Questions of Natural selection

[Confused]

At the end of Why Darwin Matters: A case against intelligent design, the author, Shermer, raises some interesting issues with Natural Selection. These will naturally be the issues for debate:

1) If natural selection is the primary mechanism of evolution, what is the role of chance and contingency in the history of life?

2) What is the target of Natural Selection: the individual organism; or the lower levels of genes, chromosomes, organelles, and cells; or the higher level of groups, species, etc.. Why?

[Confused]

ST88:

And not to be picky (or tacky) but viruses have RNA, not DNA

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At what junction did I say that viruses have DNA? I simply put forth how viruses can use DNA.

ST88:

But irrespective of the appendix, the larger point is that it is still mutation that will get rid of it. Just because we don't need it doesn't mean it will go away. There has to be some kind of valid reproductive advantage to not having it.

Perhaps I am getting a bit confused here. Are you saying that mutations that occur that "phase something out" have to have some kind of valid reproductive advantage to not having it? There is no randomness to it? Perhaps I have been on rotation to long and need a bit more sleep. I think between you and QED, the past 24 hour rotation has sucked.

[Confused]

Cephus:

There is no 'target' for natural selection. You're trying to impose meaning and purpose on a purely natural phenomenon. Natural selection has no intelligence, it has no purpose, it has no goals. Mankind was never planned, we just happened. We're not special and I think that's what most theists have a problem understanding.

I don't know that I would call natural selection a purely natural phenomenon. Equating a response for survival with natural isn't always true. For example, if food sources diminished dramatically, those with a slower metabolism would likely survive longer than those with a faster metabolism (take that all you supermodels). Was it natural selection that dictated this, or what it simply by chance that some people have a slower metabolism than others which allowed them to conserve energy longer? I am not trying to say that mankind is special in any way. I am not trying to say that man was planned. I am questioning where evolution is going, to a degree.

[Furrowed Brow]

Cephus:

There is no 'target' for natural selection. You're trying to impose meaning and purpose on a purely natural phenomenon. Natural selection has no intelligence, it has no purpose, it has no goals. Mankind was never planned, we just happened. We're not special and I think that's what most theists have a problem understanding.

I don't know that I would call natural selection a purely natural phenomenon. Equating a response for survival with natural isn't always true. For example, if food sources diminished dramatically, those with a slower metabolism would likely survive longer than those with a faster metabolism (take that all you supermodels). Was it natural selection that dictated this, or what it simply by chance that some people have a slower metabolism than others which allowed them to conserve energy longer? I am not trying to say that mankind is special in any way. I am not trying to say that man was planned. I am questioning where evolution is going, to a degree.

I think we have to be careful not to assert that behaviour or characteristic has been selected "for". Natural selection selects against. Look at this way, all behaviour etc is a mutation nature has not yet deemed fit to eradicate.

[QED]

I think Cephus hit the nail on the head when he reminded us that natural selection is only provident for us up until the time when we have gotten as far as reproducing to some critical degree. Anything that gets in the way of that first blush of procreation will be right in the firing line for adjustment, but from then on the natural economics of population density take over. Little wonder we lose our "pixie appeal" all too soon.

When we ask questions like "where is evolution going" I think the most appropriate answer would be "everywhere it can". It needn't be smarter or dumber, bigger or smaller. Anything at all that can keep its head above the waters of extinction has satisfied the logic of natural selection and nothing else that I can think of has any bearing.

[Cephus]

I don't know that I would call natural selection a purely natural phenomenon. Equating a response for survival with natural isn't always true. For example, if food sources diminished dramatically, those with a slower metabolism would likely survive longer than those with a faster metabolism (take that all you supermodels). Was it natural selection that dictated this, or what it simply by chance that some people have a slower metabolism than others which allowed them to conserve energy longer? I am not trying to say that mankind is special in any way. I am not trying to say that man was planned. I am questioning where evolution is going, to a degree.

It's not "going" anywhere, it just is. And of course it has to be natural, otherwise it wouldn't be "natural selection", it would be "artificial selection". By definition, natural selection has to be natural.

[Cephus]

When we ask questions like "where is evolution going" I think the most appropriate answer would be "everywhere it can". It needn't be smarter or dumber, bigger or smaller. Anything at all that can keep its head above the waters of extinction has satisfied the logic of natural selection and nothing else that I can think of has any bearing.

The answer is, natural selection isn't "going" anywhere. It has no plan. It has no purpose. What happens, happens. Natural selection simply provides raw material and what happens with that raw material simply happens without guidance or purpose. Extinction doesn't matter. Improvement doesn't matter. Nothing matters except putting out a variation in the genes and the best man wins.

[QED]

When we ask questions like "where is evolution going" I think the most appropriate answer would be "everywhere it can". It needn't be smarter or dumber, bigger or smaller. Anything at all that can keep its head above the waters of extinction has satisfied the logic of natural selection and nothing else that I can think of has any bearing.

The answer is, natural selection isn't "going" anywhere. It has no plan. It has no purpose. What happens, happens. Natural selection simply provides raw material and what happens with that raw material simply happens without guidance or purpose. Extinction doesn't matter. Improvement doesn't matter. Nothing matters except putting out a variation in the genes and the best man wins.

Sure, of course there's no plan as the whole mechanism is adaptive and opportunistic. Yet it's still a process. It's something that atoms can't help but do as far as I can see. Now that certainly doesn't give licence to anthropocentric notions like guidance or purpose but the process does work within a framework which characterizes the products. For instance, i would say that Colonization is a result of the process rather than an aim (just try keeping something sterile for any length of time!) but people will argue that that's God's whole plan for things. How do you counter that?

[Cephus]

Sure, of course there's no plan as the whole mechanism is adaptive and opportunistic. Yet it's still a process. It's something that atoms can't help but do as far as I can see. Now that certainly doesn't give licence to anthropocentric notions like guidance or purpose but the process does work within a framework which characterizes the products. For instance, i would say that Colonization is a result of the process rather than an aim (just try keeping something sterile for any length of time!) but people will argue that that's God's whole plan for things. How do you counter that?

It's a process, but it's one without a recognizable or predictable next step. It follows well-defined and well-understood rules and something grows out of it. What that something might be isn't predictable. I make this distinction because theists want to use it to say that humanity was predestined to exist and that's simply not true.

Of course, once you get people arguing that it's "God's plan", they've just lost the argument, they need to demonstrate that God exists, has a plan and that they understand what that plan might be. If they fail to do those three things, then they have no part in a rational, intellectual debate.

[honegod]

What is the target of Natural Selection: the individual organism; or the lower levels of genes, chromosomes, organelles, and cells; or the higher level of groups, species, etc.. Why?

if there is a plain with an eaven mixture of two different kinds of rocks, one is hard and resistant to sunlight, the other is soft and dissolves into atoms when subjected to sunlight, and you subject the plain to sunlight for a long time, the plain will eventually only have the hard rocks on the surface.

that is natural selection. the hard rocks have been "selected" to be on the surface.

so the answer to the question is "all of them."
where there is a reaction to something that varies that variation creates selection.

[QED]

It's a process, but it's one without a recognizable or predictable next step. It follows well-defined and well-understood rules and something grows out of it. What that something might be isn't predictable. I make this distinction because theists want to use it to say that humanity was predestined to exist and that's simply not true.

Without any supernatural dimension the process would be (and is!) a cellular automata albeit a highly complicated (i.e. chaotic) one. But doesn't that mean that we could, in principle, calculate the appearance of humanity from initial conditions of the universe? This would seem to bring us back to the vexed question of the uncertainty principle, hidden variables etc.

Of course, once you get people arguing that it's "God's plan", they've just lost the argument, they need to demonstrate that God exists, has a plan and that they understand what that plan might be. If they fail to do those three things, then they have no part in a rational, intellectual debate.

But surely they would be entitled to say that God might exist, and might have a plan etc. Where the rational intellectual debate ought to be focused in my opinion is upon why any unsupported, dogmatic, assertion should be the basis for political action that inflicts needless harm on people.