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New evidence that natural selection is a general driving force behind the origin of species
Vanderbilt University ^ | 23 February 2006 | Staff

Posted on 02/24/2006 4:12:32 AM PST by PatrickHenry

Charles Darwin would undoubtedly be both pleased and chagrined.

The famous scientist would be pleased because a study published online this week provides the first clear evidence that natural selection, his favored mechanism of evolution, drives the process of species formation in a wide variety of plants and animals. But he would be chagrined because it has taken nearly 150 years to do so.

What Darwin did in his revolutionary treatise, “On the Origin of Species,” was to explain how much of the extraordinary variety of biological traits possessed by plants and animals arises from a single process, natural selection. Since then a large number of studies and observations have supported and extended his original work. However, linking natural selection to the origin of the 30 to 100 million different species estimated to inhabit the earth, has proven considerably more elusive.

In the last 20 years, studies of a number of specific species have demonstrated that natural selection can cause sub-populations to adapt to new environments in ways that reduce their ability to interbreed, an essential first step in the formation of a new species. However, biologists have not known whether these cases represent special exceptions or illustrate a general rule.

The new study – published online in the Proceedings of the National Academy of Sciences – provides empirical support for the proposition that natural selection is a general force behind the formation of new species by analyzing the relationship between natural selection and the ability to interbreed in hundreds of different organisms – ranging from plants through insects, fish, frogs and birds – and finding that the overall link between them is positive.

“This helps fill a big gap that has existed in evolutionary studies,” says Daniel Funk, assistant professor of biological sciences at Vanderbilt University. He authored the study with Patrik Nosil from Simon Fraser University in British Columbia and William J. Etges from the University of Arkansas. “We have known for some time that when species invade a new environment or ecological niche, a common result is the formation of a great diversity of new species. However, we haven’t really understood how or whether the process of adaptation generally drives this pattern of species diversification.”

The specific question that Funk and his colleagues set out to answer is whether there is a positive link between the degree of adaptation to different environments by closely related groups and the extent to which they can interbreed, what biologists call reproductive isolation.

Funk and his colleagues saw a way to address this question by extending a method pioneered by two scientists in a now classic study of species formation in fruit flies published in 1989. The original method measured the way in which reproductive isolation varies with time. It proved to be very powerful and a number of other researchers applied it to additional species. Funk and his colleagues realized that if they used the results of these studies and added an ecological dimension then they would have an approach capable of measuring the link between natural selection and reproductive isolation.

“We thought that the idea itself was important, that this is a really powerful approach to a very major question,” says Funk, “but we thought that there was no way in the world that we were actually going to get statistically significant results.”

The reason for his doubt was the incompleteness and lack of uniformity of ecological data. “There are all these species out there and so few of them are known in intimate detail, so any kind of ecological characterization, through no fault of ecologists, will be limited in accuracy and precision,” Funk says.

Nevertheless, the researchers decided to do the best they could with the information available. So they collected information from the published literature on three basic ecological variables: habitat, diet and size. Then they used this information to calculate the differences in ecological adaptation between the hundreds of pairs of related species in the original studies.

When they compared these differences in adaptation with the degree of reproductive isolation for each pair and then added them up, the researchers found that the overall association was positive with a surprisingly high level of confidence: The odds that the association is simply due to chance are only one in 250, substantially higher than the standard confidence level of one chance in 20 that scientists demand.

“The fact that the association is statistically significant despite the crudeness of our estimates suggests that the true biological association is very strong,” Funk says. “Darwin’s famous book was called ‘On the Origin of Species,’ but it was really about natural selection on traits rather than species formation. Since our study suggests that natural selection is a general cause of species formation, it seems that Darwin chose an appropriate title after all.”

[Omitted contact info which is at the end of the article.]


TOPICS: Culture/Society; Philosophy
KEYWORDS: bloodbath; crevolist; darwin; soupmyth; thatsurvivorssurvive
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To: CarolinaGuitarman
2) Not all dogs can/will breed with wolves.

Name one breed and site evidence.

1) That's artificial selection

So is the fruit fly experiment in the article and I believe the proof of most theory is done artificially in the laboratory.

3) This artificial selection is a great support for natural selection

I have a hard time seeing it that way. All of the evidence seems to point the other way.

1) Natural selection isn't defined by speciation. It's defined by adaptation to the environment. There is nothing about the fact that people can interbreed that goes against this. 2) A few thousand years is a very short time for speciation to happen. Isolation is not a guarantee that speciation will happen.

From the article.

In the last 20 years, studies of a number of specific species have demonstrated that natural selection can cause sub-populations to adapt to new environments in ways that reduce their ability to interbreed, an essential first step in the formation of a new species. However, biologists have not known whether these cases represent special exceptions or illustrate a general rule.

The article seem to suggest that the definitive proof of evolution would be the “sub-populations to adapt to new environments in ways that reduce their ability to interbreed” and that has always been my understanding of Darwin’s theory (remember his finches).

Darwin was well aware of selective breeding, far more than you. People have not been trying to make new species. And we have been at it for only a very short time even if we were. That being said, scientists have witnessed speciation.

Estimates I have read is that dogs have been domesticated for between 50 and 100,000 years that’s between 25 and 50 thousand generations. Specialized breeding would have started about 5 to 8 thousand years ago or 2.5 to 4 thousand generations ago with no change in the ability to breed with the root population.

Intension has nothing to do with it; according to Darwin’s theory dogs should be a new species and should not be able to breed with wolves.

41 posted on 02/24/2006 5:26:52 AM PST by Pontiac (Ignorance of the law is no excuse, ignorance of your rights can be fatal.)
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To: phantomworker

It was just "rhetorical" support. Sometimes things are just "koinkydinks" and not part of a chain of causality.


42 posted on 02/24/2006 5:28:55 AM PST by muawiyah (-)
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To: muawiyah
"Anyway, it's changes in the genome that make all the difference, and "natural selection" doesn't really explain that ~ it just describes it."

Natural selection is a two step process. Step one is the production of variation within a population. Step two is the selection (statistically) of the best adapted phenotypes from that population.

"For all anyone knows the bird flu may be the prime mover for transporting genes between species,..."

Or not.

"I think the Darwinian answer is, of course, that irrespective of how the genes get passed aroun, only those which benefit the species (if not the individual)..."

It's the individual, not the species. The individual is the basic unit of selection, though larger groups are also possible. That means an individual is selected not because it's traits will benefit the species, but because it out competed the others in it's population.
43 posted on 02/24/2006 5:29:29 AM PST by CarolinaGuitarman ("There is grandeur in this view of life...")
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To: muawiyah
But zebras are horses too

NO they are not

Zebras are more closely related to the Ass and can not successfully mate with the horse.

I think the virus theory may have merit.

44 posted on 02/24/2006 5:32:32 AM PST by Pontiac (Ignorance of the law is no excuse, ignorance of your rights can be fatal.)
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To: muawiyah

Interesting. If you knew anything about hypothesis testing, design of experiments, or statistical analysis, I don't think you would make a comment like that about this study.


45 posted on 02/24/2006 5:33:00 AM PST by phantomworker (You are the only person who defines you: Begins & ends with you-Go to the mirror & see for yourself)
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To: Pontiac
" Name one breed and site evidence."

Chihuahua and bull mastiff. You think that will happen naturally?

" I have a hard time seeing it that way. All of the evidence seems to point the other way."

Artificial selection shows the ability of selective pressures to change the morphology of a species to incredible lengths.


"The article seem to suggest that the definitive proof of evolution would be the “sub-populations to adapt to new environments in ways that reduce their ability to interbreed” and that has always been my understanding of Darwin’s theory (remember his finches)."

Evolution is not synonymous with natural selection.

"Intension has nothing to do with it; according to Darwin’s theory dogs should be a new species and should not be able to breed with wolves."

Nope, evolution doesn't say that at all.
46 posted on 02/24/2006 5:33:29 AM PST by CarolinaGuitarman ("There is grandeur in this view of life...")
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To: Pontiac
There are 3 basic divisions of domesticated dogs. We will be hearing shortly how far back they "divided", and that will pretty much pin down when domestication took place.

I thought it was quite interesting the way the "wild dogs" and "Indian dogs" in the Americas could be shuffled in and among an existing Eur-Asian group even though these animals "bark" much more like their African cousins.

The supposition is that originally dogs didn't bark much, if at all, and that may well have been the primary reason humans "selected" any particular wolfcub for domestication.

I wish they'd kept on that track ~ dogs down the street bark all the time.

47 posted on 02/24/2006 5:33:30 AM PST by muawiyah (-)
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To: ClearCase_guy
"I'll just note that the evos have a prepared list of insults in their pocket at all times."


Obviously there had to be more than one bowl of 'hot' primordial soup way back at the 'origin'.
48 posted on 02/24/2006 5:33:33 AM PST by Just mythoughts
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To: phantomworker
I worked many years very closely with one of the largest, most complex, and important statistical sampling systems in the world.

Let me assure you I've seen charleton's and true believers misuse statistics before, and this article falls in that category.

49 posted on 02/24/2006 5:37:25 AM PST by muawiyah (-)
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To: CarolinaGuitarman

If you can hold'em still, a chihuahua and bullmastif can breed quite successfully. Remember, with dogs it's just a matter of cycles and chemistry ~ they really aren't terribly selective, eh?!


50 posted on 02/24/2006 5:38:56 AM PST by muawiyah (-)
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To: Pontiac
I can think of a couple of on going experiments that refute the natural selection evolution theory quite well.

The first is dogs.

I'd pay to see you try to cause a successful union between a Great Dane and a teacup poodle.

The second is Man.

Man is amongst the slowest breeders in the world, and there has been no significant biological isolation of note for humans on this planet, by comparison to our leasurely breeding speed.

the third is horses.

Do you know what jennies and mules are? I suggest you look it up if you don't.

51 posted on 02/24/2006 5:40:36 AM PST by donh
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To: bvw
So Darwinists have some limited understanding of probability. Would that they apply it more broadly.

Creationoids don't have any understanding of probability or how to apply it, but think they do because the answers they make up support their religion.

52 posted on 02/24/2006 5:40:57 AM PST by WildHorseCrash
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To: CarolinaGuitarman
Ha ha. Typical Darwinist/liberal argument: "We are smarter/more educated and thus know more. You conservatives/creationists/Christians are dolts and can't understand/fathom/discern/feel what we are saying."

Of course the author might actually have that crystal ball showing him that this leaf beatle actually does evolve into a new species. In that case his claim that it was "in the process of transforming into a new species" could still be in concert with your statement that "Speciation is ONE end product of natural selection. It is not the only one."

If this crystal ball doesn't exist then he is making the typical macro-evo leap-of-faith and stating something he thinks/hopes/prays will happen.

Unlike you of course because you stated that speciation isn't the only result of natural selection. Bravo.

53 posted on 02/24/2006 5:42:37 AM PST by DesertSapper (I love God, family, country . . . and dead Islamofacist terrorists !!!)
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To: muawiyah
"If you can hold'em still, a chihuahua and bullmastif can breed quite successfully. Remember, with dogs it's just a matter of cycles and chemistry ~ they really aren't terribly selective, eh?!"

Not exactly a natural method, is it? And if it's a female chihuahua, she's in a lot of trouble.
54 posted on 02/24/2006 5:42:51 AM PST by CarolinaGuitarman ("There is grandeur in this view of life...")
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To: WildHorseCrash
"Creationoids don't have any understanding of probability or how to apply it, but think they do because the answers they make up support their religion."

LOL the evonoids designed probability, makes them gods.
55 posted on 02/24/2006 5:45:34 AM PST by Just mythoughts
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To: DesertSapper
"Ha ha. Typical Darwinist/liberal argument: "We are smarter/more educated and thus know more. You conservatives/creationists/Christians are dolts and can't understand/fathom/discern/feel what we are saying."

Sorry if the truth hurts. :)

" Unlike you of course because you stated that speciation isn't the only result of natural selection. Bravo."

Thanks. I was correct, you were wrong. Awfully big of you to admit your error. Most anti-evos aren't able to do that. :)
56 posted on 02/24/2006 5:45:37 AM PST by CarolinaGuitarman ("There is grandeur in this view of life...")
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To: CarolinaGuitarman
Well, true enough, but not all bull mastifs are all that well endowed.

But, when it comes to dogs, it's not all "natural".

Buddy of mine is a cat breeder. It's worse!

57 posted on 02/24/2006 5:47:23 AM PST by muawiyah (-)
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Comment #58 Removed by Moderator

To: muawiyah
Let me assure you I've seen charleton's and true believers misuse statistics before, and this article falls in that category.

What is your basis for this statement? Where is the methodology in this study flawed? Argument for argument's sake is a waste of time, dear muawiyah.

59 posted on 02/24/2006 5:51:42 AM PST by phantomworker (You are the only person who defines you: Begins & ends with you-Go to the mirror & see for yourself)
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To: bvw
Still, I guess, to mathematical idiots or Ascended Beings and Darwinists, 1/2 sounds passably close to 1/10 to the power of 10123. ;-)

???

What the article is saying is that if half of the other possible universes could still have lead to some form of life, even though formed with different properties than our own, then the odds are not 1 in one part in 1010123 (or whatever the number was supposed to be), but 1 in 2.

In other words, the Penrose calculation was about the particular set of physical properties of our universe, and not the chances of the existence of a universe with a set of properties which could still sustain life, even if those properties differed from our own. However, it is this later claim about life that some ID creationists are using Penrose to support.

60 posted on 02/24/2006 5:52:45 AM PST by WildHorseCrash
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