Craig's Science topics: #1. Evolution of complex features

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Craig234

Lifer
May 1, 2006
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Let's speculate that in 5,000,000 years, there is a type of animal that developed an extremely thick fur, thicker than any animal fur (bear, cat etc.) we know today. This COULD have evolved in 5M years due to a new ice age and a colder planet. <-- mind you this is only speculative for the sake of this discussion.

TODAY, however, animals have normal fur, and even DESPITE them having fur, animals need warmth to survive, or like a bear need to go into hibernation to survive the winter. These hypothetical animals with the "extremely thick fur" wouldn't need it, they could even survive the coldest cold.

Does this make today's fur "not nearly as useful"? Would you then say that today's fur is sort-of useless, because it cannot 100% protect animals from the cold, like the hypothetical fur that could evolve in some millions of years?

That's a false analogy. In one case, the fur has adapted to a changed environment - which fits the theory fine. But animals with half-developed wings didn't 'fit the environment' then with their non-flight. If in 5 million years birds develop lasers on their wings, great, but the wings still made sense now. Not so much the forming wings.
 

Craig234

Lifer
May 1, 2006
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Yes, indeed, so-called "irreducible complexity" is an argument that proponents of "intelligent design" (a.k.a. creationism) make against evolution. It was center stage in the trial documented in this NOVA episode:

https://www.youtube.com/watch?v=7HZzGXnYL5I

If you haven't seen it, IMHO it's worthwhile use of two hours. The snippets most directly dealing with the "irreducible complexity" issue are 0:39 to 0:47 and 1:05 to 1:15.

I'm regularly astounded by the willingness of many people to reject the best scientific explanations just because they are somehow in conflict with what they (on the basis of very little knowledge) judge to be possible.

As an example, all the evidence points to the conclusion that the ancient Egyptians built the pyramids -- even though their construction methods are still a matter of considerable debate. It boggles the mind that some people cite this uncertainty over their construction methods as a reason to leap to the conclusion that the Egyptians couldn't have built them by themselves -- they must have had help from aliens! Which seems more likely? That archeologists can still learn a thing or two from the ancient Egyptians, or that aliens crossed interstellar space to stack granite blocks in the desert?

Along these same lines, which seems more likely? That we still have a thing or two to learn about how evolution works, or that there must be an omnipotent "intelligent designer" assembling species after species?

it has come up there as well. I think I saw the NOVA show years ago, but will check that again, thanks for linking it. Both your pyramid analogy and your interpretation of my post are incorrect, though.

The Pyramids definitely fit in the 'how in the world did they do that, but I'm sure there is a plausible explanation' area. If we found the Empire State Building with all the modern design among
the pyramids, THEN I'd start asking about aliens. Similarly, it seems there must be some explanation for the evolution of the wings - but I said I don't know what it is. That's not aliens.
 

Craig234

Lifer
May 1, 2006
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NOVA show was fine. It devastated the Creation Science issues, and debunked the examples they had questioning how evolution made some jumps. The show didn't really cover more complex
features that well - they just got a mention for the most part, though the transition of one animal was documented form sea to land.
 

PowerEngineer

Diamond Member
Oct 22, 2001
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I glad that you liked the NOVA program.

My "pyramids" analogy was aimed at people to reject the best scientific explanations on little better than a whim, and I'll stand by it. Please note that I did not say that I knew you were one of those people. If the shoe doesn't fit, I'm not going to make you wear it! :p

With few exceptions, people who have started threads with an original post about "irreducible complexity" have turned out to be faith-driven "intelligent design" believers. It's therefore understandable that an original post like yours may lead some regular posters to react to it as if it is the opening salvo of your attack on evolution.

On the issue, let me suggest that evolution only works over very long periods of time. Mutations that are only "slightly harmful" do not get cleansed from the gene pool in just a generation or two, and "roughly neutral" mutations can get carried forward indefinitely. Some mutations may be helpful or harmful based on outside factors (sickle cell as an example). And changing conditions may transform what was a "roughly neutral" mutation into a "very helpful" (or "very harmful") one. I think it would be a mistake to think that any organism is fully optimized by the forces of evolution; it's a ongoing, very rough optimization in which only the "very helpful" or "very harmful" mutations are rewarded or punished over time.

To my way of thinking, this opens the door to an organism carrying forward over many generations a lengthening string of slightly helpful/harmful mutations until at last a final mutation turns the entire string into something that's very helpful (like a bird wing).

Just a thought...
 

flexy

Diamond Member
Sep 28, 2001
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But animals with half-developed wings didn't 'fit the environment' then with their non-flight.

Whatever evolved and stayed and then carried over definitely fit the environment and fulfilled *some* purpose. And this includes interim steps.
 

SMOGZINN

Lifer
Jun 17, 2005
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complex features

There is no such thing as a complex feature. All so called complex features are simple features added together. The wing is a specialized arm, the arm is a specialized leg, the leg is a specialized flipper, the flipper is a specialized pseudopod, the pseudopod is just a longer than normal bump. All of these things had some utility and can be seen in nature today. There are creatures with wing like structures that can't fly. Another interesting thing to note is that not all birds fly the same way, a hummingbird and an albatross have very different types of wings that work differently. So obviously they are not irreducible.
 

agent00f

Lifer
Jun 9, 2016
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Creatures with half-developed brains didn't 'fit the environment' with their non-sense. Brain make all kinds of sense if someone was saying "we want the ability to think, to let's invent brains". But there was no one saying that. Just animals randomly mutating.
 

Craig234

Lifer
May 1, 2006
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PE, thanks for your post, I generally agree with it - but the argument on the wing, just doesn't fly yet.:) That's a hell of a complicated feature to stumble along with 'random mutations' slowly moving toward that without any purpose for the interim stages until suddenly, "hey, at our last wing flapping party, Chuck went in the air! What the heck!"
 

Craig234

Lifer
May 1, 2006
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Whatever evolved and stayed and then carried over definitely fit the environment and fulfilled *some* purpose. And this includes interim steps.

That's a nice assertion, and deductively is strongly suggested.

But I'd like to better understand what some of these purposes that fit the natural selection theory are for a lot of complex features. Wings are just a good example.

That NOVA documentary, which I remember as the best I've seen on the topic of Creationism from some time ago, debunks some cases people wrongly thought posed a challenge.

But there are a lot more that aren't clear, but presumably have an answer.
 

Craig234

Lifer
May 1, 2006
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There is no such thing as a complex feature. All so called complex features are simple features added together. The wing is a specialized arm, the arm is a specialized leg, the leg is a specialized flipper, the flipper is a specialized pseudopod, the pseudopod is just a longer than normal bump. All of these things had some utility and can be seen in nature today. There are creatures with wing like structures that can't fly. Another interesting thing to note is that not all birds fly the same way, a hummingbird and an albatross have very different types of wings that work differently. So obviously they are not irreducible.

Let's look at your claim.

First, there is such a thing as a complex feature. Too many examples to bother listing. And let's say the wing is one, because things like the hollowed bones, the feathers in an arrangement, the wing of the right size for flight, the muscles for flying - all are components of the very useful ability to fly, but which become useful once the ability to fly is there, not so much before that.

So let's take your claim of 'the wing is a specialized arm'. Presumably that'd make some sense. But how many evolutionary steps do you think it'd take for an arm to start mutating the features of a wing, when it's not clear how those features are better able to survive, all the while not flying, just going more and more towards a flying wing, until finally it is a flying wing?

With this issue still muddy, I'm going to add an aspect to the topic. The idea that some species seem to evolve less over time and others more.

Some species haven't changed a lot - but have evolved some - in hundreds of millions of years, while species like humans, cats and dogs have changed hugely much faster.

A factor biologists cite for little-changing species is ones that don't have much to compete with in their environment.

This would suggest to the topic someone raised about 'birds in 500,000 years' that they may or may not change much.
 
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PowerEngineer

Diamond Member
Oct 22, 2001
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PE, thanks for your post, I generally agree with it - but the argument on the wing, just doesn't fly yet.:) That's a hell of a complicated feature to stumble along with 'random mutations' slowly moving toward that without any purpose for the interim stages until suddenly, "hey, at our last wing flapping party, Chuck went in the air! What the heck!"

Well, clearly this hinges on how well you and I judge what's likely to occur through random mutations, and our judgments are shaped as much by experience as by rational thought. As humans, the random "mutations" we experience usually involve a relatively small number of possible outcomes, such as the rolls of die or the ordering of cards in a shuffled deck. And we are usually dealing with a relatively small number of trials. Our "common sense" expectations may not hold up well when extrapolated into the much larger numbers we confront when looking at random genetic mutations over evolutionary time frames.

As an example, the odds of rolling "box cars" (with two die) eight times in a row is roughly 1 in 430 million attempts. Our first thought is that the result is therefore virtually impossible. But another way of looking at the same odds is that it is virtually certain that two people will get that result if a billion people make the attempt. Similarly, a very improbable string of random mutations that result in wings may come to pass because of the huge number of trials through generations of reproduction spanning millions of years.

And lucky Chuck's wings are the death knell for his less lucky flapping party friends. Like a lit match starting a forest fire, his wings confer a dominant survival advantage that quickly spreads to dominate his specie's gene pool.
 

cbrunny

Diamond Member
Oct 12, 2007
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PE, thanks for your post, I generally agree with it - but the argument on the wing, just doesn't fly yet.:) That's a hell of a complicated feature to stumble along with 'random mutations' slowly moving toward that without any purpose for the interim stages until suddenly, "hey, at our last wing flapping party, Chuck went in the air! What the heck!"
Do you make the assumption that the same organism that could not fly "evolved" into one that can? You know Pokemon isn't real, right? They'd be a different organism.

Put it another way, at Chuck's wing flapping party, no one could fly. Everyone at the party eventually died and at their children's children's children's children's first ever wing flapping party, Chuck the 5th flew and all his buddies did not. Then eventually all of Chuck the 5ths friends were eaten by a crocodile or whatever but Chuck the 5th got away because he can fly. Chuck the 5th's two children could fly, and their two children could fly, and their two children could fly, and each time the croc came around they flew away but their not-flying capable buddies got crunched up and eaten.
 

Craig234

Lifer
May 1, 2006
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The bird that can fly evolved from something - and it probably wasn't a dog. The issue here is why the 100,000 mutations or whatever it took to get from a that couldn't fly to one that could, kept mutating things toward flight when the partial progress did not allow flight and therefore doesn't fit natural selection much unless there was other benefit to each that's not clear at all.
 

cbrunny

Diamond Member
Oct 12, 2007
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Because you don't understand natural selection.

Something that is useless did not necessarily mean it was not continued or that whatever species that had it would go extinct.
 

Dr. Zaus

Lifer
Oct 16, 2008
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Of course it is, it doesn't pretend to be anything else. That was my point.

Like the word "how", the word "why" also has several different, if vaguely related, meanings.. The way you used it in that sentence doesn't mean "wherefore", as in a metaphysical explanation for the fundamental existence of something (or for that matter "everything"), it means "in what way" (or in other words, "how"...)
I disagree. On the level of physics even "wherefor gravity..." is an explanation of an observation of how. Just as in social psychology "wherefore regression to the mean..." ecplanes why some empirical how occurred.
These are explanations of why something happens. How is empirical, why is an artifact of our mind's ability to organize the empirical world.

The theory of evolution is an explanation of how: "adaptive changes" and why: "because adaptive change are a probabilisticly nesseary outcome of random changes."
 
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agent00f

Lifer
Jun 9, 2016
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I disagree. On the level of physics even "wherefor gravity..." is an explanation of an observation of how. Just as in social psychology "wherefore regression to the mean..." ecplanes why some empirical how occurred.
These are explanations of why something happens. How is empirical, why is an artifact of our mind's ability to organize the empirical world.

The theory of evolution is an explanation of how: "adaptive changes" and why: "because adaptive change are a probabilisticly nesseary outcome of random changes."

The way you're insisting on absolute definitions for human language here isn't much than the way OP insists chickens can't exist.
 

Craig234

Lifer
May 1, 2006
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Because you don't understand natural selection.

Something that is useless did not necessarily mean it was not continued or that whatever species that had it would go extinct.

Uh, why don't you provide evidence for your definition of natural selection for some feature developing in one direction over thousands of mutations that are useless. Might be you not understanding what natural selection is. And I didn't say anything about going extinct.
 

cbrunny

Diamond Member
Oct 12, 2007
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Uh, why don't you provide evidence for your definition of natural selection for some feature developing in one direction over thousands of mutations that are useless. Might be you not understanding what natural selection is. And I didn't say anything about going extinct.
lol male nipples.

I'm not really sure what you're getting at. "my definition" of natural selection is the definition of natural selection.

Yours seems to be based on a 50/50 chance of life or death on any given mutation or some such thing. I'm not even sure, to be honest.
 

Craig234

Lifer
May 1, 2006
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lol male nipples.

I'm not really sure what you're getting at. "my definition" of natural selection is the definition of natural selection.

Yours seems to be based on a 50/50 chance of life or death on any given mutation or some such thing. I'm not even sure, to be honest.

No, you both misstate my position and fail to provide any evidence for your definition or to even say it clearly.
 

agent00f

Lifer
Jun 9, 2016
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Uh, why don't you provide evidence for your definition of natural selection for some feature developing in one direction over thousands of mutations that are useless. Might be you not understanding what natural selection is. And I didn't say anything about going extinct.

It would be to your own benefit to consider if you might be wrong and the people who know more about this are right. There's apparently a wiki page about this very topic with numerous citations to what legit experts think.
 

Dr. Zaus

Lifer
Oct 16, 2008
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The way you're insisting on absolute definitions for human language here isn't much than the way OP insists chickens can't exist.
Im just explain img how social science defines the terms: I'm happy to hear about other word games with different axioms. However, I would like to know whose axioms they are: your own personal language isn't much use.