Evolving a new function via gene duplication and divergence

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Bjørn Østman at Pleiotropy describes new research in Science that shows how duplicated genes can evolve to perform new functions. It presents

… a new model/mechanism by which duplicated genes can retain the selection pressure to not succumb to deleterious mutations. They call it the innovation-amplification-divergene model (IAD).

Basically,

IAD works like this: A gene initially has one function only (A). Then some genetic changes makes it also have a new function, b, which at first is not of too great importance. Then some environmental change favors the gene variants with the minor b-function (the innovation stage). This is then followed by duplication of the gene, such that there are now more than one copy that carries out A and b (the amplification stage). At this stage there is selection for more b, and at some point genetic changes in one of the copies results in a gene that is better at the new function, B. At this point, selection for the genes that do both A and b is relaxed, because the new gene (blue) carries out the new function. The original gene then loses the b function, and we are left with two distinct genes.

Michael Behe, of course, scoffs. Because the researchers did some manipulations that created conditions favorable to the evolution of the new function, Behe claims that

Needless to say, this ain’t how unaided nature works – unless nature is guiding events toward a goal.

Shucks. I guess every experimental manipulation ever performed has been an invalid method of studying some process. But as a PT crew member pointed out on the back channel, “this kind of shit happens all the time in nature.” See, for example, Gene duplication and the adaptive evolution of a classic genetic switch or Escape from adaptive conflict after duplication in an anthocyanin pathway gene.

86 Comments

Well see, you have to do experiments if evolution is going to be science (never mind that they never do a sound test for “design”), but everything’s thrown off if you actually use controls and variables. Because, uh, that’s using your brain–I guess we’d have to hire brainless IDiots to do it all, and since nothing would make sense that way,…

Of course they don’t care about experiments, they’re doing religion. Religion doesn’t need experiments because it’s not in doubt (or they’d be sinning) in their minds.

Glen Davidson

You see, there is always an intelligent designer behind experiments. Therefore, all experiments prove an intelligent designer.

QED.

Cue: incoherent medieval troll appearance and subsequent Wall banishment in 3, 2 …

Funny. Just this morning on the previous thread I was saying that even if Behe’s test of evolution was demonstrated in the laboratory, Behe would dismiss the evidence because it was not natural…and then – BING! – right on cue…

Not only did the new function evolve, but it did so in just three thousand generations. A dramatic demonstration of the power of gene duplication in the evolution of novel traits. And of course, there is absolutely no reason why the same mechanism couldn’t work for more complex traits as well.

It;s almost as if the entire scientific community is conspiring to make Behe look bad. Or maybe he just always chooses the wrong side of every issue.

Not only did the new function evolve, but it did so in just three thousand generations. A dramatic demonstration of the importance of gene duplication in the evolution of novel traits. Of course, the same mechanism would work for more complex traits as well.

It’s almost as if the entire scientific community is conspiring to make Behe look bad. Or maybe he just chooses the wrong side of every issue.

DS said:

Not only did the new function evolve, but it did so in just three thousand generations. A dramatic demonstration of the importance of gene duplication in the evolution of novel traits. Of course, the same mechanism would work for more complex traits as well.

It’s almost as if the entire scientific community is conspiring to make Behe look bad. Or maybe he just chooses the wrong side of every issue.

You can say that again. Oh, you did. :)

Behe appears to have reached the point of quarreling with the fundamental methods of scientific research. I hope that the next time he turns up as an expert witness, he gets skewered with this.

Opposing counsel asks:

Dr Behe, how would you demonstrate that you actually are, rather than merely claim to be, a scientist?

This comment has been moved to The Bathroom Wall.

Moo Moo, I read the entire paper. And I learned that there is a model that explains the origin of new gene function without relaxed selection, which is important to avoid the production of pseudogenes. They also verified the model histidine/tryptophan specialization in using Salmonella. More here.

This comment has been moved to The Bathroom Wall.

parictis said:

Moo Moo, I read the entire paper. And I learned that there is a model that explains the origin of new gene function without relaxed selection, which is important to avoid the production of pseudogenes. They also verified the model histidine/tryptophan specialization in using Salmonella. More here.

In other words, the paper repeatedly proves that Behe is wrong on, many, many, many levels in addition to his laughable dismissal of the paper, and inane remark about nature being goal-oriented.

DS said:

Not only did the new function evolve, but it did so in just three thousand generations. A dramatic demonstration of the power of gene duplication in the evolution of novel traits. And of course, there is absolutely no reason why the same mechanism couldn’t work for more complex traits as well.

It;s almost as if the entire scientific community is conspiring to make Behe look bad. Or maybe he just always chooses the wrong side of every issue.

It doesn’t count unless the experiment produces a bacterial flagellum from scratch. ;-)

I’ve had the “intelligent design” of an experiment discussion with IDiots before. They really don’t have a clue how to do science.

First, if the answer was known by the experimental designer, then there wouldn’t be a lot of point in doing the experiment would there.

Second, even well designed experiments can produce unexpected data. If this wasn’t the case, then every casino game engineer would be a multi-billionaire. They designed the roulette wheel, therefore, they know what every spin will be right?

Third, experiments are designed to reduce the uncertainty and ambiguity of the experiment. Throwing a bunch of random chemicals and adding random amounts of outside influences (water, electricity, heat, etc) may produce something interesting, but how and why? A well designed experiment reduces the uncertain part to one variable that is, in turn, controlled by one independent variable. If you experiment with a pendulum, you don’t vary the length of the string, the mass of the bob, and the height you release it from and then try to figure out the difference in period and or the difference in g in the area. No, you intelligently change on aspect a time, in order to determine that aspect’s influence on one and only one other aspect (length of string and period, for example).

Experiments that are not intelligently designed are useless. However, as shown, this does not mean that all experiments are evidence of intelligent design in the rest of the universe. It is evidence that humans are intelligent and can design a valid experiment that produces useful, unambiguous, and certain results. That’s all.

If one wants to extrapolate this concept to Intelligent Design of the universe and every living thing in it, the one should first find the Intelligence that designed everything and ask that Intelligence why they did such a piss-poor job in designing the experiment that is our universe.

I like pigliucci’s analogy. Experiments are to evolving life as a telescope is to galaxies and stars.

Starbuck said:

I like pigliucci’s analogy. Experiments are to evolving life as a telescope is to galaxies and stars.

Apt analogy. This particular experiment demonstrates the importance of gene duplication in evolution, with or without selective constraints. Duplicated genes allow for neofunctionalization, even when ancestral functions are retained. Darwin would have been fascinated by these types of experiments.

You’ll never hear a creationist say, telescopes are intelligently designed, therefore those galaxies are an artifactual byproduct of the designed telescope!

ogremk5 said:

I’ve had the “intelligent design” of an experiment discussion with IDiots before. They really don’t have a clue how to do science.

First, if the answer was known by the experimental designer, then there wouldn’t be a lot of point in doing the experiment would there.

Second, even well designed experiments can produce unexpected data. If this wasn’t the case, then every casino game engineer would be a multi-billionaire. They designed the roulette wheel, therefore, they know what every spin will be right?

Third, experiments are designed to reduce the uncertainty and ambiguity of the experiment. Throwing a bunch of random chemicals and adding random amounts of outside influences (water, electricity, heat, etc) may produce something interesting, but how and why? A well designed experiment reduces the uncertain part to one variable that is, in turn, controlled by one independent variable. If you experiment with a pendulum, you don’t vary the length of the string, the mass of the bob, and the height you release it from and then try to figure out the difference in period and or the difference in g in the area. No, you intelligently change on aspect a time, in order to determine that aspect’s influence on one and only one other aspect (length of string and period, for example).

Experiments that are not intelligently designed are useless. However, as shown, this does not mean that all experiments are evidence of intelligent design in the rest of the universe. It is evidence that humans are intelligent and can design a valid experiment that produces useful, unambiguous, and certain results. That’s all.

If one wants to extrapolate this concept to Intelligent Design of the universe and every living thing in it, the one should first find the Intelligence that designed everything and ask that Intelligence why they did such a piss-poor job in designing the experiment that is our universe.

The problem with experiments is they could also prove them wrong. Need I remind you of the Wistar Incident? http://pandasthumb.org/archives/200[…]lligent.html

I’ve had the “intelligent design” of an experiment discussion with IDiots before. They really don’t have a clue how to do science.

Science is experimental and observational.

If we never did experiments, we would still be in the stone age.

That might work for creationists but the rest of us have better ways of living.

Behe denying reality some more:

Needless to say, this ain’t how unaided nature works – unless nature is guiding events toward a goal.

Nature is always guiding events toward a goal.

Natural selection, survival of the fittess, differential reproduction, however you want to term it.

Biologically, our goal is to successfully reproduce better than competing genomes.

Moo Moo -

Let’s take it one step at a time.

Can gene duplication occur? Simple yes/no question. Answer this one question.

harold said:

Moo Moo -

Let’s take it one step at a time.

Can gene duplication occur? Simple yes/no question. Answer this one question.

Who wants to go swimming in H2SO?

I was too cryptic; what I meant was a metaphor for what it would be like for people like Moo Moo to take the road you would lead them down.

Moo Moo said:

I may not understand the precise details of the science

Well, there’s your problem right there.

Yet, you don’t let that stop you from criticizing the work of people who do understand the precise details of science.

Are you actually interested in learning this stuff? What would be required (in your opinion) to show you that you are fundamentally mistaken?

In other words, do you plan to learn and understand the “precise details of science” and become an advocate for learning or do you plan to continue spewing forth your arrogant ignorance no matter what anyone else says?

Joe always makes the same mistake. He always thinks that he is more qualified to judge the experimental results than the real scientists who actually performed the research.. He is also obsesses with demanding that everyone read the entire paper, as if reading the abstract was somehow insufficient. At least he isn’t pretending to be a scientist any more. Apparently he has somehow obtained a mail order law certificate and is now calling himself a lawyer. Of course he isn’t any more a lawyer than he is a scientist.

His criticism of the research are of course completely invalid. Once again, the authors, editors and reviewers all disagree with him. But he doesn’t care. He just goes merrily on his way making ignorant claims and trying to denigrate that which he doesn’t understand. At the end of the day all he has is his own incredulity, which is of course completely worthless.

We have known about the importance of gene duplication for forty years now. Some people just can’t seem to get it through their heads. The telescope didn’t make the stars, it simply reveals them to us, just like this experiment.

Moo Moo said: This is an important feat of protein engineering but not really of undirected evolution.

Its protein engineering the same way dog breeding is protein engineering. You control the conditions to see what naturally happens under those conditions.

If you think the description of the experiment implies that scientists took teeny tiny tweezers and put together a novel gene - or something equivalent - then your reading comprehension is really poor.

From your earlier post:

At the end of the day, the “new genes” appear only to display an improved pre-existing chemical activity or even the loss of pre-existing activity that was present in the parental gene.

Just so we’re clear, then, you think that a biological system which changes from [gene A performs function 1 and 2], through [gene A duplicates to B, both A and B perform function 1 and 2] to [gene A performs function 1, gene B performs function 2] is not evolving in the sense biologists use the term evolution?

Moo Moo said:

ogremk5 said:

Moo Moo said:

I may not understand the precise details of the science

Well, there’s your problem right there.

Yet, you don’t let that stop you from criticizing the work of people who do understand the precise details of science.

Are you actually interested in learning this stuff? What would be required (in your opinion) to show you that you are fundamentally mistaken?

In other words, do you plan to learn and understand the “precise details of science” and become an advocate for learning or do you plan to continue spewing forth your arrogant ignorance no matter what anyone else says?

I am qualified to know when someone is trying to put a spin on something. In this case, the experiment was directed by the scientists who selected and reconfigured mutants in order to achieve a modification in two of the pre-existing activities of the original gene. This is an important feat of protein engineering but not really of undirected evolution.

If you don’t understand science, then how can you possibly judge whether there is “spin” or anything else?

Do you even understand the purpose of the paper in question? Do you even understand what evolution is? I haven’t seen you explain it in your own words yet, so there’s no way to judge that you even have the basics needed to begin to understand this.

Would appreciate me coming into your office (presuming you are actually a lawyer) and explaining to you have every case you are working is fundamentally flawed? Of course you wouldn’t. You’d kick me out of your office in a heartbeat.

But you think that doesn’t apply to you.

And you didn’t answer my questions.

Are you actually interested in learning this stuff? What would be required (in your opinion) to show you that you are fundamentally mistaken?

In other words, do you plan to learn and understand the “precise details of science” and become an advocate for learning or do you plan to continue spewing forth your arrogant ignorance no matter what anyone else says?

Moo Moo said:

I may not understand the precise details of the science but, having read the paper, the following things are quite revealing:

To experimentally test the IAD model, we examined a histidine biosynthetic enzyme (HisA),and through continuous selection we created, by duplication and divergence, a new gene that catalyzes a step in tryptophan synthesis.

It seems a bit odd that an experiment that purportedly demonstrates evolution involves the researchers creating a new gene, albeit through mutational means.

You are using word games to skirt around the fact that Nasvall et. al. created a new gene using the known evolutionary mechanism of gene duplication. If evolution of genes via gene duplication didn’t work the experiment would have failed.

In a strain lacking trpF, we selected a spontaneous hisA mutant of Salmonella enterica that maintained its original function (HisA).……We placed this bifunctional parental gene (dup13-15, D10G) under the control of a constitutive promoter that cotranscribed a yellow fluorescent protein ( yfp) gene.

It seems that the researchers directed and guided their experiment towards a goal by selecting various mutants and reconfiguring them to some extent.

Yeah it does seem that way doesn’t it. That is because that’s what experiments do. The part you missed is that they used aspects evolutionary theory to design their experiment. Selection is selection whether artificial or natural. Natural selection and artificial selection aren’t random and the mutations that happened to the duplicated gene in this experiment were just as random as the mutations that occur in nature. This experiment just verifies how scientists think natural selection and mutation operate on duplicated genes. i.e that one gene that performs two functions suboptimally can become two genes that perform only one function each, optimally.

The evolved genes fell into three classes: (i) specialized genes with strongly improved HisA activity and loss of TrpF activity, (ii) specialized genes with strongly improved TrpF activity and loss of HisA activity, and (iii) generalist genes whose encoded enzyme showed a moderate increase in both activities

At the end of the day, the “new genes” appear only to display an improved pre-existing chemical activity or even the loss of pre-existing activity that was present in the parental gene.

You seem to think that these results aren’t what we expected. They were exactly what was expected. What we don’t expect is entire functioning organisms or even genes for that matter created from dirt or clay. That is never observed, ever.

ogremk5 said:

And you didn’t answer my questions.

Are you actually interested in learning this stuff? What would be required (in your opinion) to show you that you are fundamentally mistaken?

In other words, do you plan to learn and understand the “precise details of science” and become an advocate for learning or do you plan to continue spewing forth your arrogant ignorance no matter what anyone else says?

Joe doesn’t answer questions. I asked him twenty seven different questions before I realized who I was dealing with, He didn’t answer any of them. Now in a court of law you could make him answer questions, but otherwise he’ll just go on ignoring them and expecting everyone to answer his stupid questions anyway. He knows that if he tries to answer he will be revealed as the ignorant science hating bigot that he is.

Seriously, is there anyone who doesn’t think that this guy is really bozo Joe? He just doesn’t have the balls to admit it.

Moo Moo said:

eric said: Its protein engineering the same way dog breeding is protein engineering. You control the conditions to see what naturally happens under those conditions.

Correct me if I am wrong, but isn’t dog breeding a form of artificial selection rather than natural selection?

Yup, but as Darwin noted, artificial selection provides insight into what nature can do without humans.

I did read the paper and they do appear to have screened the natural mutants, and to have done other things with them as well.

Do you understand that that is like deciding which dogs go in the pen, and not like taking teeny tiny tweezers and directly engineering a gene?

Just so we’re clear, then, you think that a biological system which changes from [gene A performs function 1 and 2], through [gene A duplicates to B, both A and B perform function 1 and 2] to [gene A performs function 1, gene B performs function 2] is not evolving in the sense biologists use the term evolution?

As I understand it, the original gene had two activities and the experiment produced duplicates with modified levels of activity. What you describe appears to be a division of labor rather than any innovation which is the central theme of the paper.

It appears you agree that such an evolution in gene function is allowed by nature, you just don’t want to say that outright.

Moo Moo said: I am qualified to know when someone is trying to put a spin on something. In this case, the experiment was directed by the scientists who selected and reconfigured mutants in order to achieve a modification in two of the pre-existing activities of the original gene. This is an important feat of protein engineering but not really of undirected evolution.

Not really. You’re making one of the same mistakes Phillip Johnson makes. You are assuming that common words and constructs mean in someone elses specialty mean the same as they do in your specialty.

As is frequently mentioned on Groklaw, where the bloggers *do* know the law, it is pointed out that the law uses common words in ways that don’t match up with common usage. Likewise, scientific papers have a style of discourse that doesn’t match common usage.

You are assuming that, because you are familiar with legal usage, that you are also familiar with scientific usage. It simply isn’t true.

We should perhaps talk of ‘artificial natural selection’ or some such thing when we simply create the conditions that select for certain traits that we want (when it’s not just experimenting with “natural selection,” that is).

So that if I’m trying to create an antibiotic-resistant strain of bacteria simply by growing those bacteria in increasing quantities of that antibiotic–and not selecting the reproducers by artifice–that would be artificial natural selection.

Glen Davidson

or just “selection”

It’s really not complicated. “Artificial selection”, which is to all extents and purposes a needlessly fancy term for “breeding”, is a type of natural selection.

Can it be distinguished from other types of natural selection? Yes, it usually can. And walnuts can usually be distinguished from other types of tree nuts, but they’re still tree nuts.

Creationists try to discount many otherwise undeniable examples of evolution through genetic diversity and selection, by pretending that “artificial selection” is in some way unnatural or magical.

Creationists themselves can’t be changed but their slogans do confuse well-meaning third parties. For the benefit of third parties, it helps to clarify things.

Human breeding of domestic animals and plants is a uniqute type of evolution, but it’s still evolution, and the selection involved is still natural.

Paul Burnett said: Challenge sentence for translation programs: “Fruit flies like bananas; time flies like an arrow.”

My wife (her degree is in Linguistics) cites that line as a matter of supersegmentals.

The “classic” computer translation anecdotes are:

English–> Russian–> English, “The spirit is willing but the flesh is weak” becomes “the vodka is good but the meat is rotten.”

English–> Chinese–> Englsih, A treatise on a “hydraulic ram” comes back out talking about a “water goat”.

W. H. Heydt said: English–> Russian–> English, “The spirit is willing but the flesh is weak” becomes “the vodka is good but the meat is rotten.”

That example seems to have been around at least 50 years, according to an article cited in Wikipedia “Literal translation”, and Snopes suspects that it is apocryphal.

W. H. Heydt said: English–> Chinese–> English, A treatise on a “hydraulic ram” comes back out talking about a “water goat”.

“Out of sight, out of mind becomes “Invisible and insane.”

“Out of sight, out of mind” becomes “Invisible and insane.”

PT needs a post-submission editing function…

harold said:

It’s really not complicated. “Artificial selection”, which is to all extents and purposes a needlessly fancy term for “breeding”, is a type of natural selection.

Well, most wouldn’t really go that far. There’s a real difference between, say, a mouse bred up to be very vulnerable to cancer, and one that has been “selected” by the environment to be reproductively fit. Certainly it’s all “natural,” and there’s no actual break between natural selection and artificial selection, but the terms as used are quite meaningful in a practical sense.

“Artificial selection” tends to be used because “breeding” is not a very precise term, as we have “breeding” in the wild and then “breeding” of more useful varieties. And, of course, it suggests the analogy with “natural selection” to speak or write of “artificial selection.”

Can it be distinguished from other types of natural selection? Yes, it usually can. And walnuts can usually be distinguished from other types of tree nuts, but they’re still tree nuts.

But in many cases it is quite important to distinguish between “artificial selection” and “natural selection.” The domestic cow produces milk at quantities that serve our purposes. The wild cow produces milk at quantities at times to balance out her continued survival and reproduction, with the success of her calf. Evolutionarily, artificial selection is actually an example of design, and may be detected against the background of natural selection according to usual aspects of design, such as rationality’s apparent involvement, as well as the purpose behind it.

To be sure, genetic engineering is all the more obvious as design, as opposed to what happens “naturally.”

Creationists try to discount many otherwise undeniable examples of evolution through genetic diversity and selection, by pretending that “artificial selection” is in some way unnatural or magical.

Yet the actual features that differ domestic organisms from “wild-type” organisms should not be discounted. Of course artificial selection isn’t magical, as they often assume (the mind being magical for nearly all creationists), nevertheless it produces organisms that do incorporate some designed aspects, which are obvious against the background of wholly undesigned organisms.

Creationists themselves can’t be changed but their slogans do confuse well-meaning third parties. For the benefit of third parties, it helps to clarify things.

That’s why we can’t deprecate the importance of artifice involved in genetic engineering and in artificial selection. Artificially selected organisms differ from wild-type organisms in important ways, with the lack of any identifiable purpose and rational design being important markers for wild-type organisms.

Human breeding of domestic animals and plants is a uniqute type of evolution, but it’s still evolution, and the selection involved is still natural.

In the context of the supernatural-natural distinction, of course it’s “natural.” But what known phenomenon isn’t in that sense? In the common sense of what occurs “naturally” and what is “done by artifice,” it remains important that bizarre strains of mice are in fact artificially selected. We do not explain hairless cats according to “normal” natural selection at all, we have to resort to human desires to explain those.

The very lack of obvious artifice in “natural selection”–and also in all known wild-type organisms–remains a crucial difference between “natural selection” and “artificial selection.”

Glen Davidson

“Artificial” selection and “natural” selection differ not in the populations under selective pressure in one or the other, but only in the source of the selective environment. What happens in the populations under selective pressure–differential reproductive success as a function of the adaptiveness of varying traits in a given selective environment–does not differ. Mutations that are random with respect to the selective environment, whether or not that environment includes human “desires”, are successful or not in that selective environment depending on their effect on the relative reproductive rate of variants with and without the mutations. Gene frequencies change, due both to the selective environment and drift, and populations shift on the fitness landscape. That humans are tinkering with the shape of the fitness landscape doesn’t alter the core process.

Question for the pros in biology, ethology, philosophy or anything pertinent:

Let us stipulate that artificial selection is the INTENTIONAL selection of organisms with desired traits in order to proliferate or enhance those traits in offspring. I suspect that humans were enhancing the transmission of useful traits before they realized they were doing that, or that they could do it on purpose.

But that aside, here’s the question: Are there any other species that might be said to practice artificial selection of other organisms in their environment, i.e., selecting organisms for survival and reproduction in such a way that the selected-upon organisms are gradually improved from the point of view of the selecting species? (A fox selecting for faster rabbits wouldn’t count, because faster rabbits are not better from the fox’s point of view.)

I realize that many would balk at assigning intention or purpose to non-human animals, but let’s be generous for the sake of argument. If humans many thousands of years ago were practicing artificial selection when they decided to keep around the most tractable of the wolf pups (and probably ate the others), without really realizing that over generations they were selecting for and fixing genes for tameness, then might some other species be doing something similar?

Some ant species ‘farm’ fungi. It’s not clear to what degree (if any) traits of the fungi are due to selection practiced by the ants, though I wouldn’t be amazed if it were the case. The fungi apparently have some traits, The ants apparently use chemical agents, like chemicals that fight microfungal ‘weeds,’ that might be candidates for the practice of (unconscious) selection by the ants. See here for an example.

(Edited to make it clear that the fungi don’t produce the agents, but rather apparently the ants use anti-weed bacterial agents.)

I was thinking of social insects as possible candidates. Might not bees be selecting for flowers that are more beneficial to the bees by selectively pollinating those that offer the most nectar or are otherwise more attractive?

Come to think of it, don’t many animals select for improved fruit by selectively eating the “best” fruit, and thereby distributing the seeds?

Richard B. Hoppe said:

“Artificial” selection and “natural” selection differ not in the populations under selective pressure in one or the other, but only in the source of the selective environment. What happens in the populations under selective pressure–differential reproductive success as a function of the adaptiveness of varying traits in a given selective environment–does not differ. Mutations that are random with respect to the selective environment, whether or not that environment includes human “desires”, are successful or not in that selective environment depending on their effect on the relative reproductive rate of variants with and without the mutations. Gene frequencies change, due both to the selective environment and drift, and populations shift on the fitness landscape. That humans are tinkering with the shape of the fitness landscape doesn’t alter the core process.

I couldn’t have said it better myself.

In fact I didn’t. Thank you.

Just Bob said:

I was thinking of social insects as possible candidates. Might not bees be selecting for flowers that are more beneficial to the bees by selectively pollinating those that offer the most nectar or are otherwise more attractive?

Come to think of it, don’t many animals select for improved fruit by selectively eating the “best” fruit, and thereby distributing the seeds?

The last time this came up, someone, I think Gary Hurd, did suggest that domestication could perhaps be considered a form of symbiosis or commensalism.

Paul Burnett said:

Mike Elzinga said: Hah; time flies.

Challenge sentence for translation programs: “Fruit flies like bananas; time flies like an arrow.”

Time flies infest the TARDIS.

I guess my point is the same as others have been getting at: “artificial” and “natural” selection are a distinction without a real difference. If humans unintentionally modifying wolves, wild cattle, sheep, etc. into early domesticated breeds is “artificial” selection, then so must the unintentional modification of flowers, fruits, and probably many more things by other animals be “artificial” selection. The modification in both cases benefits the modifier, but is done entirely without a goal in mind of ‘improving the breed’.

As others have said: it’s all natural.

Yet the actual features that differ domestic organisms from “wild-type” organisms should not be discounted. Of course artificial selection isn’t magical, as they often assume (the mind being magical for nearly all creationists), nevertheless it produces organisms that do incorporate some designed aspects, which are obvious against the background of wholly undesigned organisms.

Yep, and that’s a pattern that wouldn’t be there if life were in fact designed outside of the occasional human influence on it.

I suppose one difference between artificial and natural selection is that breeders try to reduce the variables to just the ones they think are important, while in nature the variables are apt to be, um, much more variable.

What if instead of “artificial” the word “deliberate” were used instead?

I suspect that the word “selection” keeps getting used because “differential reproductive success of genetic variations” is somewhat of a mouthful.

Come to think of it, don’t many animals select for improved fruit by selectively eating the “best” fruit, and thereby distributing the seeds?

That could well be what caused fruit to evolve in the first place. (Which is good, because otherwise living in this world would be fruitless.)

Paul Burnett said:

Mike Elzinga said: Hah; time flies.

Challenge sentence for translation programs: “Fruit flies like bananas; time flies like an arrow.”

Well of course fruit flies like bananas. Because from the flies POV, a banana has a peel.

The term “natural selection” was invented by Darwin because he and everyone else knew about selective breeding, and his argument was that selective breeding also takes place in natural environments. Hence, natural selection. His entire point was that natural selection and selective breeding were the same process.

Yet the actual features that differ domestic organisms from “wild-type” organisms should not be discounted. Of course artificial selection isn’t magical, as they often assume (the mind being magical for nearly all creationists), nevertheless it produces organisms that do incorporate some designed aspects, which are obvious against the background of wholly undesigned organisms.

Yes, that’s another thing creationists do. That’s pure vintage 1995-Dover “the designer might be an alien” ID. The false analogy between design by known designers and magical design by unknown, unnameable designers.

Maybe they stole that from Paley or maybe they came up with the same bad idea on their own.

There were, in the end, exactly two “original”, or more strictly, repackaged, contributions by ID - “it looks complicated so it couldn’t have evolved and must have been designed”, which is all that “irreducible complexity”, “CSI”, etc, actually are, and which is argument from incredulity and false dichotomy, and “humans designed something therefore a deity or alien must have designed the bacterial flagellum”, which is an invalid analogy and a non sequitur.

That’s really all there ever was to ID, even though millions or billions or words of verbose BS were expended.

However, of course, the population of people who care about 1995-to-Dover era ID is now in the flatter phase of exponential decay. It dropped off sharply after it was proven useless for its goal of “court-proofing” sectarian evolution denial in public schools. Today Dembski himself is teaching at an obscure fundamentalist YEC seminary. There are still a tiny number of “ID isn’t religious” types around the internet, but they are probably about 1% of what they were in 2004, and they won’t be replaced when they die off.

The point of ID was to grit your teach and pretend that you weren’t a creationist, so that you could use illogical sophistry to deny evolution to schoolchildren on the taxpayer’s dime, with the goal of semi-secretly implying creationism. Once the “deny evolution to schoolchildren on the taxpayer’s dime” part failed, the exercise became somewhat pointless.

The bait and switch between “artificial” and “miraculous” because each is “the opposite of natural” is a different, older game, frequ

whoops…

The bait and switch between “artificial” and “miraculous” because each is “the opposite of natural” is a different, older game, frequently played by overt YEC types, as here.

Henry J said:

What if instead of “artificial” the word “deliberate” were used instead?

Chris Lawson said:

…natural selection and selective breeding [are] the same process.

Natural selection vs. controlled selection?

Chris Lawson said: … His entire point was that natural selection and selective breeding were the same process.

Compare teosinte and corn.

The difference is noticeable.

Glen Davidson

harold said:

The point of ID was to grit your teach…

Freudian Slip of the Month!

https://me.yahoo.com/a/JxVN0eQFqtmg[…]X_Zhn8#57cad said:

Chris Lawson said: … His entire point was that natural selection and selective breeding were the same process.

Compare teosinte and corn.

The difference is noticeable.

Glen Davidson

Alright, I will compare teosinte to domestic maize strains.

Domestic maize strains are the result of a primate species naturally selecting, in a particular environment, strains of a wild grain, probably teosinte.

The primates probably noticed that some teosinte plants had more or larger seeds, and also noticed that the offspring of those plants also tended to have more and larger seeds. In other words, thousands of years ago, they figured out some key principles of evolution - genetic variation and selection.

There is not a single comment in this thread that says that examples of human breeding cannot be distinguished from other examples of natural selection. It’s rather shocking that you keep implying that someone has said that, and that is what you seem to imply, unless I am misinterpreting.

It is perfectly true that modern teosinte has been acted on by different selective pressures than have modern strains of domestic maize over the years since they diverged.

It’s also perfectly true that sea urchins have been acted on by different selective pressures than oak trees, since their common ancestors diverged.

No-one is saying that all natural selection is homogeneous, or that different types of natural selection cannot be distinguished from one another, or that human agricultural breeding isn’t different in many ways from other types of natural selection.

Glen Davidson -

I should add, I really don’t think we have a dispute here.

I completely agree that the results of human breeding, whether domestic maize or delicate transgenic mice that can only survive in a special human-created environment, tend to be different from the results of other selective forces.

However, I’m sure we both agree that…

1) The process of human deliberate breeding is, among other things, A) natural and B) selection.

2) The fact that humans can “design”, and that we can recognize the “designs” of other humans, including but not limited to products of breeding, does not imply that the bacterial flagellum, Adam and Eve, the first replicating cell on earth, or anything else, had to be “designed” by a deity.

I’m sure you agree with these points, so beyond that, stylistic disputes about the use of the term “artificial selection” have reached an impasse.

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This page contains a single entry by Richard B. Hoppe published on November 12, 2012 5:06 PM.

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