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RE: Evolution is inevitable - 4/3/2008 4:12:18 PM
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Bettawrekonize
Posts: 1204
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quote:
ORIGINAL: Agahnim
You’ve also already made it clear that the flying penguins would be convincing to you if those actually existed, but if this was a population recently discovered in Antarctica, nobody would have had the opportunity to directly observe the mutation occurring in their case, either. For these reasons, I don’t think having to observe all of the mutations directly is a reasonable requirement for what could be considered a falsification of Behe’s argument, as long as it’s possible to determine that they occurred in the past.
Well, we know that IC and SC systems do exist, so clearly it's possible to determine that they came to being sometime in the past. What we question is how. In order to know that we need to observe them come to being, not simply speculate that evolution is how they came to being. So such a falsification is a reasonable requirement.
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RE: Evolution is inevitable - 4/3/2008 4:26:41 PM
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Bettawrekonize
Posts: 1204
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quote:
ORIGINAL: Jhud
Actually, this would probably make a good test case; gene sequencing can give us an idea of how long the Vadoma have lived as a unique group, and how long ago the mutation which causes ectrodactyly arose in the population. Of course we are stuck with the literature which exists (which seems fairly meager in this case) so I am not sure this is a particularly good case to consider.
I think that a lot of information that may contradict UCD gets censored in general so it's possible that the information you are looking for maybe censored. Hopefully in the future the results maybe exposed through further research.
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Until this week I worked at the National Center for Science Education, where we oppose the ID/creationists and develop a finely-tuned sense of the sorts of things they will pluck from the literature and desperately portray as evidence that they aren't completely nuts. However, I am well aware that telling scientists to censor themselves to avoid giving creationists talking points is a non-starter, so hopefully my comments came out as being substantive rather than just the boring voice of orthodoxy.
http://www.biology-direct.com/content/2/1/21/comments
The inference here is that they, "develop a finely-tuned sense of the sorts of things they will pluck from the literature" in order to prevent it from being exposed.
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Even more horrifyingly, this leading genomic researcher (whose face is blacked out and voice disguised in the movie, to protect him from the destruction of his life and career by Darwinists) said that as much as 30% of the research in his field is shelved and never published because it might provide ammunition for “creationists.”
http://www.uncommondescent.com/expelled/expelled-at-biola-ben-stein-receives-the-phillip-johnson-award/#more-3176
I think that we need to get this research out and that people need to be much more aggressive about ensuring that committed naturalists are not able to discriminate against scientists, researchers, and research that may discredit materialism.
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RE: Evolution is inevitable - 4/3/2008 4:47:43 PM
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Jhud
Posts: 6772
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From: Lake Wobegon
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quote:
As I said, considering the amount of time it takes for this type of change to occur, I don’t think anyone can expect to have had the opportunity to observe an example of this directly within the ten years that people have been analyzing the genetics of animals. You’ve also already made it clear that the flying penguins would be convincing to you if those actually existed, but if this was a population recently discovered in Antarctica, nobody would have had the opportunity to directly observe the mutation occurring in their case, either. For these reasons, I don’t think having to observe all of the mutations directly is a reasonable requirement for what could be considered a falsification of Behe’s argument, as long as it’s possible to determine that they occurred in the past.
I think the paper itself might go into more detail about the steps through which the mutations accumulated; all I’ve linked to is a summary of the findings and a press release about them. Papers like this themselves aren’t generally publicly available, so I can’t link to one of them here. It’s often possible to access them through educational institutions, though.
Actually, I think the paper itself is available here:
Adaptive evolution of a duplicated pancreatic ribonuclease gene in a leaf-eating monkey
In my reading of it, the mechanism the paper considers (modification of a duplicate gene) is being considered in other research, I think recently with yeast – and with such a population one can certainly observe the genetic modifications as they occur. Indeed, it was this research that has exacerbated the debate over what is actually occurring or expected to occur - neofunctionalization, subfunctionalization, or subneofunctionalization.
Interestingly, gene duplication isn’t a particularly good mechanism for Darwinian evolution – because the whole purpose of duplicating a gene is to provide raw material for mutation, material that the organism isn’t currently depending on to live. Of course, once it is isolated that way, it also may no longer be necessary, and degrade, thus subfunctionalization. It also becomes unavailable to be subject to selection factors, because it is no longer being expressed in such a way for selection to act on.
For it to do as is suggested it did in the case of the douc langurs, that is duplicate, then modify in a positive way so as to take on enhanced functionality, it would have to do so not in the gradual way suggested by Darwin, but in a rather dramatically rapid way – which is why the researchers said it seemed to be acting in a ‘non-random’ way.
Personally, what I think what is more likely is that there existed an ancestral gene which coded for both enhanced digestion at a particular pH, and degrading RNA from the digestive bacteria. Those functions, rather than being a novel development in the duplicate gene, may actually represent a partition of functionality between the duplicate genes, which has been lost in other groups. Remembering that RNASE1 is more functional than RNASE1B, and that RNASE1B merely enhances the mode of digestion so as to make better use of leaves as a food source, we can surmise that the partition would allow a population of monkeys to lose the RNASE1B gene and it’s energy consuming function when other food sources were more widely available, because it’s activity then become unnecessary.
So an ancestral group may have portioned the functions between RNASE1 and RNASE1B duplication, whereupon both genes become subfunctional, albeit in different ways.
And whereas monkeys can generally ‘get along’ without RNASE1B as long as they can supplement their leafy diets, they simply dump RNASE1B where it’s unnecessary for an energy savings, much the way cave dwelling animal populations dump their eyes. In the case of the douc langurs, they may not have had access to such supplements – so they retained both forms of the gene, because it was worth it from and energy perspective.
This would explain how it appeared that multiple mutations arose so quickly in the douc langurs, contrary to predictions.
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As for the other two requirements you described, I can certainly come up with cases that meet each requirement individually, although I’m not sure I’ll be able to find a single case which meets all of them at once. In terms of a mutation giving an organism a completely novel functionality, one of my favorite examples is a mutation in a group of Japanese bacteria which gave them the ability to digest nylon. This is described a little here. Since the bacteria that have this mutation are unable to survive without nylon, they could not have existed before nylon was invented in 1935, meaning that this mutation must have occurred sometime within the past 73 years. As for mutations leading to the formation of new species, there are several examples of this listed at http://www.talkorigins.org/faqs/faq-speciation.html . You probably won’t be interested in the examples of this involving hybridization and polyploidy, but if you scroll further down there are several examples of observed speciation that don’t.
Yes, I have considered the ‘Nylon bug’ previously. I think the killer for me is that creating nylon eating bacteria can be done repeatedly, which suggests an inherent capability to me rather than a derived one. Not to mention that nylon eating bacteria readily return to their non-nylonase ways in the absence of nylon and presence of other food sources.
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I’m not sure whether you’ll consider it a falsification of Behe’s argument for there to be examples of each of these things happening individually, though. Does Behe claim that some of these occurrences aren’t possible at all? Or is his assertion that mutations can create entirely new functions; they can lead to the formation of new species; and several mutations can work together to cause an improvement in survivability, but what isn’t possible is for all three things to happen simultaneously?
I think Behe’s contention is best summed up as saying that the greater the number of unselected mutations required to produce an entirely novel function or structure, the less probable the occurrence of such a function or structure is, until such a probability approximates zero.
I think there are possible caveats to Behe’s contention.
The first is front-loading – that is that there is original (often latent) ancestral information that unfolds over time. I think there is increasing evidence that such exists.
The other is that there are inherent engineered mechanisms in organisms that can enhance capabilities on the fly – a lot of this is seen in gene regulation, that regulate certain capabilities (like digestion, or pumping out toxins) in response to selective stimuli. This is changing the way we see biological change that we previously considered the product of evolution – like antibiotic resistance.
_____________________________
Jack
“I mean to live my life an obedient man, but obedient to God, subservient to the wisdom of my ancestors; never to the authority of political truths arrived at yesterday at the voting booth”
William F. Buckley Jr. 1925-2008
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RE: Evolution is inevitable - 4/3/2008 5:10:59 PM
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Bettawrekonize
Posts: 1204
Joined: 4/17/2005
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quote:
ORIGINAL: Jhud
I think the killer for me is that creating nylon eating bacteria can be done repeatedly, which suggests an inherent capability to me rather than a derived one. Not to mention that nylon eating bacteria readily return to their non-nylonase ways in the absence of nylon and presence of other food sources.
I think that organisms were also designed such that simple mutations could yield benefits under certain circumstances because more complicated beneficial mutations are less likely to occur.
quote:
I think Behe’s contention is best summed up as saying that the greater the number of unselected mutations required to produce an entirely novel function or structure, the less probable the occurrence of such a function or structure is, until such a probability approximates zero.
Which is pretty much consistent with my contention.
< Message edited by Bettawrekonize -- 4/3/2008 5:21:01 PM >
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RE: Evolution is inevitable - 4/4/2008 5:27:38 PM
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Agahnim
Posts: 205
Joined: 2/27/2008
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quote:
Interestingly, gene duplication isn’t a particularly good mechanism for Darwinian evolution – because the whole purpose of duplicating a gene is to provide raw material for mutation, material that the organism isn’t currently depending on to live. Of course, once it is isolated that way, it also may no longer be necessary, and degrade, thus subfunctionalization. It also becomes unavailable to be subject to selection factors, because it is no longer being expressed in such a way for selection to act on.
For it to do as is suggested it did in the case of the douc langurs, that is duplicate, then modify in a positive way so as to take on enhanced functionality, it would have to do so not in the gradual way suggested by Darwin, but in a rather dramatically rapid way – which is why the researchers said it seemed to be acting in a ‘non-random’ way.
While I agree that duplicated genes typically don’t provide an advantage on their own, it’s important to remember that when a mutation is completely neutral with regard to an organism’s ability to survive, a few members of that species will always have it just as a result of random chance. To give a personal example, I’ve been diagnosed with autism, which most people consider to be the result of a mutation since it runs in families. Autism is found in somewhere between one and two percent of the population of the United States, not because it provides any kind of advantage, but because as long as it doesn’t provide a disadvantage natural selection won’t get rid of it entirely.
Something like a gene duplication, that also serves no advantage or disadvantage in survivability, would most likely be found in a similar percentage of most populations. Once a second mutation causes the gene to take on a new function that provides an advantage, though, natural selection will start to favor it.
quote:
Yes, I have considered the ‘Nylon bug’ previously. I think the killer for me is that creating nylon eating bacteria can be done repeatedly, which suggests an inherent capability to me rather than a derived one. Not to mention that nylon eating bacteria readily return to their non-nylonase ways in the absence of nylon and presence of other food sources.
The point I’m making is that it isn’t possible for this to be an ability the bacteria had before nylon was invented, because they can’t survive without nylon. The genetic code for this mutation has been sequenced—this is described here—and the mutation that gives the bacteria this ability is a frame shift that destroys the original functionality of the gene. This gene can give them the ability to digest their normal food, or with the mutation it can give them the ability to digest nylon, but it can’t do both.
The reason why these bacteria can switch so quickly between their normal and nylon-eating versions is probably because when changing from one of these states to another requires only a single mutation, every generation of bacteria will contain at least a few individuals that have it. So if you create an environment in which those individuals are the only ones capable of surviving, they’ll repopulate their habitat with bacteria that have it fairly quickly.
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I think Behe’s contention is best summed up as saying that the greater the number of unselected mutations required to produce an entirely novel function or structure, the less probable the occurrence of such a function or structure is, until such a probability approximates zero.
Once a mutation or series of mutations spreads throughout a population and becomes the norm for them, as has happened in some of the instances of speciation described at Talk.Origins and appears to also have happened in the leaf-eating monkeys, what is there that prevents additional mutations from occurring that cause new modifications? Or is Behe’s argument that there are structures and functions that can’t exist without multiple mutations, and each individual mutation won’t be favored by natural selection because on its own it isn’t able to provide an advantage? If it’s the second one, this sounds like it’s just a retread of his “irreducible complexity” argument.
Based on what I’ve read about this book in some online analyses of it, it sounds like this is what he’s saying. There’s one such article at http://www.sciencemag.org/cgi/content/full/316/5830/1427 that I think you should read, because it describes several examples of experimental data that go against Behe’s assertions.
Incidentally, I think it might be a good idea for you to debate about this topic at Christian Forums—genetics is definitely not my specialty, so there’s a limit to how much detail I’ll be able to go into while discussing it with you, but several of the members there are much more knowledgeable about it than I am.
< Message edited by Agahnim -- 4/4/2008 6:26:11 PM >
_____________________________
"I like your Christ. I do not like your Christians. Your Christians are so unlike your Christ." --Mahatma Gandhi
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RE: Evolution is inevitable - 4/7/2008 4:08:42 PM
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Bettawrekonize
Posts: 1204
Joined: 4/17/2005
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quote:
ORIGINAL: Agahnim
The point I’m making is that it isn’t possible for this to be an ability the bacteria had before nylon was invented, because they can’t survive without nylon.
A:
If they, "return to their non-nylonase ways in the absence of nylon and presence of other food sources." then they can survive without nylon.
B:
They can survive without nylon before being exposed to nylon.
quote:
This gene can give them the ability to digest their normal food, or with the mutation it can give them the ability to digest nylon, but it can’t do both.
Not both at once. Perhaps it can frame shift back.
C:
Even if, "they can’t survive without nylon" that's no reason to say that, "it isn’t possible for this to be an ability the bacteria had before nylon was invented." Perhaps the designer had to make trade offs. We would have to know the intent of the designer to know this.
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The reason why these bacteria can switch so quickly between their normal and nylon-eating versions is probably because when changing from one of these states to another requires only a single mutation, every generation of bacteria will contain at least a few individuals that have it.
This is exactly what Jhud is arguing. My contention is that the designer may have designed it this way. Read my post above. This could be the mechanism behind the "inherent capability."
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Based on what I’ve read about this book in some online analyses of it, it sounds like this is what he’s saying. There’s one such article at http://www.sciencemag.org/cgi/content/full/316/5830/1427 that I think you should read, because it describes several examples of experimental data that go against Behe’s assertions.
They're not understanding Behe's argument. Behe argues that, in the case of IC systems, many beneficial mutations would have to occur at once to build the system since each specific mutation would not benefit the organism. In such a situation (such as the flagellum) it is highly unlikely for this to happen. He is not arguing that beneficial mutations can't cumulate whatsoever (though the harmful mutations would have cumulated more by then since harmful mutations are more likely than beneficial ones) he is arguing that in certain systems (such as the flagellum), many mutations would be necessary for the system to be beneficial (and any single mutation closer to a flagellum would not be beneficial). The whole system must be in place for the system to benefit the organism, if one has a flagellum that doesn't work it is only a hindrance to the organism. I also notice how your site takes behe out of context.
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Behe begrudgingly allows that only "rarely, several mutations can sequentially add to each other to improve an organism's chances of survival." Rarely? This, of course, is the everyday stuff of evolution. Examples of cumulative selection changing multiple sites in evolving proteins include tetrodotoxin resistance in snakes (3), the tuning of color vision in animals (4), cefotaxime antibiotic resistance in bacteria (5), and pyrimethamine resistance in malarial parasites (6)--a notable omission given Behe's extensive discussion of malarial drugresistance.
http://www.sciencemag.org/cgi/content/full/316/5830/1427
Aside from the fact that your site doesn't even cite the quote, even if that's a valid quote from Behe, it doesn't seem like Behe is referring to cumulative selection. He is referring to multiple mutations creating an IC system all at once (an IC system being a system that would require each part in place to be useful). While it is possible for more than one mutations to create an interdependent benefit, such a situation is rare (but that's not to say it never happens), and the more simultaneous mutations that are required for a benefit to occur, the less likely it will occur. In the case of the flagellum, all the parts must be in place and functional for the flagellum to be useful and the chances of such a system emerging as a result of simultaneous (random) mutations are very small.
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Incidentally, I think it might be a good idea for you to debate about this topic at Christian Forums—genetics is definitely not my specialty, so there’s a limit to how much detail I’ll be able to go into while discussing it with you, but several of the members there are much more knowledgeable about it than I am.
If they want to come here, they are free to. Invite them. I have been to other forums where evolutionists are permitted to cuss at those who oppose them and resort to personal attacks and many people prefer to stay here where such tactics are banned (even though the TOS on other forums often disallow such behavior, often times the TOS are not enforced. Here, they are).
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Once a mutation or series of mutations spreads throughout a population and becomes the norm for them, as has happened in some of the instances of speciation described at Talk.Origins and appears to also have happened in the leaf-eating monkeys
They are speculating this happened in the leaf-eating monkeys, this has not been observed. This is speculated to have occurred millions of years ago. I already explained why such speculation is not a reasonable standard of proof (post 26) and any site that speculates existing systems were the result of evolution is not providing evidence that such systems occurred via evolution. The existence of a system is not evidence that it evolved.
< Message edited by Bettawrekonize -- 4/7/2008 5:10:12 PM >
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RE: Evolution is inevitable - 4/8/2008 12:19:41 AM
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drj11
Posts: 462
Joined: 3/29/2008
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quote:
ORIGINAL: Bettawrekonize
A:
If they, "return to their non-nylonase ways in the absence of nylon and presence of other food sources." then they can survive without nylon.
B:
They can survive without nylon before being exposed to nylon.
Its natural selection at work. Generally new traits like the nylon eating, and antibiotic resistance etc, come at a metabolic cost. It takes more energy for those organisms to exist. So when the selective pressure is removed.. the one that let the bacteria with the adaptation thrive, the bacteria without the ability are "more fit" in the current environment, and are able to more successfully reproduce. The others get naturally selected away. Hence, the flip flopping back and forth.
< Message edited by drj11 -- 4/8/2008 12:51:23 AM >
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RE: Evolution is inevitable - 4/9/2008 12:32:52 AM
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Bettawrekonize
Posts: 1204
Joined: 4/17/2005
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quote:
ORIGINAL: drj11
Its natural selection at work. Generally new traits like the nylon eating, and antibiotic resistance etc, come at a metabolic cost. It takes more energy for those organisms to exist. So when the selective pressure is removed.. the one that let the bacteria with the adaptation thrive, the bacteria without the ability are "more fit" in the current environment, and are able to more successfully reproduce. The others get naturally selected away. Hence, the flip flopping back and forth.
None of which negates anything that I said.
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RE: Evolution is inevitable - 4/9/2008 11:53:39 PM
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cybrjewls
Posts: 1392
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Hello! That what the BBC freemasons are doing. They are making fun of those that are so 'scientifically' blind that they could not discern the black markings on the back of some penguins. It is such a tribute to the invisible hand of 'natural selection' to notice that black does not blend in with the snow, and does not offer any competitive advantage to the penguin in its environment. Apparently, the masons are so jealous over God that they don't want the scientists that are employed to be believers necessarily. It makes the club all that more powerful.
Freedom in 'Gallileo' land has never looked so dominated.
quote:
ORIGINAL: Agahnim
quote:
I would say hyper-skeptical; the BBC is an esteemed news organization and it's commitment to scientific coverage is impeccable; do you really think they would decieve the public this way?
Ordinarily no, but I’ve seen organizations that are just as reputable as BBC still fall prey to the desire to play pranks on people for April Fool’s Day.
It’s odd that our normal roles would be reversed like this, where I’m the one disputing the validity of a line of evidence for evolution that you find convincing. But as much as I’d like for you to accept evolution, I would hate for the thing that ends up convincing you to turn out to be a joke.
< Message edited by .prophetica. -- 4/10/2008 12:00:21 AM >
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