Natural Selection and what it didn\'t do for dogs... (Evolution)

by David Turell @, Monday, January 25, 2010, 01:05 (5226 days ago) @ xeno6696


> What exactly do we mean by mutation? I ask this because the variations allowed by sexual reproduction itself is typically the cause of genetic change. As current evolutionary theory stands, these small modifications from generation to generation are carried forward until something triggers a selection event, -You have quoted evolutionary theory properly, but that doesn't mean the theory is correct. Mutations can be due to cosmic rays, mistakes in translation, duplication, epigenetic factors, and 70%, at least, create bad effects or are neutral. We've been over this before. Punctuated Equilibrium, unless you are talking to Gould followers, upsets some folks, since it points to more rapid changes, not explained in the way you have.
>
> Why this ties in with dogs is that this statement shows that the reason the forms of life we see are here, is because of a selection event. It explains adaptation. -There is no question that DNA changes arrange for adaptation. It is also true that humans domesticated wolves that then became dogs, with DNA 98% like wolves, and in fact dogs and wolves breed easily. I've met wolf/dog combos here in Texas and in Alaska. 
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> So do I understand that both you and David would contend that the combinations of sexual reproduction and natural selection are insufficient to describe life's diversity? 
> 
> If so, exhibit A: Dogs.-Dogs were developed actively by human selective breeders. As I have pointed out many times in the past natural selection and mutation are both passive. Mutation depends on chance. Natural Selection depends upon what variations are present, and what challenges nature presents. Species disappear if they cannot respond appropriately.-You state in another note that wolves have never varied like dogs. They have variation depending upon their habitat, but are still wolves. -The two issues, I interpret differently. I am Gouldian in that I'm not sure macroevolution, as you describe it ever occurs. The Cambrian Explosion is, of course, the best example. I don't think wolves and dogs are a different species. They breed easily and one came from the other. Further because of the passivity of mutation and natural selection, I think evolution works in a staccato fashion, not by slow tiny steps, because I think DNA is pre-coded to advance to different very diverse species. And finally, the fossil record may be incomplete, but it currently represents advancement by the method I have described. 
In short, I don't think your wolf approach proves anything. but the underlying article that started the discussion shows what amazing variation can be purposely developed by the intellectual activity of selective breeding. Nature, as we know it, is not very intellectual.


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