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Dover Penn ID trial

Melendwyr said:
Natural selection does apply to all of those situations. Evolutionary biology, however, is only concerned with natural selection as it applies to living organisms - it makes no statements about the origins of life or the existence of matter.
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What definition of natural selection are you using? Certainly not any that I am familiar with. Darwin's summary is:
IF there are organisms that reproduce, and
IF offspring inherit traits from their progenitor(s), and
IF there is variability of traits, and
IF the environment cannot support all members of a growing population,
THEN those members of the population with less-adaptive traits (determined by the environment) will die out, and
THEN those members with more-adaptive traits (determined by the environment) will thrive

So...I don't see how this can possibly apply to the beginnings of the universe, the formation of stars, metals, etc., or even to abiogenesis. Only after these things have happened can we possibly have the IF conditions which define natural selection.

I look forward to your explanation.
 
Upchurch said:
How so? Natural selection works through the subject being able to reproduce (or not, as the case may be) and pass along its genetic material.
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As in, for example, the birth of stars from the remnants of previous stars.

I wouldn't use the term natural selection for this, just because it causes confusion with a term that already has the world confused. But it's something similar to selection. I'd also avoid using the term evolution in other contexts.

~~ Paul
 
Upchurch said:
How so? Natural selection works through the subject being able to reproduce (or not, as the case may be) and pass along its genetic material.
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No, it doesn't. Natural selection is really only concerned with the persistance of arrangements - biological reproduction is only an particular example of the more general principle.
 
Melendwyr said:
No, it doesn't. Natural selection is really only concerned with the persistance of arrangements - biological reproduction is only an particular example of the more general principle.
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So, a completely different definition than Darwin's.
 
Mercutio said:
So, a completely different definition than Darwin's.
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Or anyone else's, for that matter, since it completely leaves out the mechanism in natural selection that interrupts "the persistance of arrangements".

Or is extinction not a part of natural selection?
 
Hold on! I agree that the term natural selection is confusing and misleading here.

But there certainly are selection pressures for events other than biological ones. Here's one: There is significant pressure for a trickle of water to follow depressions in the ground rather than small hillocks. Another: There is pressure for a planetoid to end up in certain orbits around its sun. How about: There is pressure for mountains to appear where tectonic plates are compressing.

Or is extinction not a part of natural selection?
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In all the cases I cited above, certain objects disappear if they do not happen to "follow the pressure."

~~ Paul
 
What I noted was the very first sentence of the cartoon:

Once upon a time, there was a complete void in space.
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I'm not aware of any currently supported theory that includes this. Any that I have heard of make it quite clear that time, space, and matter are all related. Time could not exist without the other two, therefore there was no time before the existance of matter.

It's just bad form to begin any point with a faulty model of the opposing view. I believe there's a word for that, starts with a straw- and ends with a -man :)
 
Paul C. Anagnostopoulos said:
Hold on! I agree that the term natural selection is confusing and misleading here.

But there certainly are selection pressures for events other than biological ones. Here's one: There is significant pressure for a trickle of water to follow depressions in the ground rather than small hillocks. Another: There is pressure for a planetoid to end up in certain orbits around its sun. How about: There is pressure for mountains to appear where tectonic plates are compressing.


In all the cases I cited above, certain objects disappear if they do not happen to "follow the pressure."

~~ Paul
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I think you might be misapprehending pressure in this context. Living organisms do not conform by being beaten down, as in water in a graviational field or pebbles being rounded.

Living organisms persist only if they can continue to accrue energy. The original competition was in who could actually reproduce, and at that time the only energy was in other organic molecules. The original was chemical evolution by sustained reaction. The more molecules that accrued, the more chance of persisting; rather the antithesis of rocks being beaten down. It would be as if rough rocks had a better chance of washing downstream; you would end up with more rough rocks than not in a given environment. The rounding is not a selection pressure; the differential is.

Now, this is not to say sedimentation is evolution; it represents a selection pressure. A sieve in sand is similar in this regard, as there are some grains that get past while some do not. But this is only part of the equation; it is selection pressure, it is not evolution. Evolution comes about when there is more than one molecule vying for available energy as a means of survival. The larger ones persist, then the ones that can fold so they are harder to break apart, then the ones of those that can more efficiently fold and unfold with temperature changes to both guard and assemble more energy. Eventually, some have folding sequences that curve and actually cover other sequences during vulnerable times, or that form a ribozyme that clips at other sequences (the first predator).

From there it is steps along the way, with selection pressure being the gate, but mutation and reproduction being the driving force to create a new generation. Without change, a new selection pressure could cause an end to this process. Without reproduction, the process stops.
 
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Mercutio said:
Ok, it does not really belong here, but nowhere else either...I am so pissed off at my local paper. Today's editorial cartoon?


dickwright.gif



So...does my paper now openly advocate ignorance?
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They left out the last line: "That one REALLY shows my total ignorance!"
 
PatKelley said:
I think you might be misapprehending pressure in this context. Living organisms do not conform by being beaten down, as in water in a graviational field or pebbles being rounded.
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Well, the ones that can't see above themselves are beaten down by falling rocks, right? Yes, I understand that "selection pressure" does not mean physical pressure.

~~ Paul
 
Mercutio said:
So, a completely different definition than Darwin's.
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(raises eyebrow) Darwin was addressing the subject of change in biological organisms. Not surprisingly, he was concerned with selection pressures that operate on biological organisms.

Nature exercises selection in other ways that reproduction and (biological) competition, too.
 
I gave several examples above. We are not saying that other forms of selection are exactly the same sort of thing as biological natural selection, but they are forms of pressure and selection. Dust and rocks in the appropriate orbits are selected to become planetoids. The other dust stays dust. Water that follows depressions collects into rivulets and then streams. The other water simply evaporates. The right sort of crystals replicate; the rest crumble apart.

It must be the case the non-life undergoes pressure and selection, or life would not have gotten started in the first place.

~~ Paul
 
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