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Author Topic:   Beneficial Mutations Made Simple
IrishRockhound
Member (Idle past 4436 days)
Posts: 569
From: Ireland
Joined: 05-19-2003


Message 1 of 52 (312344)
05-16-2006 7:48 AM


I thought it was, perhaps, time to take a look at this subject again after reading a post by romajc in another thread.
Beneficial mutations - traditionally creationists assert that they do not occur, as far as I'm aware. Their position is that all mutations are harmful and adversely affect a creature's survivability, or neutral and do nothing - part of the notion that creatures are "degrading" since the Fall of Man, and cannot be improved as such.
Of course, evolution is simply a compilation of many, many beneficial mutations which, after a very long time, alter a creature to the extent that we may classify it as a seperate species. One single mutation may be very minor, but it is the sum of all the mutations that makes evolution - little steps along a path adding up to miles and miles travelled, if you will - and there is no concieveable limit to it as long as we can show that beneficial mutations occur constantly.
So - it may be beneficial () to creationists if we list some simple examples of such mutations, and explain why they are so and why they will be passed to the next generation.
My example: My mother is missing four molars, so she has only one set per jaw instead of two. I have inherited this mutation, and I am missing two wisdom teeth as well. It is beneficial because my teeth are very easy to clean, hence my teeth are very healthy and I have no fillings or anything. It has not effected my ability to eat at all.
Assume for a minute that I am a prehistoric human. As my teeth are very healthy due to my mutations, I will retain them longer than someone without those mutations - so I can eat better for longer than them and will probably live longer as a result. Let's assume as well that my tribe find teeth aesthetically pleasing in a mate - I am more likely to find a mate than someone toothless. Both these environmental conditions will give me a higher chance to reproduce and pass on my mutations.
In modern times those conditions are absent, so my chance to reproduce is not affected per se. But having healthy teeth is a nice bonus. Bear in mind that this is an illustrative example and probably isn't entirely accurate, but it does describe how beneficial mutations are selected for and passed on.

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AdminWounded
Inactive Member


Message 2 of 52 (312345)
05-16-2006 8:01 AM
Reply to: Message 1 by IrishRockhound
05-16-2006 7:48 AM


Does this need a topic all of its own? We already have a Mutations Made Easy thread. Is there a reason this wouldn't be a suitable addendum to that?
TTFN,
AW

This message is a reply to:
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AdminWounded
Inactive Member


Message 3 of 52 (312362)
05-16-2006 9:11 AM
Reply to: Message 2 by AdminWounded
05-16-2006 8:01 AM


In the light of a plea from Quetzal about the bogdownedness of the other thread lets give this one a fair crack of the whip.
TTFN,
AW
Edited by AdminWounded, : No reason given.

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AdminWounded
Inactive Member


Message 4 of 52 (312363)
05-16-2006 9:11 AM


Thread moved here from the Proposed New Topics forum.

  
Wounded King
Member
Posts: 4149
From: Cincinnati, Ohio, USA
Joined: 04-09-2003


Message 5 of 52 (312368)
05-16-2006 9:22 AM
Reply to: Message 1 by IrishRockhound
05-16-2006 7:48 AM


Some recent research has shown that at least one mutation in the gene coding for Lipoprotein Lipase (LPL) produces a protein which is prematurely truncated and which appears to be more efficient in preventing atherosclerosis and cardiovascular disease than wildtype LPL (Rip, et al., 2006).
I would not typically have expected a gene like this to be particularly beneficial as I would associate it with a later stage of life than when most reproduction is occurring. However perhaps modern dieat and the increase in obesity, or the fact that many people are having children later in life have allowed this to become a target for selection.
Having said that the prevalency of the mutation, carried by ~20% of the population, suggests that its origins are considerably more ancient than the 20th century when the current lifestyle factors would have been relevant. Once again it is all to easy to make up ad hoc hypotheses which could explain some aspects of a phenomenon.
TTFN,
WK

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jar
Member (Idle past 394 days)
Posts: 34026
From: Texas!!
Joined: 04-20-2004


Message 6 of 52 (312407)
05-16-2006 10:52 AM
Reply to: Message 1 by IrishRockhound
05-16-2006 7:48 AM


There are many, many such examples. One deals with Atherosclerosis, hardening of the arteries, a major cause of heart problems and perhaps even related to the aging process and thinking. It appears that there is a gene mutation that reduces the incidence of Atherosclerosis. You can read about it here.

Aslan is not a Tame Lion

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EZscience
Member (Idle past 5154 days)
Posts: 961
From: A wheatfield in Kansas
Joined: 04-14-2005


Message 7 of 52 (312464)
05-16-2006 1:41 PM
Reply to: Message 1 by IrishRockhound
05-16-2006 7:48 AM


Context matters...
Both the context of the organism in which the mutation occurs, and the environmental context in which it finds itself.
Labelling a mutation 'beneficial' is a very loaded statement.
It might be benficial in one context, but not in another.
The same can be said for some deleterious mutations - they are not always deleterious in all contexts.
For example, a mutation for pyrethroid resistance in whiteflies is only beneficial to the whitefly population when it is useful for surviving heavy insecticide applications. When more effective biological controls are established in greenhouses, the incidence of the resistance gene decreases. This is because it is no longer 'beneficial', but is in fact 'less adaptive' that its pyrethroid-susceptible analogue in the absence of the selection pressure.
Also, we need to remember that many mutations are neutral or functionally equivalent, at least until the population's adaptive topography changes...

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Percy
Member
Posts: 22392
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.3


Message 8 of 52 (312499)
05-16-2006 3:23 PM
Reply to: Message 1 by IrishRockhound
05-16-2006 7:48 AM


IrishRockHound writes:
Beneficial Mutations Made Simple
So who made relative?
Sorry, couldn't help it.
--Percy

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IrishRockhound
Member (Idle past 4436 days)
Posts: 569
From: Ireland
Joined: 05-19-2003


Message 9 of 52 (313138)
05-18-2006 9:11 AM
Reply to: Message 8 by Percy
05-16-2006 3:23 PM


Everyone's a comedian.
And of course environmental factors are important in whether the mutations are beneficial or not. This is why I asked that people explain why a particular mutation would be selected for - to explain the conditions that cause it to be beneficial.
No creationists want to step in here, ask questions?

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jar
Member (Idle past 394 days)
Posts: 34026
From: Texas!!
Joined: 04-20-2004


Message 10 of 52 (313168)
05-18-2006 10:37 AM
Reply to: Message 9 by IrishRockhound
05-18-2006 9:11 AM


natural Selection is like Politics...
it's all local.
This is why I asked that people explain why a particular mutation would be selected for - to explain the conditions that cause it to be beneficial.
This is a very important point and one that IMHO is not explained often enough. There really is more than one mechanism in evolution. Mutations are not beneficial, or harmful in and of them selves. It's only the outcome that gives us any indication of benefit or harm.
Likewise, Natural Selection can only be understood based on the results. Whether the outcome is beneficial or harmful depends on the point of view of the observer.
We realy need to see the system as in constant flux, constant change. We are always looking back at a history, looking at what happened. Not only do the conditions change, but any given set of conditions will be both beneficial for some and harmful to others. Just as on the mutation side, Natural Selection is only harmful, beneficial or neutral in relation to the particular point of view of the observer.

Aslan is not a Tame Lion

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Hyroglyphx
Inactive Member


Message 11 of 52 (313185)
05-18-2006 12:07 PM
Reply to: Message 1 by IrishRockhound
05-16-2006 7:48 AM


Beneficial mutations - traditionally creationists assert that they do not occur, as far as I'm aware.
Hox proteins are thought by some to be the vehicle driving beneficial mutations. For instance, an ongoing experiment on the drosophila (fruit fly) have been conducted for over 80 years. Numerous scientists have bombarded these fruit flies with X-ray radiation, among other techniques, in order to mutate them. Well, it worked. In fact, it worked remarkably well. They were able to produce offspring with eyes missing and wings growing out of their heads. Here is the point: No bionic fruit fly was ever the bi-product of these experiments. (No dragonflies, houseflies, horseflies, butterflies, were ever bioengineered . . Just fruit flies and lots of them). Of those that actually survived essentially produced monstrosities with horrible deformities that certainly would have eliminated them in the wild. Even more damning, the fruit fly is molecularly very simple in relation to that of a human. What is worse, their lifespan is not even a thousandth to that of the average human lifespan. What does this mean? Essentially, it means that the fruit fly has the physical ability to evolve more readily than that of a human being. The fruit fly is relatively simple with a genome, composed of four pairs of chromosomes of about 13,000 genes. Aside from this, they breed at a much quicker rate. So then, surely in 80 to 90 years of experimentation, their generations would be into the hundreds of thousands. Compare that figure to humans. In 80 or 90 years, how many generations have come out of your immediate family? Most likely, in your family, three generations and maybe four generations in that amount of time. If ever there were a prime candidate for macroevolution, the Drosophilia would be it, and yet, nothing even comparable to a new specie has ever evolved. It is unsurprising that their tests are still inconclusive, at best.
PBS had a special on such mutations and showed an extra pair of wings on a fly and silently praised it. This of course was their tacit way of proving macroevolution. They neglected to mention that they were a hindrance for flying because no musculature was attached to it. It was as close to a harmful mutation as anything I could think of. The extra set certainly didn't aid in its flight. Polyploidy, gene duplication, or insertions do not adequetly explain any sort of macroevolutionary process. Some biologists believe that appendages like the insect wings and the proboscis of a mosquito must have evolved from a spare leg. For starters, a ”proboscis’ on a mosquito is the needle-like structure that jabs the host to extract blood. (I’m sure many of you are intimately acquainted with the proboscis of a mosquito). They somehow have just guessed that a ”spare leg’ can inexplicably become a functioning proboscis. That is so unfounded that I'm not sure a retort is even worth it.
In summary, evolution relies on mutation and hopes that it will be beneficial. It has to rely on this because natural selection and genetic drift both need a gene pool from which to select from or drift within.

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Coragyps
Member (Idle past 735 days)
Posts: 5553
From: Snyder, Texas, USA
Joined: 11-12-2002


Message 12 of 52 (313192)
05-18-2006 12:35 PM
Reply to: Message 11 by Hyroglyphx
05-18-2006 12:07 PM


and showed an extra pair of wings on a fly and silently praised it.
How did they do that, nem?

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fallacycop
Member (Idle past 5520 days)
Posts: 692
From: Fortaleza-CE Brazil
Joined: 02-18-2006


Message 13 of 52 (313194)
05-18-2006 12:41 PM
Reply to: Message 11 by Hyroglyphx
05-18-2006 12:07 PM


ARGUMENT OUT OF INCREDULITY
Your whole post is one long argument out of incredulity. It amounts to nothing.

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Wounded King
Member
Posts: 4149
From: Cincinnati, Ohio, USA
Joined: 04-09-2003


Message 14 of 52 (313195)
05-18-2006 12:41 PM
Reply to: Message 11 by Hyroglyphx
05-18-2006 12:07 PM


Hox proteins are thought by some to be the vehicle driving beneficial mutations.
These 'some' are presumably people who have no idea what the hell they are talking about. The Hox genes are important in body patterning and are thopugh to have an important role in the evolution of differeing body plans but to describe them as 'the vehicle driving beneficial mutations' just suggests you haven't the faintest familiarity with any of the science and are just parroting bullshit from some equally ill informed website.
The mutational screens you are talking about, presumably along the lines of the seminal work of Nusslein-volhard and Weischaus, were specifically designed to allow the identification of mutations which were embryonically lethal or otherwise easily scorable. If this isn't the sort of work you were talking about then maybe you should provide some references.
The types of mutagenesis used are also massively crude, such as mutagenic chemicals or exposure to gamma rays, the idea is to damage the dna in order to identify regions which are important in a process not to generate mutations in a way analagous to what goes on in vivo
Almost all such screens look for easily scored phenotypic characteristics, i.e. legs substituted for antennae, no eyes, severe losses or changes in character of limb, early death or failure to hatch. The only way to identify a 'bionic' fly would be to follow it through a breeding population to find out that it had improved fitness. You can easily see a lethal mutation which will never live to reproduction, or severely impair it, but it is much harder to identify one which will increase reproductive success merely by eyeballing an embryo.
PBS had a special on such mutations and showed an extra pair of wings on a fly and silently praised it. This of course was their tacit way of proving macroevolution. They neglected to mention that they were a hindrance for flying because no musculature was attached to it. It was as close to a harmful mutation as anything I could think of
Once again you miss the point. The mutations leading to a 4 winged Drosophila have never been suggested to be beneficial mutations, rather they are seen as consistent with the theory that the haltere is a derived wing and that the Diptera (2 winged flies) evolved from an ancestor with 4 wings. When going from a wing to the haltere the loss of the indirect flight muscles in the 3rd thoracic segment would be inconsequential, but obviously that loss presents a severe barrier to reverting back to a fully functioning wing.
The rest of your post just seems to be pure hand waving explanation. Your science just seems to be pure garbage, you should really provide some evidence if you expect anyone to think they aren't just your own deranged imaginings.
No one says that the probioscis evolved from a 'spare leg' and the work suggesting that there are homologies between the 2 structures could not be further from guessing (Abzhanov , et al., 2001), but I suppose you would have to actually understand any of it to know that, and you clearly don't. If you have even read any of it that is, which I sincerely doubt.
In summary, evolution relies on mutation and hopes that it will be beneficial. It has to rely on this because natural selection and genetic drift both need a gene pool from which to select from or drift within.
Practically the only remotely accurate thing in your entire post.
TTFN,
WK
Edited by Wounded King, : presentation of additional information

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Replies to this message:
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mr_matrix
Inactive Member


Message 15 of 52 (313597)
05-19-2006 5:13 PM


Tales of Mutations
It is funny to see evolutionists talking about mutations and giving them great credits. All I saw in these posts (the ones that defend mutations and evolution) is just imaginary tales of a mutation having a benifit. This is because that is what evolution is all about: if your in the mood, make up a scenario and publish it and claim it to be "scientific". All these tales of mutations having benifit are imaginary and with no logic or evidence.
Lets look at the DNA, it is a very complex structure that functions almost perfectly on its own, and a mutation is just an accident that damages the DNA and harms the organism. What good may come from this unconsious and random intervention in the complex system of the DNA? Some of you go as far as to claim that mutations can be useful if you use them well. But, has anybody observed a benefitial mutation that accounts for evolution of defferent species? NO.
A mutation is like an earthquake that hits a building. Believing in benefitial mutations is like believing that an earthquake can improve a building and not damage it. What good might come from cancer, down syndrome, albinism, fibrosis, and other mutations. Maybe you sould have one of these mutations and then see if you can make advantage out of them.
In short, a benifit from a mutation is just an evolutionary fantasy tale.
Edited by mr_matrix, : No reason given.

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