General Theory of Evolution

[b]Defiant Heretic: Welcome to evcforum! Excellent post. You'll find that there are a number of different creationist points of view represented here. I think Peter Borger, especially, might have comments on your presentation (he feels that the neo-Darwinian theory has been falsified, and that natural selection is invalid). I'll be curious to hear his replies.Again, welcome to the forum...

Just for reference Peter, you seem to be misunderstanding a bit:

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BIOLOGICAL solutions to competitive pressures can represent either NO increasing or decreasing complexity DUE TO A MULTI PURPOSE GENOME THAT ALLOWS ORGANISMS TO RESPOND RAPIDLY TO CHANGING ENVIRONMENTS. For example, the cheetah migrates into a new habitat putting the local gazelles under competitive pressure to become more evasive.

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This is something of a mis-statement. A change in the selection pressures in a given organism's environment don't cause the organism to change. This is the fallacy of "upward" or progressive evolution you keep talking about. Selection pressures on a population tend to favor the survival of individuals with certain characteristics, primarily be weeding out those individuals who don't have those characteristics. Eventually, the "favored" characteristics will come to predominate in the population. To use your own example, the introduction of cheetahs into an environment where gazelles have never faced cheetah predation will not cause anything like an "upward pressure" forcing gazelles to get more evasive. What happens is the "slow" gazelles get eaten, the "fast" (comparatively) survive at least long enough to reproduce. Therefore, "fast" traits get passed down to the next generation. Remember the old joke about the two guys being chased by the bear: "Why are you putting on tennis shoes? You can't outrun a bear.", one says. The other responds, "I don't have to outrun the bear. I only have to outrun you." Natural selection works to favor the guy with tennis shoes...

I'd like to request that everyone calm the hell down, take a step back, breathe deeply, and quit with the ad homs? We're not adding anything to the discussion, here. Thanks.

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Exactly my point. The DNA of the fast animals is already in the genepool of the multipurpose genome. A bit of shuffling, a bit of (non-)random mutations and voila a "new" faster population after a couple of generations! New genes? NO. Different organisation? Maybe. Distinct gene regulation? Sure.

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Unfortunately, I think you missed my point. In that particular example, the phenotypical traits for "fast" and "slow" were already present in the genome. I certainly agree that the gradual shift in frequency between "fast" and "slow" alleles in the population under selection pressure doesn't represent new genetic material. However, these genes are not "turned on" by selection - they are already expressed phenotypical variations. However, the variations are introduced by random mutation - not directed by the environment. If random mutation HAD NOT already produced the variation, there would have been nothing for natural selection to act upon in the first place. If you look at it in a different way, if there were no variation - no "fast" alleles that provided an advantage in this case - the population would go extinct. Since we can see this type of local extinction occurring regularly (c.f., "sanctuary effect" and "island effect" in the context of deforestation, for instance), this is a pretty solid statement. Hence, your concept of a multipurpose genome that provides genes which are "turned on" due to environmental effects has NOT been observed.

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Yes, I remember. It was a joke, wasn't it? And that is why everyone is wearing Nikes, nowadays?

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Yes, it is a joke. However, it is quite illustrative of how natural selection works. Consider, in context: if bear predation was a significant selection pressure and the posession of tennis shoes (the Nike trait?) was the variation that gave an organism increased marginal fitness against non-tennis-shoe-wearers, then YES, everyone would at some point be wearing Nikes - because everyone who didn't have them would have been eaten. Of course, that means the bears would either die out OR a lucky mutation would give them some advantage (e.g., roller-skates) in order to keep up the evolutionary arms race. Losers in evolution are called "extinct". Our bears would accidently have to have received roller-skates to survive. If they didn't, they'd be a historical footnote.