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TradIsGood

Fun-loving climber
the Gunks end of the country
Oct 24, 2006 - 09:30am PT
A good start...

Definitely not enough. :-)

I descended from my parents, modified, but not a new species.
Aya

Uncategorizable climber
New York
Oct 24, 2006 - 09:44am PT
Well now you're asking about speciation, for which evolution is simply one potential mechanism - not evolution itself!
Blight

Social climber
Oct 24, 2006 - 09:46am PT
You write that "To sum this up succinctly: the theory of evolution states that simple unicellular organisms evolved into multicellular ones with complex organs, limbs and apparatuses," but the point is that this is false

Well...wow.

I'm intrigued - in fact my head is buzzing with the possibilities of what you might believe!

Do you disagree that life began with simple organisms? (perhaps you think that abiogenesis yielded complex multicellular organisms in one step? Surely not.)

Perhaps you disagree that simple organisms developed by process of modification into more complex ones? (Goodness knows, Raymond could hardly be simpler! ;)

Or perhaps you disagree that organisms now have complex limbs, organs and apparatuses? (er....okay)

Please be specific: which part of my statement do you disagree with and why?
raymond phule

climber
Oct 24, 2006 - 09:48am PT
"Raymond edit:
I think the statement asking for a demonstration is evidence that he admits that he could be wrong. I do not see evidence for the assertion of fundamentalism. Maybe you could offer a scientific statement, instead of a character assessment. :-)"

I have "discussed" with Blight on this and another thread. I came to the above conclusion and stand for it.

If a person cant admitt that the section "The Design" in the following article is con evolution and pro inteligent design.
http://www.doesgodexist.org/Phamplets/Mansproof.html

Then is it very easy to came to my above conclusion.
eeyonkee

Trad climber
Golden, CO
Oct 24, 2006 - 09:58am PT
Descent with Modification.

Darwin's own words. In fact, he never even mentions the word evolution until the last paragraph of the Origin Of Species.

Aya, perhaps you are not familiar with "The Selfish Gene". What Dawkins proposes is more or less the other side of the coin from Group Selection (which he pretty much poo-poohs). It's kind of a difficult concept to get your head around, and I probably can't do justice to it in a paragraph or two.
Aya

Uncategorizable climber
New York
Oct 24, 2006 - 10:00am PT
Blight -

I agree that life began with simple organisms. I agree that complex organisms developed from less complex ones. I agree that organisms have complex limbs and structures.

I disagree that these points are what the theory of evolution states. It states no such thing. I wasn't being facetious when I used three words to describe evolution.

Descent with modification.

That is a mechanism by which complex, multicellular organisms with limbs might appear. It does not say that they WILL evolve. It just explains how they can. Which, again, is why it is important for you to express exactly what you understand evolution to be.
Blight

Social climber
Oct 24, 2006 - 10:04am PT
Hmmm.

Perhaps I've been misuing some terminology.

Could you please tell me:

What does evolution state?

And what name is given to the process we have agreed is supposed to have occurred?
Jaybro

Social climber
The West
Oct 24, 2006 - 10:11am PT
"I descended from my parents, modified, but not a new species."

Would your mom agree? ha-ha

I'm a custom job myself.

If any ony can scan or link to todays' Bizarro comic it is surprisingly relevent.
Ed Hartouni

Trad climber
Livermore, CA
Oct 24, 2006 - 11:18am PT
Blight, the evidence that you seek, the "evolution" of an organism right before your eyes, cannot be done. That is not what the theory of evolution is about and so from a scientific viewpoint it is irrelevant to the discussion regarding the validity of the theory.

In fact this is true of all theories of science. You could just as well ask "show me a wave function or I won't believe quantum mechanics" or "show me an atom," or "make a 'big bang' in the lab," you could require any number of evidences that fit your own way of sensing...

...you could state that instrumental enhancements of our ability to sense only falsify what is being sensed, thus no conclusion inferred from these instruments are real. That is exactly what happened to Gallileo, the church ruled that looking through a telescope alters the light rays, and thus the result, a magnified image, did not contain "truth".

If you eliminate all inference and demand direct experience as your only accepted manner of learning about the world then you must reject almost all of science itself. Science reveals a world very much beyond what we would initially think was 'common sense.' The methods used to reveal this are objective and reproducable and predictive. You can, of course, reject this entirely and demand any 'proof' you wish and then claim, erroneously, that the theory cannot be true as it cannot satisfy your own test. Your test is irrelevant to the veracity of the theory.

You are barking up the wrong tree; I will defend your right to bark, but you make yourself out to be the fool on this one.
graniteclimber

Trad climber
Nowhere
Oct 24, 2006 - 11:22am PT
"I've spent the last 10 years looking for evidence. I have consulted scientists, researchers, professors, journals and papers by the thousand. I have found none."

Then you are looking in the wrong places or not able to comprehend the material.


"If you don't want to help out, fine, I won't ask you to. Quit posting. I'm not going to use your refusal to help as evidence that I'm right.

If you do want to post again, please stay on topic instead of quoting irrelevant posts from unconnected threads..."

That's not how the Internet works. :-) When I defended Blight above, I naively believed he was genuinely interested in an honest intellectual discussion. However, after stumbling across Blight's numerous posts on this subject in the past, it became clear to me that he is not interested in an honest discussion at all but rather is pushing a extremist fundamentalist position. He engages in arguments that are in my opinion intellectually dishonest and put-downs when convenient.



As I've stated above in a post that Blight did not respond to, the whole cornerstone of his Blight's position is that no new genetic material appears. Blight correctly asserts that new genetic material (i.e. mutations) are essential for evolution to occur.

However this is easily proven wrong, as mutations are routinely observed in laboratories. The predictable response from Blight (this has all been discussed ad nauseum in past threads) is along the lines that he doesn't want to see trivial changes in fruit flies, but something on the order of a cat or dog growing a new organ.

That might be what Blight wants to see, but it's not necessary for disproving his assertion that no new genetic material appears as being factually inaccurate. New material is new material. All that is needed to disprove is observing one mutation, and this has been done, more then once.

Also, anyone with a basic understanding of the theory of evolution knows that the appearance of an entirely new organ is not something that you would expect to appear in a laboratory. That is like requesting the Grand Canyon to be replicated in full scale in a laboratory--its a ridiculous request. And I expect that Blight knows this.

Before spending very much time putting together detailed, thoughtful responses to Blight's demands, look at the previous postings on evolution here on Supertopo and form your own conclusion as to whether Blight is genuinely interested in learning more about evolution or if he is only seeking to confound.
TradIsGood

Fun-loving climber
the Gunks end of the country
Oct 24, 2006 - 11:41am PT
Well we were making a little progress for a moment, in deciding what the theory says, but now we have people jumping ahead and discussing it relative to what it means to them and making assertions.

Ed asserts that the theory does not say that changes of an organism are observable (which may be true), but do we have to add to "descent with modification" to get that?

Are we agreed on "descent with modification" as a full statement, or does it need more?

And granite is into genetics and post darwin developments. Are they a part of this theory? Is DNA a part of evolution, or is it complementary?

Without rigor, how can we evaluate the veracity of a statement? Do we say that an electron is a wave function? Or do we say that modelling it mathematically as a wave function, or superpositions of wave functions, that are solutions to a partial differential equation, explains more fully its dual wave-particle nature?

Blight

Social climber
Oct 24, 2006 - 11:56am PT
There seem to be conflicting opinions:

Ed insists that the evidence I seek is non-observable.

However, graniteclimber insists that the evidence is not only observable, it has already been observed.

They do however share a common flaw: the evidence I'm asking for is neither of an impossibly large or an impossibly small scale, nor is it abstract. I'm not asking you to use a blue whale or an atom, something simple like a fruit fly will do.

All that is needed to disprove is observing one mutation, and this has been done, more then once.

1. Mutations are not new genetic material. They are replications of existing material. As an example, you can create a fly with 3 eyes. But that's not a new organ; flies already have eyes.

2. Changes need to be sustainable. In all cases to date, mutations either lead to sterility or they simply disappear.]

3. Changes must be net positive, and possible without interference.

I've never seen or read of a case which fitted all 3 of these criteria, which are critical to the development of species as presently understood.
TradIsGood

Fun-loving climber
the Gunks end of the country
Oct 24, 2006 - 12:04pm PT
Whoa - now Blight is jumping ahead to conclusions, without a formal statement of the theory.

The conclusions that 1, 2, and 3 follow from the theory is not clear, since you have yet to state the theory.

Sorry, try again.



160-137 = 23 and counting. My new prediction is that by post 274, there will still be no agreement on what the theory is, but there will still be an argument about whether people are right or wrong!

Prove me wrong, please!
graniteclimber

Trad climber
Nowhere
Oct 24, 2006 - 12:05pm PT
"Descent with modification."

Good post, Aya. So much attention is paid to the "monkeys to man" scenario that the basic process is often overlooked and poorly understood.

Genetic mutations produce variation in a population's phenotypes (in other words, physical differences between individuals of the population.

Some of these differences confer an advantage on the individuals which possess these differences. This advantage allows these individuals, on average, to survive and reproduce at a higher rate then the rest of the population.

Because the advantageous mutations are genetic, they are passed down to offspring. Because the individuals holding the mutation are reproducing at a higher rate, on average, we can expect the percentage of the population having the mutation to increase over time - this is often referred to as "survival of the fittest."

I'm sure others can articulate if far better then me, but that is the process of evolution in a nutshell.

Most people intuitively "get" the survival of the fittest part. Where they stumble is in understanding the process of mutations.

From what has been observed, most mutations either do not effect an organism's phenotype at all or they have a negative effect. But the "bad" mutations are self-limiting because they limit the their hosting organism's ability to survive and reproduce. The changes that spread through populations over time all arise from the "good mutations."

The ongoing process of evolution is distinguishable from the theories regarding the origin of animals and peoples (although they are closely related.) The process of evolution is provable in laboratories. Although there is a great deal of compelling evidence regarding the role of the process of evolution in the origins of animals and people, these are past events, this is not provable by laboratory experiment or direct observation (unless you invent a time machine.)

Fundamentalists (such as Blight) often sieze on this to ridicule the application of the process of evolution to our orgins. The conveniently overlook the fact that no historical events are observable by us, and this includes all Biblical events.

TradIsGood

Fun-loving climber
the Gunks end of the country
Oct 24, 2006 - 12:22pm PT
Nice Granite...

Genetic mutations produce variation in a population's phenotypes (in other words, physical differences between individuals of the population.

Some of these differences confer an advantage on the individuals which possess these differences. This advantage allows these individuals, on average, to survive and reproduce at a higher rate then the rest of the population.

Because the advantageous mutations are genetic, they are passed down to offspring. Because the individuals holding the mutation are reproducing at a higher rate, on average, we can expect the percentage of the population having the mutation to increase over time - this is often referred to as "survival of the fittest."




Is this enough?

Can we agree on at least this?

It definitely does not say the speciation does or does not occur. It could say only that a species will change physically and that the percentage of a population of a species will change?

Do we need to add geography to this?
Ed Hartouni

Trad climber
Livermore, CA
Oct 24, 2006 - 12:23pm PT
"Ed asserts that the theory does not say that changes of an organism are observable (which may be true), but do we have to add to "descent with modification" to get that? "

I didn't say that, I said that you couldn't do it in a lab while you are watching (at least not in a way you would accept, bacteria can be observed to evolve, but you would say "not good enough, I want to see wings!")

The observables are all around you, they are the stuff of all biology... the fossil record... geology.... yet you assert that this is only "inferential" and therefore not acceptable as evidence. Blight is from Missouri, the "show me" state, he wants to see it happen "with his own eyes" yet his eyes are closed to the evidence around him.

He willfully blinds himself to the evidence so that he can maintain a smug viewpoint, that evolution is absurd... well sometimes nature is absurd, but as scientists, we take it as it is...

Blight, do you have anything more to add to this discussion, you will not change your viewpoint, and you cannot change my viewpoint.
graniteclimber

Trad climber
Nowhere
Oct 24, 2006 - 12:23pm PT
"Mutations are not new genetic material. They are replications of existing material. As an example, you can create a fly with 3 eyes. But that's not a new organ; flies already have eyes"

This statement has so many false statements in it, I don't even know where to start. And, just as I predicted, Blight is repeating his call for observation of a completely new organ, which is absolutely ridiculous. What Blight is asking for, the spontantous development of a completely new organ overnight, is soemthing that would not be expected to follow form the process of evolution.

It's not surprising the ten years of research has gotten Blight nowhere.

Any change in the genetic code is a mutation by definition.

Edit: Type "mutation" into Google and hit the "I'm Feeling Lucky" button. Then read the first sentence.
TradIsGood

Fun-loving climber
the Gunks end of the country
Oct 24, 2006 - 12:46pm PT
Some of these differences confer an advantage on the individuals which possess these differences. This advantage allows these individuals, on average, to survive and reproduce at a higher rate then the rest of the population.

Because the advantageous mutations are genetic, they are passed down to offspring. Because the individuals holding the mutation are reproducing at a higher rate, on average, we can expect the percentage of the population having the mutation to increase over time - this is often referred to as "survival of the fittest."


Suppose:
 variants Va and Vb of a virus reproduce such that the reproductive rate R follows Ra >> Rb.
 each variant can reproduce only in one host species.
 Va causes its host to die, in general, too rapidly for it to be spread widely to other instance of the host species.
 So it has a "local" reproductive advantage, but a "global" disadvantage.
 Or Ra is low enough that it infects an entire regional population of its host which has insufficient mobility, so that the reproductive advantage is "regional", but is limited by the mobility of the host.

 The net effect in either case being that the temporarily advantaged Va drives out Vb, followed by its own extinction, despite the fact that Vb might have been sufficiently communicable to infect and live indefinitely in a population.

 Or a single instance of the host regionally infected by Vb, escapes the region, prior to the local extermination of the host and infection of Va.
eeyonkee

Trad climber
Golden, CO
Oct 24, 2006 - 01:14pm PT
There's a good treatment of how the eye might have evolved (and apparently, it has evolved separately more than once) in Dawkins, "The Blind Watchmaker". I would suggest that Blight read it. Actually, I would suggest that anybody who's interested in this stuff readit.
graniteclimber

Trad climber
Nowhere
Oct 24, 2006 - 01:22pm PT
Tradisgood,

"Is DNA a part of evolution, or is it complementary?

DNA was not part of Darwin's theory at all, as it hadn't been discovered yet. But it is intrinsic to the Modern Synthesis as it is explains exactly how the process occurs. Darwin could identify what was happening but he (and others of his time) lacked the knowledge to explain how it happened. There were some notions as to how heredity occurred based on animal breeding, but heredity was poorly understood. Mendel presented his first paper on heredity a few years later, but its implications weren't understood until later.

Mendelian genetics was enough to have a good understanding of evolution, kind of like how you can have a theory of gravity without knowing about gravitational waves. But know that we can sequence DNA, we can observe mutations firsthand. It's like being able to look directly into a box as opposed to looking at a closed box and postulating about what is happening inside based on the input and output.

"Do we need to add geography to this?"

You ARE sharp. I was trying to keep it simple and just focus on the basic process!

You can see geography as being incorporated within the notion of "population" or rather "breeding population." The constraints on breeding populations are usually geographical, but will vary depending on the species. For example, contrast the Arctic Tern (which flies from polar region to polar region and has such a wide range that there is effectively only one breeding population) to tortoises which are distributed into many, many breeding populations throughout the world.

Having more then one breeding population is considered the key factor in a species forking into subspecies and then ultimately into different species. But even in a single breeding population, the process of evolution is ongoing. In other words, species differentiation is a consequence of the process of evolution proceeding in two (or more) different breeding populations, but is not required to explain the basic process.
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