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Blight

Social climber
Oct 26, 2006 - 05:28am PT
All my own work, Raymond, but I doubt that I'm the only person who's thought all this.
raymond phule

climber
Oct 26, 2006 - 05:33am PT
Many people in this thread have claimed that you don't seem to understand evolution and that is the reason that you cant find your evidence. Dont you even think for a second that those people might actually be right? That your problem with the theory exist because you doesn't understand it?
Blight

Social climber
Oct 26, 2006 - 06:14am PT
Yes, of course!

However, since nobody has shown that I don't understand what's being dicussed, and my objections are not directed at complex scientific principles but at common sense, it seems unlikely.

No rational person ever considers themselves to absolutely 100% correct, you're right there.

Do you consider it possible that evolution as currently described is incorrect?
raymond phule

climber
Oct 26, 2006 - 07:30am PT
"However, since nobody has shown that I don't understand what's being dicussed"

Shown is relative, some people probably think that they have shown it to you. You can prove E=MC^2 in the best possible way to a two year but is not going to understand that you have proved it.

I dont belive that there are any real expert on evolution here on supertopo so theirs opinion is not that important according to me. Why dont you ask some scientist working on evolution? There are probably forums that discuss this.

"and my objections are not directed at complex scientific principles but at common sense, it seems unlikely."

You talk about mutations and seem to have a different understanding of what a mutation is and what evidence is necessary. Mutations and DNA is definitely not common sense.

"Do you consider it possible that evolution as currently described is incorrect?"

It depends on what you mean with that evolution is correct. In large I belive that it is correct but some mechanism could be missunderstod. I am not in a situation that I really could decide if it is correct or not in the same way as I cant look at the evidence for the relativity theory and decide for or against. I dont have the knowledge that is necessary right now. I have to belive the expertize in the field. All people that I have seen is opponents of evolution have had a religious agenda to show that it is incorrect. It hasn't been difficullt to decide who have belive most.
Blight

Social climber
Oct 26, 2006 - 07:59am PT
Why dont you ask some scientist working on evolution?

I have. Several of my friends are doc and post doc students who are working or have worked in the area. But you can never test your ideas thoroughly enough, so I ask again and again. This thread has shown me many new views and sources, it's been great.

In large I belive that it is correct but some mechanism could be missunderstod.

That's exactly what I believe. The broad sense of it looks pretty hard to dispute, but the details? I'm not convinced we've got it right yet, and as long as we keep assuming that we have, no new investigation can progress.

All people that I have seen is opponents of evolution have had a religious agenda to show that it is incorrect.

Really? I've seen plenty of scientists question it too. Personally, I don't have an alternative to offer. Creationism and Intelligent Design have just as many if not more problems than evolution, which kind of leaves me in limbo for now.
Aya

Uncategorizable climber
New York
Oct 26, 2006 - 08:01am PT
Here's an analogy: our immune system contains cells which have the ability to adapt to combat foreign bodies they've never encountered before. Is this evolution? Of course not, these cells have a preexisting mechanism which allows them to make superficial changes in response to their environment.

So to return to the nylon-eating bugs: I don't accept the ability to eat nylon instead of carbohydrates as evidence of evolution for the same reason; it's just the superficial result of a preexisting mechanism, not a new mechanism itself.


This is not an apt analogy. The process by which immunoglobulins are able to rearrrange their antigen binding regions to recognize new antigens (VDJ recombination) is understood (and as a total and irrelevant aside, initially elucidated by my father!). This is not evolution and nobody is claiming it is, particularly, because as you state, it is a superficial change in response to the environment (although it is analagous in that the Igs which do not rearrange to recognize the novel antigen are not replicated, and it is the ones that do which are). It happens within the individual, rather than across generations - just because my mom is immune to chicken pox does not mean that I will be. This is of course the core of evolutionary theory: descent with modification.

In the case of the bacteria, the ability to digest nylon did not already exist. It doesn't exist in other bacteria. As in, you can take them and put them on nylon, and they can't digest it.

A mistake in DNA replication when an individual bacterium was reproducing happened to shift a bit of the parent bacterium's DNA such that its offspring suddenly had DNA that coded for a protein that digested nylon.

I'll repose a question you did not answer:
It seems to me that you're saying that this was not new because the mutation that allowed it to happen was a frameshift mutation: yes or no?

And if yes, then I guess that's what you need to further learn about, because that's where the problem lies.

If no: Please describe exactly and precisely what the "pre-existing mechanism" for digesting nylon in the parent bacterium was.

Please describe to me what, exactly, it was that allowed the offspring to do something that its parent could not.

Ones which are new. Not seen before. A new limb, a new organ, a new trait. Something novel, sustainable, net positive and possible without interference. Evolutionary theory says such things arise. So why is there no evidence of this happening?

I've been giving it to you, but you seem to be dismissing novel traits due to either a lack of desire to understand or a lack of ability understanding of the examples I'm giving you. I'm hoping it's the latter, which is why I've been spending the time to try to break things down for you and show you how your statements are flawed.

I don't dismiss the idea that mutations arose in the bacteria's genome. I dismiss the idea that this is a new trait.

If it is not a new trait, what is it?
Yes, the bacteria were able to originally survive at a range of temperatures. You agree that there were mutations that arose in the bacterial population, some of which allowed them to survive better at the new temperatures than the original bacteria.

We return to the crux of the problem, then, and why you will evidently never accept evolution: what you are asking for is not something that you can reasonably expect to witness within your lifetime: a new limb or organ is an incredibly complex thing, and you simply will not live long enough to see them all the necessary mutations accumulate. What I am offering you is an example that you can witness: sequenced, identified, new changes in DNA which confer upon their carriers the ability to survive in novel environments better than their parents. This is the fundamental definition of evolution: descent (the subsequent generations) with modification (a change in the genome).

A good example of natural selection. Of course the genes in surviving organisms were passed on looking for.

Looking for what? The genes in the surviving organisms were passed on, yes. Where did they come from?

No. I have little interest in DNA sequences because you know as well as I do that they're not fixed, even within an organism. I'm looking for sustainable evidence of the results of new DNA: a new organ, limb or trait as described above.

If you're genuinely interested in finding convincing examples of evolution, you should be interested in DNA, as it is the mechanism by which changes are transmitted from generation to generation. It is why we know that the pathway by which lactose was digested in Barry Hall's bacteria was new.

Eating is not a new process, as I've said before.

Eating nylon is new.

By extension then, you'd dismiss an example of a dog with wheels instead of legs, because locomotion is not new? You'd dismiss a cat which breathed nitrogen instead of oxygen, because breathing is not new? You'd dismiss a mammal which reproduced by getting wet (just be sure not to feed after midnight), because reproduction is not new?
Aya

Uncategorizable climber
New York
Oct 26, 2006 - 08:09am PT
raymond - I am (was) a scientist and I did work at least peripherally, on evolution in a past life, such as the evolution of resistance (and its subsequent loss, which is also revolution) to heavy metals in worms in the Hudson. As I mentioned before, my personal research was more focused on the ecology side of the equation, but I think I do sort of fit your general criteria....
TradIsGood

Fun-loving climber
the Gunks end of the country
Oct 26, 2006 - 08:09am PT
Blight, 100 posts after I suggested it, perhaps it is time that you actually posted what you believe the theory says, rather than objection after objection.

What the theory says. Not your ideas of valid tests.

Show a little of that rigor to which so far, I claim, you only pretend to. Prove my claim wrong! :-)
Blight

Social climber
Oct 26, 2006 - 09:09am PT
A mistake in DNA replication when an individual bacterium was reproducing happened to shift a bit of the parent bacterium's DNA such that its offspring suddenly had DNA that coded for a protein that digested nylon.

Also, the bacterium lost the ability to digest carbohydrate.

This is my point (or rather, an extension of it): just swapping traits around can't result in organisms becoming more complex. As such, it could hardly be evidence of the evolutionary development we're looking for.

you seem to be dismissing novel traits due to either a lack of desire to understand or a lack of ability understanding of the examples I'm giving you.

So again, if I disagree with you, I must be wrong? With respect, you have a remarkable degree of faith in your own brilliance. Do you consider it possible that you could be wrong?

If it is not a new trait, what is it?

A modification of an existing one. If all organisms have the same number of traits generation after generation, no increase in complexity can occur.

We return to the crux of the problem, then, and why you will evidently never accept evolution

I'll accept the mechanism you propose as soon as you show that it leads to the changes hypothesised. If you want to fall back on believing an untestable hypothesis, go ahead. That's your right and I won't judge you for it.
Blight

Social climber
Oct 26, 2006 - 09:16am PT
Blight, 100 posts after I suggested it, perhaps it is time that you actually posted what you believe the theory says, rather than objection after objection.

And as I said to Aya nearly 100 posts ago, perhaps I have some of my terminology wrong. Why don't you tell me what you believe the theory says and I'll see if I need any clarification?

After all, I'm not claiming to be an expert, and I happily admit that I could well be wrong.
TradIsGood

Fun-loving climber
the Gunks end of the country
Oct 26, 2006 - 09:27am PT
Put out your version of the theory in your terminology. You can even define the terms, to be clear.
graniteclimber

Trad climber
Nowhere
Oct 26, 2006 - 09:32am PT
Aya wrote: "By extension then, you'd dismiss an example of a dog with wheels instead of legs, because locomotion is not new? You'd dismiss a cat which breathed nitrogen instead of oxygen, because breathing is not new? You'd dismiss a mammal which reproduced by getting wet (just be sure not to feed after midnight), because reproduction is not new?"

Brilliant! But good luck in making any headway.

Aya, you are a very patient individual.

I like the image of dogs on wheels. Ok, a little google image searching and this pops up:


Proof positive of intelligent design! :-)

Edit:

Evolution in motion:


Blight

Social climber
Oct 26, 2006 - 09:44am PT
Put out your version of the theory in your terminology. You can even define the terms, to be clear.

Okay then

I'll go for: "evolution is a process resulting in heritable changes in a population over time".

How does that look?
TradIsGood

Fun-loving climber
the Gunks end of the country
Oct 26, 2006 - 09:57am PT
Another good start! You have defined a process.

Now what is the theory?
Aya

Uncategorizable climber
New York
Oct 26, 2006 - 10:01am PT
It looks like what I gave you an example of: heritable change (the bacteria can digest nylon/lactose/survive better at higher temperatures, in the exmples I've given you thusfar)in a population over time (eg, in the case of the nylon digesting flavobacteria, since the invention of nylon).

Yes or no?
philo

Trad climber
boulder, co.
Oct 26, 2006 - 10:10am PT
Blighty, the mechanism that you are waiting to see evidence of is not what evolutionary theory is about. We are talking about ongoing recombinations that yield greater survivability not "spontaneous" generation. Spontaneous generation would be mutation not evolution. And the experts in the field of evolution are not trying to cling to DOGMA, they are actively trying to disprove the theory. That is the scientific process. The evidence you seek you will never find because your premise is flawed.

To quote you..."what a lark"!
Blight

Social climber
Oct 26, 2006 - 10:15am PT
*sigh*

I've already said - several times - that I have no problem with the basics of evolution.

What I do have a problem with is that the accompanying proposition - that the above process has produced simple organisms from complex ones - seems to have no direct evidence to support it, and is not in fact supported by what you've posted, excellent though it may be in its own right.

philo

Trad climber
boulder, co.
Oct 26, 2006 - 10:17am PT
I could just as easily, and endlessly, argue that the Earth is flat (and the center of the Universe) since noone will take ME into space to "PROVE" it to ME. And we all know those pictures looking back were just photo-shopped artwork. Troll on big guy troll on!
Aya

Uncategorizable climber
New York
Oct 26, 2006 - 10:25am PT
This is my point (or rather, an extension of it): just swapping traits around can't result in organisms becoming more complex. As such, it could hardly be evidence of the evolutionary development we're looking for.

So now, rather than simply the emergence of a novel trait, you're seeking the emergence of a novel trait which increases "complexity"?

I am not certain that I understand why: the theory of evolution, as utilized by evolutionary biologists, makes no claim at increasing an organism's complexity. It certainly may do so, but its only claim is a heritable change which increases fitness.

So again, if I disagree with you, I must be wrong? With respect, you have a remarkable degree of faith in your own brilliance. Do you consider it possible that you could be wrong?

I am frequently wrong, but I'm hardly dismissing what you're saying simply because you disagree. I'm not even dismissing what you're saying: I'm trying to get you to explain your position better, because I think, from your responses, that there is a fundamental misunderstanding somewhere.

In the interest of elucidating this, I'll repose a question that you didn't answer last time around:

Please describe exactly and precisely what the "pre-existing mechanism" for digesting nylon in the parent bacterium was.

Please describe to me what, exactly, it was that allowed the offspring to do something that its parent could not.


Although, apparently this question is less relevant now because apparently since when they gained this ability, they also lost the ability to digest carbohydrates, resulting in no net increase in complexity, you do not believe this to constitute evidence for one of the mechanisms (heritable change conferring fitness advantages)of evolution.

So, let me ask you to instead answer the same question for the lactose digesting bacteria from Barry Hall's work: what was the "pre-existing mechanism" for digesting lactose in the parent bacterium, and what exactly allowed its offspring to do something that it could not?

A modification of an existing one. If all organisms have the same number of traits generation after generation, no increase in complexity can occur.

This statement is necessarily true. That all organisms have the same number of "traits" generation after generation is not. Ignoring the fact that the development of complexity is not necessarily required by the theory of evolution, please explain to me exactly why the development of a new pathway (requiring multiple mutations) for digesting lactose in a population of bacteria that could not previously do so is not a new trait?


I'll accept the mechanism you propose as soon as you show that it leads to the changes hypothesised. If you want to fall back on believing an untestable hypothesis, go ahead. That's your right and I won't judge you for it.

At this moment, the hypothesis we're discussing is the one that I stated earlier: descent with modification. That is, it is possible to have heritable changes which confer fitness advantages (ergo, over time, these changes will become more prevalent in a population). We can test the individual facets: that there are heritable changes and that changes can confer fitness advantages (and therefore, by extention, that these fitness advantages lead to the heritable change becoming more prevalent in a population over time).

I've shown you heritable change (the various mutations), and I've shown you heritable change that confers fitness advantage (the ability to digest nylon and the ability to digest lactose, the ability to survive better at higher temperatures).
Blight

Social climber
Oct 26, 2006 - 10:39am PT
So now, rather than simply the emergence of a novel trait, you're seeking the emergence of a novel trait which increases "complexity"?

Well, of course I am. Without increase in complexity, complex organisms can hardly have developed from simple ones.

That's what I've been getting at all along. I'm glad you're finally starting to understand.

Please describe exactly and precisely what the "pre-existing mechanism" for digesting nylon in the parent bacterium was.

I didn't say it had one. I said that it had a preexisting mechanism for adapting what it could digest.

please explain to me exactly why the development of a new pathway (requiring multiple mutations) for digesting lactose in a population of bacteria that could not previously do so is not a new trait?

They could previously do so. It's not new because it existed before. The development of complex organisms from simple ones can't happen by a process of removing then reinventing existing traits. That's not an increase in complexity.

At this moment, the hypothesis we're discussing is the one that I stated earlier: descent with modification.

And as I've now said at least four times, I don't have a problem with this part of evolution. What i have a problem with is that the changes observed and which you've reported don't seem to constitute evidence for the proposition that complex organisms can develop from simple ones. That's why i'm asking for evidence fo a new limb, organ or apparatus: that's increased complexity.
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