Whoa! Whoa! dhw take notice!!! (The limitations of science)

by xeno6696 , Sonoran Desert, Saturday, April 19, 2014, 04:39 (3659 days ago) @ David Turell


> > Matt:My perspective when I wrote that was this: Without the filter... there is no observable change. No observable change means stasis. Before we can start explaining differences--the differences have to be manifest!
> 
> But that is an necessarily active part. Epigenetic changes, mutation, genetic drift, all active processes produce variety. Then natural selection, up to that point passive, comes into action to produce choices. 
> 
> > Matt: I think a basic analogy works: Picture a bowling ball at the top of a ramp. Without an initial force or bump... there's nothing to make the ball roll down the hill. 
> > 
> > Imagine a device that sits under the ball and keeps increasing elevation. That's your genetic changes collecting. WIthout an initial force to knock it down the ramp, the system is simply gaining potential energy... but its never going to use any of it without a nudge. In this analogy, the nudge is natural selection.
> 
> Your analogy doesn't work. It is simply exactly parallel to my description. The devise is actively raising the ball (making varieties) and the nudge is natural selection, having been presented variety while it sits passively by, now can act on the varieties and become active. It is a two step process. Natural selection never creats variety.-I'm confused. Because you agree with me, except you don't...-Let me focus here: 

Natural selection never creats variety.-Yes it does: It is responsible for forcing organisms to adapt. That means precisely that variety doesn't come into tangible fruition, without selection. And my analogy was absolutely perfect: you agreed to it exactly... but didn't! -Simple case: Asteroid crashes into the earth. THAT is the impetus that then FORCES organisms into rapid adaptation. My position 3 years ago, and in this case, as it is now--is that you can have ALL the epigenetic and random neutral/good mutations going on that you want. But those changes rarely result in observable phenotypes. (I'm leaving room for "simple" changes such as fur color/eye colour/size variations etc.) -But if an event never happens that puts pressure against those alleles, evolution does not happen! This echoes a previous post, where I stated to prove that epigenetics is a stronger source of evolutionary change, you needed to be able to demonstrate that an organism exhibits enough of a change as to be called a different species, without the presence of selective pressure. -Maybe a football (soccer) analogy is in order: Natural selection is the goalie. It doesn't matter at all what happens on the other side of the field, except in the ultra-rare instances when the ball gets past the goalie.

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\"Why is it, Master, that ascetics fight with ascetics?\"

\"It is, brahmin, because of attachment to views, adherence to views, fixation on views, addiction to views, obsession with views, holding firmly to views that ascetics fight with ascetics.\"