Epigenetics: through phenotype changes? (Introduction)

by dhw, Wednesday, January 14, 2015, 19:55 (3602 days ago) @ David Turell

DAVID: Do animals have control over their evolution through choosing minor changes in habits that modify their bodies:-"What they are saying is something subtler. Over their lifetimes, living things make all sorts of adjustments to their physical being - what biologists call the phenotype, as opposed to the genetic make-up, or genotype - to get along better in the environment they find themselves in. They grow differently based on how they use their bodies, they turn certain genes on and others off, they learn new behaviours, and so on.
"None of these changes count as evolution, because they don't directly change the organism's genetic make-up. But they do shape the way natural selection acts on these genes, and in that way they push evolution in a different direction. In effect, the genes, which we have always thought of as occupying the driver's seat, have slid over to let the phenotype take the wheel. When the phenotype changes for some purpose, the genes that enhance that response might come along for the ride."

http://www.newscientist.com/article/mg22029380.700-lifes-purpose-can-animals-guide-thei...

QUOTE: Jablonka thinks the evolution of associative learning may have been what sparked the Cambrian explosion, the relatively sudden burst of diversification that produced almost all of today's animal phyla about 550 million years ago. If she is right, then we owe almost everything - from the diversity of animal life to human culture - to the ability of organisms to direct evolution towards useful ends.-This article appeared in print under the headline "Life's purpose"-This and the quote below are worth noting for two reasons. 1) You think God's purpose was to create humans, though you refuse to speculate on why he would want to do such a thing. Here we have the proposal that the organisms themselves direct evolution towards useful ends - which I summarized earlier as survival and improvement. An end in itself.-QUOTE: 
Gambling on evolution
Might organisms be able to order up mutations, exactly when they need them? The idea is far from proven, but not as far-fetched as you might think.-2) Perhaps, then, I am not alone in thinking that organisms might possess an inventive mechanism which enables them to innovate. As your own quotes show, the article does not go that far, and still clings to random mutations as the main supplier of innovation. But the above is clearly heading in the direction of my hypothesis. We simply don't know the extent of control that cells/cell communities have over their own development.


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