stance. The above is a good idea, and useful to help us understand cellular mechanics and BioInformatics, but it is still just a model; '''it's not the real thing'''. --PhlIp

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Linkage to EmergentDesign continued at:  http://bioinfo.sarang.net/wiki/EvolutionaryEmbryology
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CategoryEvolution