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Author Topic:   Has natural selection really been tested and verified?
Coyote
Member (Idle past 2105 days)
Posts: 6117
Joined: 01-12-2008


Message 16 of 302 (536322)
11-21-2009 6:00 PM
Reply to: Message 11 by Granny Magda
11-21-2009 4:15 PM


Re: Minor corrections
You are correct; two articles in the same journal with virtually identical titles published in the same year.
And I missed the difference in authors.
Not good! I am usually more careful than that. I apologize for the error.

Religious belief does not constitute scientific evidence, nor does it convey scientific knowledge.

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 Message 11 by Granny Magda, posted 11-21-2009 4:15 PM Granny Magda has not replied

Bolder-dash
Member (Idle past 3629 days)
Posts: 983
From: China
Joined: 11-14-2009


Message 17 of 302 (536328)
11-21-2009 7:01 PM
Reply to: Message 5 by RAZD
11-21-2009 11:58 AM


Re: Yes.
Thank you for your thorough reply and tips RAZD.
I have to say, I don't think we are even close to answering the question however. The supposition made by the magazine editor (not by me)was that Darwin's idea of natural selection has been tested to be the driving force of evolutionary change (including of course changes in body structures, and living systems, etc).
So far it seems the "tests" you and others have mentioned as evidence, provide nothing in the way of showing that it was " Darwin's natural selection" that caused this evolutionary changes._In fact what they all demonstrate is that a change was "needed" in a population and the change occurred. That is quite a different thing from showing that random mutations slowly drifted through the populations along with every other kind of random mutation, causing the change.
One of the studies cited by another poster deals with a population in Papua New Guinea developing an amazingly quick resistance to a fatal brain disease called kuru:
quote:
"Lead author Professor John Collinge, Director of the MRC Prion Unit said:
It’s absolutely fascinating to see Darwinian principles at work here. This community of people has developed their own biologically unique response to a truly terrible epidemic. The fact that this genetic evolution has happened in a matter of decades is remarkable."
It is kind of funny that one would cite a population of people developing a resistance to disease in a few decades as evidence that Darwin's theorized process of slow gradual change, based on random mutations caused these resistances. This was a random mutation that just so happened to crop up exactly in a population that was experiencing the disease, in exactly the right time(down to the decade) that the population was being exposed to the pressure? That is some serious good fortune. I wonder who that 'one" individual is who happened to be around at just the right time to father the entire population of children and pass on the resistance is? I guess the entire population can be traced by to one very prolific and possibly still alive reproducer. That is one very inbred society. The entire population was fathered by one man (or woman), who might even still be alive!
Furthermore, to really provide more evidence that it truly is random mutations, and natural selection of populations dying out that didn't receive this beneficial mutation, I would think you would need to show something like a test in which other individuals within this population happened to have resistance to all kinds of other fatal diseases, which they have never even been exposed to, which they also received through a random mutation-like some might be resistant to bubonic plague, or Kluver-Bucy Syndrome, or the Ebola virus or Lou Gehrig's disease even though they have never seen or heard of these.
The other studies mentioned, such as Galapagos finches and Peppered moths, these are all old stories about evolution, but in what way do they test or show the randomness of the mutations and that caused these shifts in populations?
And also, since in cases like the Galapagos finches, the populations oscillate back to their original forms of shorter beaks, under different environmental conditions, we have to show the same processes happening twice-first a random mutation causes longer beaks to sprout and then those get chosen within the population, and then later wouldn't you know it, another "random" mutation comes along and the exact same slow weeding out process of mates choosing the best beak sizes happens again; and fortuitously the need for a certain beak size remains the single most important consideration for mate selection over the vast spaces of time that natural selection requires. Quite amazing.
Or even more amazing still, we have a entire list of traits we are selecting for over many many years of generations, overlapping each other- lung capacity, tail size, genital size, coloration, chirping sound, eyesight, nest building techniques, proper digestive gland sizes, and on and on..and each and every one of these needs is remaining constant long enough after all these random mutations occurred to eventually trickle their way through the selection process. So each time a beak size is being chosen for, all of these other criteria, and about 100,000 = others are also being selected for. It must be a tough choice for a pretty female finch to decide.

This message is a reply to:
 Message 5 by RAZD, posted 11-21-2009 11:58 AM RAZD has replied

Replies to this message:
 Message 18 by Granny Magda, posted 11-21-2009 8:53 PM Bolder-dash has replied
 Message 19 by CosmicChimp, posted 11-21-2009 10:22 PM Bolder-dash has replied
 Message 20 by RAZD, posted 11-21-2009 10:55 PM Bolder-dash has replied
 Message 27 by lyx2no, posted 11-22-2009 9:30 AM Bolder-dash has replied

Granny Magda
Member
Posts: 2462
From: UK
Joined: 11-12-2007
Member Rating: 4.0


(1)
Message 18 of 302 (536332)
11-21-2009 8:53 PM
Reply to: Message 17 by Bolder-dash
11-21-2009 7:01 PM


Re: Yes.
Hi BD, just a brief note. You say;
That is quite a different thing from showing that random mutations slowly drifted through the populations along with every other kind of random mutation, causing the change.
and;
It is kind of funny that one would cite a population of people developing a resistance to disease in a few decades as evidence that Darwin's theorized process of slow gradual change, based on random mutations caused these resistances.
Darwin never knew about random mutation. It had not been discovered in his day. On the Origin of Species never uses the phrase "random mutation" and when using the word "mutation", Darwin uses it only in a general sense, comparable in meaning to "change" or "variance". Darwin was unaware of the exact cause behind inheritable characteristics and their variation, only that whatever the cause, it s results were guided by natural selection.
If you want to insist on a purely "Darwinian" model (i.e. a model that Darwin himself would have put forward during his time), you should not be talking about random mutation, because he would not have recognised the concept.
For the record, what ideas Darwin had about heritability and variation were largely wrong. This has been known for decades.
Mutate and Survive

"A curious aspect of the theory of evolution is that everybody thinks he understands it." - Jacques Monod

This message is a reply to:
 Message 17 by Bolder-dash, posted 11-21-2009 7:01 PM Bolder-dash has replied

Replies to this message:
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CosmicChimp
Member
Posts: 311
From: Muenchen Bayern Deutschland
Joined: 06-15-2007


Message 19 of 302 (536335)
11-21-2009 10:22 PM
Reply to: Message 17 by Bolder-dash
11-21-2009 7:01 PM


Bolder-dash writes:
...
It is kind of funny that one would cite a population of people developing a resistance to disease in a few decades as evidence that Darwin's theorized process of slow gradual change, based on random mutations caused these resistances.
...
You seem to be genuinely surprised that "Darwin's theorized process" could account for the prevalence of a newly discovered variation of the prion protein gene. The variation seems to give at least partial protection from kuru. I would expect to find-out that this protective polymorphism would be disproportionately represented in the human population located exactly where past cultural practices existed that propagated kuru.
Conversely, if the protective variation were not present in a local population, I would expect that it had died out as well as the dangerous cultural practice; or that kuru had never been a significant enough causal agent for the gene variant being selected for at any instantiation.
Added by edit {ABE}: Why do you think that this polymorphism should not be in a global location where it would be selected for? Is your objection having more to do with this variation of an existing gene being the cause of the protection or are you concerned about when how and why the mutation occurred in the first place?
Edited by CosmicChimp, : clarity
Edited by CosmicChimp, : added a question at bottom.
Edited by CosmicChimp, : apostrophe usage and editing for clarity

This message is a reply to:
 Message 17 by Bolder-dash, posted 11-21-2009 7:01 PM Bolder-dash has replied

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RAZD
Member (Idle past 1404 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


(2)
Message 20 of 302 (536336)
11-21-2009 10:55 PM
Reply to: Message 17 by Bolder-dash
11-21-2009 7:01 PM


Re: Yes ... now the evasion starts?
Thanks Bolder-dash,
The supposition made by the magazine editor (not by me)was that Darwin's idea of natural selection has been tested to be the driving force of evolutionary change (including of course changes in body structures, and living systems, etc).
Now we have a little more description of what you are meaning by "evolutionary change" and I have to note that changes in "body structure and living systems" are actually the accumulation of many smaller changes, taking place over multiple generations, so no, you are not going to see this kind of change in one study. This is similar to asking to see mountains rise and erode in the course of one or two years.
What the author of the article in Discover meant is not shown here - we have no quotes from the article itself, and unfortunatey you did not provide a link, the title of the article, or even the date when your article was published. This makes it difficult to reply to what "supposition made by the magazine editor" involves.
Going to the Discover Magazine website and doing a search for "Natural Selection Darwin" gives me this link:
We All Live in Darwin's World
Survival of the fittest is helping us understand not only the origin of species but also love, politics, and even the cosmos.
by Karen Wright
From the March 2009 issue, published online February 11, 2009
and this one:
Discover Interview E.O. Wilson
Biology's chief provocateur explores the evolutionary origins of cooperation, warfare, and the tribal mind
by Richard Conniff, Photography by Gerald Forster
From the June 2006 issue, published online June 25, 2006
But the content of these articles is nothing like what you are saying: can you provide a citation for the article in question?
Note further, that Discover Magazine is a "popular science" magazine, the articles are written by journalists not scientists, the articles are edited for popular appeal, and it not a peer reviewed journal, so it is not a reliable source for actual science. It can be a fun read, and if you are truly interested in a topic covered by the magazine, then you should follow the references
So far it seems the "tests" you and others have mentioned as evidence, provide nothing in the way of showing that it was " Darwin's natural selection" that caused this evolutionary changes._In fact what they all demonstrate is that a change was "needed" in a population and the change occurred.
Curiously, these are sufficient within the science of biological evolution, as the science is understood and used by the scientists. If you disagree, then you have a problem with learning the proper terminology to discuss this.
Evolution in general, and natural selection in particular, does not manufacture what is "needed" -- this is false thinking, and nobody in any of the biological sciences suggest this, nor did Darwin.
Evolution is a response mechanisms: the ecology changes, and
  • if the change is sever enough the species will go extinct,
  • if some small percentage of the population survives due to having certain traits in the surviving individuals that the majority did not have, then the traits, and only the traits, of the surviving individuals will be passed on to the next generation,
  • if the change is moderate such that most individuals survive, then there will be more of a mixture of surviving traits to be passed on to the next generation
What the process of survival and reproduction accomplishes is surviving and breeding individuals that are better at surviving and breeding than other individuals within a breeding population, and thus the hereditary traits they have become shared to a greater extent within the population.
Natural selection operates on the existing traits within the existing population to select the traits that are best suited to the ecology around the individuals.
That is quite a different thing from showing that random mutations slowly drifted through the populations along with every other kind of random mutation, causing the change.
Mutations don't "drift through the populations" - you are not understanding the process that is involved.
See Berkeley University - Evolution 101
and UMich - Evolution and Natural Selection
To see what evolutionary biologists say, rather than populist journalists and editors.
This was a random mutation that just so happened to crop up exactly in a population that was experiencing the disease, in exactly the right time(down to the decade) t
You are misreading this article. The beneficial mutation existed before the epidemic occurred:
quote:
Scientists from the MRC Prion Unit, a national centre of excellence in prion diseases, assessed over 3000 people from the affected and surrounding Eastern Highland populations, including 709 who had participated in cannibalistic mortuary feasts, 152 of whom subsequently died of kuru. They discovered a novel and unique variation in the prion protein gene called G127V in people from the Purosa valley region where kuru was most rife.
Those who participated in the cannibalistic mortuary feasts and did not die, 709 - 152 = 557 people, already had the mutation, or they would have died as well:
This gene mutation, which is found nowhere else in the world, seems to offer high or even complete protection against the development of kuru and has become frequent in this area through natural selection over recent history, in direct response to the epidemic. This is thought be perhaps the strongest example yet of recent natural selection in humans.
The frequency of the hereditary trait increased in the population as a whole because the survivors had the mutation and then passed it on to their descendants while those that perished did not. Notice that a human generation is ~20 years on average, and you need to get from an initial mutation - which is neutral when there is no disease present - to a population of 557 descendants.
I wonder who that 'one" individual is who happened to be around at just the right time to father the entire population of children and pass on the resistance is?
Except (a) it wasn't "at the right time" but well before the epidemic or only the one person would have survived, rather than the evidence of it already being extant in a large number of people (do you have 557 children?) and (b) you didn't read the notes that show only women and young children engaged in the mortuary feast, not men, so the mutation in a man during the epidemic would have had no effect on survival of people.
The other studies mentioned, such as Galapagos finches and Peppered moths, these are all old stories about evolution, but in what way do they test or show the randomness of the mutations and that caused these shifts in populations?
Congratulations, this is a poor debate tactic called "moving the goalposts" -- you originally asked for examples of tests of natural selection: the examples given do that to a "T" as they demonstrate differential survival and the resultant shift in the frequency of hereditary traits in following generations -- and now you are complaining that they are not tests of random mutations.
And also, since in cases like the Galapagos finches, the populations oscillate back to their original forms of shorter beaks, under different environmental conditions, we have to show the same processes happening twice-first a random mutation causes longer beaks to sprout and then those get chosen within the population, and then later wouldn't you know it, another "random" mutation comes along and the exact same slow weeding out process of mates choosing the best beak sizes happens again; and fortuitously the need for a certain beak size remains the single most important consideration for mate selection over the vast spaces of time that natural selection requires. Quite amazing.
Interestingly your opinion, misrepresentation and incredulity are unable affect reality.
(1) the mutation did not occur AFTER the change in ecology, there was existing variation in the population, with a large percentage having large beaks and a small percentage with small beaks. The ones with big beaks can eat the available food easier than the ones with small beaks, with the result that they are healthier and have more time for reproduction.
(2) when the ecology changed the existing individuals with small beaks were favored and the ones with large beaks had trouble surviving: the population shifted to having a large percentage having small beaks and a small percentage with large beaks. The ones with small beaks can eat the available food easier than the ones with big beaks, with the result that they are healthier and have more time for reproduction.
(3) when the ecology returns to what it was in (1) above then once again the existing individuals with big beaks were favored and the ones with small beaks had trouble surviving: the population shifted to having a large percentage having big beaks and a small percentage with small beaks. The ones with big beaks can eat the available food easier than the ones with small beaks, with the result that they are healthier and have more time for reproduction.
No new mutations needed at all.
Similar for the Peppered Moths: both varieties live at the same time, but one is heavily selected against in one ecology, then the other is heavily selected against when the ecology changes, and then this shifts back when the ecology shifts back and the former variety is once again heavily selected against.
This is what I meant by evolution being a response mechanism: some individuals have a better opportunity to survive and reproduce than others, with the response result that they are better represented in the next generation,
but the opportunities change with the changes to the ecology around them (or when they move into new ecologies), with the response result that other individuals are better represented in the next generation, ones that have a better opportunity to survive and reproduce than others.
Or even more amazing still, we have a entire list of traits we are selecting for over many many years of generations, overlapping each other- lung capacity, tail size, genital size, coloration, chirping sound, eyesight, nest building techniques, proper digestive gland sizes, and on and on..and each and every one of these needs is remaining constant long enough after all these random mutations occurred to eventually trickle their way through the selection process. So each time a beak size is being chosen for, all of these other criteria, and about 100,000 = others are also being selected for. It must be a tough choice for a pretty female finch to decide.
I'm sorry, but your impression of how evolution works is extensively incorrect and misinformed. Please read the links provided above - they are used by universities teaching Master's and PhD programs in biological evolution to students learning to become biologist and evolutionist scientists. The information on these two websites is accurate, specific and much more reliable than what you have learned.
Enjoy.
Edited by RAZD, : response
Edited by RAZD, : format

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This message is a reply to:
 Message 17 by Bolder-dash, posted 11-21-2009 7:01 PM Bolder-dash has replied

Replies to this message:
 Message 21 by ICANT, posted 11-22-2009 12:30 AM RAZD has replied
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ICANT
Member
Posts: 6769
From: SSC
Joined: 03-12-2007
Member Rating: 1.5


Message 21 of 302 (536337)
11-22-2009 12:30 AM
Reply to: Message 20 by RAZD
11-21-2009 10:55 PM


Re: Yes ... now the evasion starts?
Hi RAZD,
RAZD writes:
This is what I meant by evolution being a response mechanism: some individuals have a better opportunity to survive and reproduce than others, with the response result that they are better represented in the next generation,
You have 2 populations of finches. One has small beaks the other has large beaks.
During the wet times there are more small beak finches.
During the dry times there are more large beak finches.
That has nothing to do with evolution.
It only has to do with who has the most food. The one that does produces more offspring with a better survival rate. Thus you have more of one than the other.
They not evolving anywhere. They are simply oscillating back and forth with the one with the most food having more offspring.
So what does this test prove.
It proves that the population that gets the most food has the most offspring with the better survival rate.
Nothing more.
God Bless,

"John 5:39 (KJS) Search the scriptures; for in them ye think ye have eternal life: and they are they which testify of me."

This message is a reply to:
 Message 20 by RAZD, posted 11-21-2009 10:55 PM RAZD has replied

Replies to this message:
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Bolder-dash
Member (Idle past 3629 days)
Posts: 983
From: China
Joined: 11-14-2009


(1)
Message 22 of 302 (536341)
11-22-2009 1:32 AM
Reply to: Message 18 by Granny Magda
11-21-2009 8:53 PM


Re: Yes.
Ok, fair enough, I am willing to modify my statement to include what is the modern day accepted form of Darwinian evolution..that is that random mutations are the ingredients for change, and natural selection the filter. If you are in the camp of suggesting that this is not a viable theory, or you believe the modern theory of evolution differs from this, feel free to say so. I hope you can agree to either accept this theory (with caveats of genetic drift, and others if you so choose) or reject it to keep the discussion on topic.

This message is a reply to:
 Message 18 by Granny Magda, posted 11-21-2009 8:53 PM Granny Magda has not replied

Bolder-dash
Member (Idle past 3629 days)
Posts: 983
From: China
Joined: 11-14-2009


Message 23 of 302 (536343)
11-22-2009 2:08 AM
Reply to: Message 20 by RAZD
11-21-2009 10:55 PM


Re: Yes ... now the evasion starts?
If you wish to win an argument based on sheer volume of typing, I will simply defer now. I won't however defer based on your tired and worn out theme of "well you just don't know biology, so you are wrong" argument (I even suggested when I first proposed this topic that this type of defense be excluded, because its simply not saying a dam thing.., but the admin required me to remove that part of my suggestion-although I knew it wouldn't take long for someone to drag it out).
I think you answers are basically fit for a 7 year old. I know exactly what the theory suggests, every bit as much as you do.
First, I could provide the exact article for this quote, but it is beside the point. The question is not what the editor meant, the question is have random mutations and natural selection been rigorously tested. Why obscure this point.
quote:
changes in "body structure and living systems" are actually the accumulation of many smaller changes, taking place over multiple generations, so no, you are not going to see this kind of change in one study.
I think this provides your answer with much more brevity. No this can't be tested.
Furthermore, I take exception with your claim that by asking for evidence of natural selection creating evolutionary change, it is moving the goal posts to require that this takes random mutations into account. If you don't feel that random mutations must be evidenced in the study of natural selction-then what the heck are we saying exactly? That some animals with bad gentics die, and some with good gentics live longer? Ok, I accept that. So what does that tell us about anything? You mean to suggest that you wanted to just take the literal meaning of natural, and the literal meaning of selection and show that things are natural, and thing are selected? Yes, I agree, we are not made of unnatural things like teflon, and yes, people select their partners for the most part. Not very breathtaking science in this day and age.
I appreciate your participation, but honestly I wasn't coming here to get a 6th grade lecture from you-I come here seeking depth and insight.
If you wish to argue the finer points of evolution, you can't just gloss over all the logical assumptions one must make to have the theory make any sense at all. If people in one region of the world suddenly develop a resistance to a rare disease, a resistance people in other parts of the world never seem to spontaneously develop, we must think long and hard about how and why that happened. Was it really just that one guy happened to get this fortunate mutation. Do people in other parts of the world occassional get a similar random mutation? Do people in other parts of the world occassionally get born with resistance to bubonic plague, to Lou Gehrig's disease, to the anthrax virus, to arsenic? How often does this happen randomly?
These are just some of the questions that have to be asked and tested before we can say that this "theory" has been vigorously verified.

This message is a reply to:
 Message 20 by RAZD, posted 11-21-2009 10:55 PM RAZD has replied

Replies to this message:
 Message 30 by RAZD, posted 11-22-2009 11:38 AM Bolder-dash has replied

Bolder-dash
Member (Idle past 3629 days)
Posts: 983
From: China
Joined: 11-14-2009


Message 24 of 302 (536344)
11-22-2009 2:22 AM
Reply to: Message 19 by CosmicChimp
11-21-2009 10:22 PM


Hello cosmic chimp,
The author of the study himself declared that this resistance happened in a matter of a few decades.
Now you might expect that this protective polymorphism would be disproportionately represented in a population which has been exposed to this disease-but the fact remains, we still have to account for how it got there in the first place in a logical fashion. ONE individual must have gotten this mutation first, yes?
How often do you suppose this exact mutation happens in the entire population of the world? Every 10,000 individuals gets this? If we tested 10,000 Americans, would we find at least one with this mutation? 100,000? How about a random mutation for resistance to dioxin? How many individuals presently living in the world have a resistance to dioxin? One in a million? One in a billion? Does anyone have this? Rabies? How many people are born every year with a random mutation for resistance to rabies?
Don't we need to know this, to know just how fortunate were the odds that one of the members of this small tribe just so happened to be born with a random resistance to kuru disease? When did it happen, 100 years ago? 1000 years ago?

This message is a reply to:
 Message 19 by CosmicChimp, posted 11-21-2009 10:22 PM CosmicChimp has replied

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 Message 25 by Wounded King, posted 11-22-2009 6:21 AM Bolder-dash has replied
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Wounded King
Member
Posts: 4149
From: Cincinnati, Ohio, USA
Joined: 04-09-2003


(1)
Message 25 of 302 (536352)
11-22-2009 6:21 AM
Reply to: Message 24 by Bolder-dash
11-22-2009 2:22 AM


How often do you suppose this exact mutation happens in the entire population of the world?
You are assuming that this exact mutation has to arise for there to be a protective effect. In fact there may be a number of other mutations with similar functional effects. But once such a trait has appeared in a population where there is a strong selective pressure to promote its spread then other protective mutations would be redundant. We don't know this is the only mutation to have this effect, only that it was the first to spread through the affected population.
How many individuals presently living in the world have a resistance to dioxin?
Dear Mr Bolder-dash,
The ethics committee has decided to decline your request for approval to subject living human beings to dioxin poisoning in order to test for heritable resistance traits.
Yours, The ethics committee.
The problem with your suggestion is that a lot of these are very sporadic environmental factors. You are unlikely to find a population which is consistently being bitten by rabid dogs, or hopefully exposed to dangerous levels of dioxin. In almost all the cases of identified protective mutations in humans they are for factors which are endemic to the population in which they are identified.
There may well be mutations which could confer some degree of resistance to dioxin arising, but there is going to be very little selective pressure to maintain such a trait unless the population is consistently being exposed to dangerous levels of dioxin, but low enough to allow the maintenance of a breeding population.
We just can't know what these mutations are until they have somehow been identified, there are just too many possible mutations and we know too little to be able to predict the effect of most of them.
Don't we need to know this, to know just how fortunate were the odds that one of the members of this small tribe just so happened to be born with a random resistance to kuru disease?
I think the number of factors needed to make accurate probability assessments too great for it to really be tenable, one of those factors would be all of the other possible mutations conferring a similar degree of protection. If we could do it it would certainly be interesting but I'm not sure it would really tell us anything important about natural selection or evolution in general.
TTFN,
WK

This message is a reply to:
 Message 24 by Bolder-dash, posted 11-22-2009 2:22 AM Bolder-dash has replied

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 Message 31 by Bolder-dash, posted 11-22-2009 12:59 PM Wounded King has replied

CosmicChimp
Member
Posts: 311
From: Muenchen Bayern Deutschland
Joined: 06-15-2007


Message 26 of 302 (536367)
11-22-2009 8:39 AM
Reply to: Message 21 by ICANT
11-22-2009 12:30 AM


Special pleading, begging even.
It seems to me that you have stated that all of the properties of evolution are present; but then go on to claim that what is observed is not evolution. Other than your special pleading claim, that it is not evolution, can you somehow show that what happened is not evolution? Because it is evolution. It really and truly is evolution, by definition. If you want any more than my special pleading review RAZD's post it's all in there.
Edited by CosmicChimp, : new subheading

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lyx2no
Member (Idle past 4715 days)
Posts: 1277
From: A vast, undifferentiated plane.
Joined: 02-28-2008


(1)
Message 27 of 302 (536369)
11-22-2009 9:30 AM
Reply to: Message 17 by Bolder-dash
11-21-2009 7:01 PM


Not Now
It is kind of funny that one would cite a population of people developing a resistance to disease in a few decades as evidence that Darwin's theorized process of slow gradual change, based on random mutations caused these resistances. This was a random mutation that just so happened to crop up exactly in a population that was experiencing the disease, in exactly the right time(down to the decade) that the population was being exposed to the pressure? That is some serious good fortune. I wonder who that 'one" individual is who happened to be around at just the right time to father the entire population of children and pass on the resistance is? I guess the entire population can be traced by to one very prolific and possibly still alive reproducer.
This paragraph shows a common misconception about evolution: The timing of the mutation is concurrent with the timing of its value. It is not. The mutation may have happened a thousand generations prior.
Say a simple mutation makes an apparently unimportant change in an apparently unimportant protein. This protein is passed down in happenstance fashion for twenty thousand years and now 2% of the tribe has it. Then along comes a virus that just happens to use that particular protein as its gateway into the cell. Our virus also finds that the modified protein "tastes" like crap and shows a reluctance to "eating" it; a reluctance that gives the carriers immune system time to out pace our virus. A dozen generations down the road, through the attrition of non-carriers, our modified protein is now found in 20% of the population. That may mean that there are now enough people that are resistant to the virus that an epidemic can not be supported. The virus becomes rare. Ta_da!
Straw men understandings of evolutionary mechanism can lead to erroneous arguments. That a mutation happens at just the right time is very unlikely and would certainly be a problem. luckily it doesn't have to. Some folks might want to give scientist a bit more credit for having possibly resolved some of these simple misunderstandings decades ago. long before the new guy reapplied the misunderstand.

It's not the man that knows the most that has the most to say.
Anon

This message is a reply to:
 Message 17 by Bolder-dash, posted 11-21-2009 7:01 PM Bolder-dash has replied

Replies to this message:
 Message 37 by Bolder-dash, posted 11-22-2009 9:39 PM lyx2no has not replied

RAZD
Member (Idle past 1404 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


(1)
Message 28 of 302 (536370)
11-22-2009 9:43 AM
Reply to: Message 21 by ICANT
11-22-2009 12:30 AM


The evolutionary two-step
Hi ICANT, hope you are well.
You have 2 populations of finches. One has small beaks the other has large beaks.
No, you have one population of breeding individuals with variation in the size of the beaks, from small to large.
During the wet times there are more small beak finches.
During the dry times there are more large beak finches.
During climatic changes to the ecological environment that span several years (ie not just seasonal changes involved) the frequency distribution of beak sizes changes in the population, with small beaks being favored in the wetter ecology and large beaks being favored in the dryer ecology.
It only has to do with who has the most food. The one that does produces more offspring with a better survival rate. Thus you have more of one than the other.
Which is how natural selection works as a part of evolution.
That has nothing to do with evolution.
Incorrect, it is fundamental to evolution. Without selection there would be no diversity of life.
They not evolving anywhere. They are simply oscillating back and forth with the one with the most food having more offspring.
Correct, evolution does not have a direction, and thus oscillation back and forth is just as much evolution as any gradual trend in one direction (larger beaks over time) or the other (smaller beaks over time).
Evolution is a response mechanism, and thus when climatic changes oscillate back and forth over long time periods, then selection will take place such that the population oscillates to match the changes in the ecology (or perish).
So what does this test prove.
That natural selection does occur in the field, and it can be documented as the response to specific ecological changes. In wet ecologies selection occurs in one direction, in dry ecologies selection occurs in the other direction.
These are just short term changes, the changes in the frequency of hereditary traits within a breeding population that occur from generation to generation based on (a) the ecology where the species lives, and (2) the available variations within the species population.
For longer term changes you need to consider that evolution is a 2-step dance, an endless do-loop program:
Step 1: mutations: Mutations cause variations within the breeding population.
Step 2: selection: Selection occurs when there is a benefit to having a particular variation or a cost to having a particular variation.
Go back to Step 1.
Mutations occur randomly during pre-reproduction in the reproductive cells of an organism, during the reproductive process when DNA is copied with some changes due to copy errors, and during the organism development process as the organism is growing by cell division. The ones that don't result in death of the individual before reproduction can get passed on to the next generation. This includes beneficial mutations, neutral mutations, and mildly deleterious mutations. By the time an individual organism reaches reproductive age the mutation process has stopped for that individual: they are either fit to survive and breed in their ecology or they are not.
Selection occurs on the existing variations and acts on the individuals within a breeding population. Those that survive long enough to breed then passing their hereditary traits on to their descendants in the next generation of the breeding population. Those that are better able to breed more often (healthier, well fed, longer lived, attractive to mates, etc) will produce more offspring, and thus their hereditary traits will have a higher frequency distribution in the next generation then those less able to breed often.
Evolution occurs on the breeding population as a whole, not on the individuals, through population dynamics. As the frequency distribution of hereditary traits within a population changes so too do the breeding opportunities change, with the result that more successful traits spread through the population and less successful traits become less common.
They are simply oscillating back and forth with the one with the most food having more offspring.
Meanwhile, selection neutral hereditary changes in the population - changes that do not affect relative survival in wet/dry selection - can still occur in the population such that there is a difference between the initial wet ecology population and the repeated wet ecology population, changes that either occurred due to secondary selection for the dry ecology, or changes that are of a different trait unrelated to wet or dry ecologies.
Example: tail length could be selected for longer tails by sexual selection, and this process would continue through the dry period and the return to the wet period, but the population in the second wet period would all have longer tails than the population in the first wet period.
Enjoy.

we are limited in our ability to understand
by our ability to understand
Rebel American Zen Deist
... to learn ... to think ... to live ... to laugh ...
to share.


• • • Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click) • • •

This message is a reply to:
 Message 21 by ICANT, posted 11-22-2009 12:30 AM ICANT has replied

Replies to this message:
 Message 50 by ICANT, posted 11-23-2009 4:18 PM RAZD has replied

lyx2no
Member (Idle past 4715 days)
Posts: 1277
From: A vast, undifferentiated plane.
Joined: 02-28-2008


(1)
Message 29 of 302 (536371)
11-22-2009 9:52 AM
Reply to: Message 21 by ICANT
11-22-2009 12:30 AM


Two Populations
You have 2 populations of finches. One has small beaks the other has large beaks.
Wrong. You have one population of finches with a bell curve range of beak sizes. With short term fluctuations in the the environment the center of the curve moves back and forth. However, if the environmental change is long term the displacement of the center of the curve may become permanent if all of the gene carries at the distal extreme are eliminated.
If this environmental change did not occur over the entire range of the finch population then the curve may become bi-modal. If the reproductive range of individual finches is much smaller than the range of the population then the bi-modality can increase until there are two separate population that do not interbreed. There is a name for this but I can't remember what it is off the top of my head. Help me out ICANT.
AbE: Right in the neck.
Edited by lyx2no, : Ninjad.
Edited by lyx2no, : "will" to "may".

It's not the man that knows the most that has the most to say.
Anon

This message is a reply to:
 Message 21 by ICANT, posted 11-22-2009 12:30 AM ICANT has not replied

RAZD
Member (Idle past 1404 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


(1)
Message 30 of 302 (536378)
11-22-2009 11:38 AM
Reply to: Message 23 by Bolder-dash
11-22-2009 2:08 AM


Re: Yes ... now the finer points?
Hi Bolder-dash,
If you wish to win an argument based on sheer volume of typing, I will simply defer now.
When you ask a question or make a comment that needs a long explanation to cover all the points you have raised, then you can expect a long response. Typically such questions and comments are due to being wrong or misinformed about certain aspects of the topic, so those erroneous bits need to be corrected: the more erroneous bits in your questions and comments, the longer a full response will be. The alternative is just to say that you are ignorant of the topic, which I agree is no answer.
I won't however defer based on your tired and worn out theme of "well you just don't know biology, so you are wrong" argument (I even suggested when I first proposed this topic that this type of defense be excluded, because its simply not saying a dam thing.., but the admin required me to remove that part of my suggestion-although I knew it wouldn't take long for someone to drag it out).
Which is why I provided sources for you to look at and determine for yourself if you are right or wrong. This is also why I explained at length why your information was false.
Either don't complain about the length or don't complain about being labeled as uninformed.
For the record, these are comments of yours that are either wrong or confused (taken from one paragraph in Message 17):
  1. what they all demonstrate is that a change was "needed" in a population and the change occurred.
  2. random mutations slowly drifted through the populations along with every other kind of random mutation,
and these are comments of yours that are either wrong or confused (taken from another paragraph in Message 17):
  1. funny that one would cite a population of people developing a resistance to disease in a few decades as evidence that Darwin's theorized process of slow gradual change,
  2. a random mutation that just so happened to crop up exactly in a population that was experiencing the disease, in exactly the right time(down to the decade)
  3. That is some serious good fortune.
  4. I wonder who that 'one" individual is who happened to be around at just the right time
  5. to father the entire population of children and pass on the resistance
  6. I guess the entire population can be traced by to one very prolific and possibly still alive reproducer.
  7. That is one very inbred society
  8. The entire population was fathered by one man (or woman), who might even still be alive!
That's 10 erroneous comments in two paragraphs of a relatively short post. The astute reader will note that the second list is just about every comment you made in that paragraph.
I know exactly what the theory suggests, every bit as much as you do.
Obviously not, as you would not make such a plethora of false and confused statements if you did understand the theory of natural selection and the process of evolution, as it is used in biological sciences by biological scientists and as documented in the links I provided.
What you have is an opinion based on erroneous information, either through misunderstanding of the science, or through your being given false information instead of actual information about evolution.
I think you answers are basically fit for a 7 year old.
I appreciate your participation, but honestly I wasn't coming here to get a 6th grade lecture from you-I come here seeking depth and insight.
Amusingly, this means that you should be able to understand it then, yes? You should also be able to comprehend when you are wrong, and have the cognitive skills to update your thinking with proper information (ie - go to links to university programs on evolution: you should be able to understand them as well, yes?).
First, I could provide the exact article for this quote, but it is beside the point.
Please do - it is very much the point, as you are using it to claim that some authority made the comment, and that authority has not been established. Please also provide the link where you found the article if that is different from the actual article.
Message 24: The author of the study himself declared that this resistance happened in a matter of a few decades.
Please quote where he says that. Here is the link again:
Page not found — UKRI
and the pertinent quote:
quote:
Lead author Professor John Collinge, Director of the MRC Prion Unit said:
It’s absolutely fascinating to see Darwinian principles at work here. This community of people has developed their own biologically unique response to a truly terrible epidemic. The fact that this genetic evolution has happened in a matter of decades is remarkable. Kuru comes from the same disease family as CJD so the discovery of this powerful resistance factor opens up new areas for research taking us closer to understanding, treating and hopefully preventing a range of prion diseases.
The study A Novel Protective Prion Protein Variant that Colocalizes with Kuru Exposure, which began in 1996, will be published in the New England Journal of Medicine on 19 November 2009.
Where does it state when the mutation occurred? The selection occurs over a period of decades, because the selection is a simple pass\fail survival test, but we don't know when the mutation occurred.
The fact that there were 577 descendants of the "father" (or mother) with the original mutation speaks to it having occurred many many generations before the epidemic. If we assume three offspring per generation reach the age of reproduction to pass on the mutation, and an average generation time of 20 years, this works out to 116 years minimum (assuming the gene was always passed on to children, and that no intermarriage of descendants occurred even though 6 generations is enough to allow intermarriage in most cultures, especially with tribal customs). If we assume that the mutation was only passed to half of the children this grows to 314 years and 16 generations minimum before the epidemic. The actual time is likely even longer.
Note that we do not know when Kuru first developed.
Kuru (disease) - Wikipedia [quote]Kuru was first noted in the Fore tribe of the Eastern Highlands Province of Papua New Guinea as Australian administrators explored the area in 1957—1959. It was in the late 1950s that the full extent of the disease was realized, after it had reached large infection rates in the South Fore of the Okapa Subdistrict, though the agent was unknown.[6][/qs]
So it could have existed before then, and people with the mutation could have been descendants of survivors of previous exposure to the disease.
quote:
changes in "body structure and living systems" are actually the accumulation of many smaller changes, taking place over multiple generations, so no, you are not going to see this kind of change in one study.
I think this provides your answer with much more brevity. No this can't be tested.
Nor is this natural selection, rather it is the whole process of evolution - the change in the distribution of hereditary traits in breeding populations from generation to generation - taken over many generations and involving many different hereditary traits being combined.
Furthermore, I take exception with your claim that by asking for evidence of natural selection creating evolutionary change, it is moving the goal posts to require that this takes random mutations into account.
You asked if natural selection was really tested and verified (see topic title), not whether macroevolution - the long term result of evolutionary change in diverging species over many generations - had been tested and verified.
If you don't feel that random mutations must be evidenced in the study of natural selction-then what the heck are we saying exactly?
That mutation\variation and natural selection are two different processes within evolution. A rather simple concept.
That some animals with bad gentics die, and some with good gentics live longer? Ok, I accept that. So what does that tell us about anything?
That natural selection occurs, and that it has been tested and verified.
You mean to suggest that you wanted to just take the literal meaning of natural, and the literal meaning of selection and show that things are natural, and thing are selected?
Curiously, that is exactly what Darwin meant when he formulated the theory of Natural Selection
Darwin Online
On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. [1st edition]
NOTE: This is the first edition of Darwin's most famous work. It was published 24 November 1859.
Another good link to actual information about evolution in general and Darwin's theory in particular, eh?
If people in one region of the world suddenly develop a resistance to a rare disease, a resistance people in other parts of the world never seem to spontaneously develop, we must think long and hard about how and why that happened. Was it really just that one guy happened to get this fortunate mutation. Do people in other parts of the world occassional get a similar random mutation? Do people in other parts of the world occassionally get born with resistance to bubonic plague, to Lou Gehrig's disease, to the anthrax virus, to arsenic? How often does this happen randomly?
Often enough, and sufficiently prior to selection pressure (NOT suddenly) for the surviving species to survive, OR they are not endemic enough to wipe out a surviving species (other populations protected by being geologically separated), OR the species go extinct.
Fascinatingly, extinction is a frequent occurrence in the natural history of life on earth.
If you wish to argue the finer points of evolution, you can't just gloss over all the logical assumptions one must make to have the theory make any sense at all.
We have now established that natural selection is an observed, tested and verified process within evolution. No assumptions required for that.
Next, if you wish, we can discuss whether mutations are an observed, tested and verified process within evolution. Do you want to start a thread on that (so that the two processes can be discussed separately) or do you want to continue on this thread, now that your original question - Has natural selection really been tested and verified? - has been answered, and accepted as true?
Enjoy.

we are limited in our ability to understand
by our ability to understand
Rebel American Zen Deist
... to learn ... to think ... to live ... to laugh ...
to share.


• • • Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click) • • •

This message is a reply to:
 Message 23 by Bolder-dash, posted 11-22-2009 2:08 AM Bolder-dash has replied

Replies to this message:
 Message 40 by Bolder-dash, posted 11-22-2009 10:15 PM RAZD has replied

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