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Old 30th January 2015, 09:33 AM   #41
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Originally Posted by Darwin123 View Post
Lamarkian-evolution has basically been disproved. This is the simplistic way to answer the OP. However, I am talking about the grey areas in biology. These grey areas are still being researched.
Thanks Darwin123, you explain that well - even for my very rusty knowledge. Certainly the details of evolution's nitty-gritty are far more complex than is generally know to types like me who have only read a few popular books like The Selfish Gene.
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Old 30th January 2015, 09:53 AM   #42
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Originally Posted by Reality Check View Post
Lamarckism would be dark skinned people choosing to paint themselves white and actually becoming pale skinned !


On a related note, it seems that it's being recognised that adaptation may play a larger role in the evolutionary story than thought, in that populations forced into an environment for which they are not well adapted, may show considerable developmental adaptation; so that within two or three generations, there are considerable and consistent phenotypic differences compared to the original population, without significant genetic changes.

In severe environments, the argument goes, these developmental adaptations should increase the likely population survival time, giving more time for advantageous traits to be fixed genetically by selection. But it seems to me that the better the developmental adaptability, the less impact natural selection will have on those traits, so when the environment is in flux over relatively short evolutionary timescales, the selective advantage will favour adaptability over specific phenotypic traits...?

Anyhoo, if it is likely that two genetically identical populations may have significantly different musculoskeletal development according to their respective environments, could this have implications for fossil-based taxonomy?
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Old 30th January 2015, 10:19 AM   #43
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Originally Posted by Lukraak_Sisser View Post
Usually the cells are self competent (ie they can take up whole DNA and integrate it into their genome). Other organisms die in the area and their DNA is scattered. If the DNA contains something like antibiotic resistance it can be transferred that way.
I'm not saying its pure lamarckism, but its not a gene from the same organism mutating into something new either. There is a reason the current theory of evolution is more complex than originally thought.
I get all that, I just don't see the invocation of Lamarck as being appropriate.
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Old 30th January 2015, 12:59 PM   #44
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Originally Posted by dlorde View Post


Anyhoo, if it is likely that two genetically identical populations may have significantly different musculoskeletal development according to their respective environments, could this have implications for fossil-based taxonomy?
This is not inheritance of acquired characteristics because it doesn't occur over generations. This is called plasticity.


Sun tans would be an example of plasticity. Any person other than a complete albino will respond to sunlight by having a darker skin. This is as true for Negroes as it is for Caucasians. The skin responds to the ultraviolet and light by secreting more melanin. The tan has little to do with primary changes in the DNA structure.

The condition of having more melanin because of extra sunshine is referred to as a tan. The tan involves changes in the RNA and protein of the skin cell. The ability to develop a tan is a type of plasticity since the development isn't associated with the primary structure of DNA.

Tans are not hereditary because the DNA structure in the gametes are not affected by the melanin on the skin. A family of pale skinned people who decide to get tans will have pale skinned offspring.

Sunlight can affect the DNA structure in the skin cells. The effect of sunlight on the DNA of individual skin cells is random. For instance, sunlight may destroy the DNA. The skin cell will then die. Sunlight can cause skin cancer. Before modern medicine, acquisition of skin cancer generally killed the organism. Sunlight can affect the DNA of a skin cell by making the cell secrete less melanin. Sunlight can also affect DNA of a skin cell by making the cell secrete more melanin.

People are born with certain complexions do to the genes. The specific structure of DNA is associated with maybe four pairs of genes with about two possible alleles each. Each combination of alleles is associated with a range of potential complexions. This combination is characterizes the populations of people.

Sunshine can change the primary DNA structure in a skin cell. However, this change isn't inherited because it doesn't affect the gametes. In order for a mutation in a skin cell to affect the gametes, there would have to be a high quality communication channel between skin and gonads.

A pale person can roast himself for hours in the sun. His skin could turn dark black due to melanin. A skin cell could even mutate, forming a different DNA sequence at random. There is no way that the gametes in the gonads can change due to the sun. So that person will have children whose genomes are a mixture of genes from that person and the mate.

Skin cancer is caused by a random mutation in the skin. It doesn't directly pass down to the gamete cells. However, skin cancer does contribute to evolution. A person who got skin cancer general in the good old days would die with few exceptions. So they had less children. However, people with less melanin had a better chance of surviving. So in sunny climates, people with the right combination of genes had a better chance of surviving.

There is a trade off. If a person has lots of melanin, then he can't make much vitamin D using sunlight. So people inside northern Europe far from the sea may have suffered rickets from the lack of vitamin D. So the inland Europeans evolved had pale skin. However, people who lived close to the sea can get lots of vitamin from fish. So maybe coast Asians and aboriginal Americans thousands of years ago didn't need sunlight for their vitamin D. However, their was enough sunlight to create a problem with skin cancer. So the balance of risk went against pale skinned people near shore.

Eskimos (e.g., Inuits) get plenty sunshine during the summer. During that time, skin cancer is a risk. They get very little sunshine during the winter. Not only is the sun low in the sky, but their winter cloths are very thick. However, much of their traditional diet at this time comes from cold water fish. Cold water fish have lots of vitamin D. So Eskimos don't need sunshine at any time. Better to be dark skinned so as to avoid skin cancer during the summer. So natural selection doesn't favor pale Eskimos.

I think the skin problem was more or less resolved when those four pairs of genes were discovered. There has been no mechanism discovered by which the condition of the skin affects the structure of those genes in a gamete.

I don't think the fossil record tells you which changes occurred due to plasticity and which due to genetics. This is why there was still a question of Lamark versus Darwin for a long time. For the most part, the question was resolved in favor of Darwin.

Pay attention to the epigenetic research. Someone may find a Lamarkian modification of skin color, yet. No one has found any so far.
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Old 30th January 2015, 01:37 PM   #45
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Nice.

Thanks for taking the time to lay that out.
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Old 30th January 2015, 02:10 PM   #46
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Originally Posted by Maartenn100 View Post
That isn't an answer Lamarck said that adaption occurred through direct changes in the physical organism. Not genes.

Acquired, as it I get a sun tan, so my baby has a sun tan, not that I have genes for a nice sun tan and pass them on.

You didn't read before you posted "He believed that the long neck of the giraffe resulted from the ancestors of giraffes stretching their necks longer and longer while trying to reach the highest branches of the trees"

No genes there,
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Old 30th January 2015, 02:17 PM   #47
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Originally Posted by Fast Eddie B View Post
That is the problem.

Dawkins is in my opinion the best popularizer of Evolutionary Theory.

Try "The Blind Watchmaker" or "The Selfish Gene" or even "The Ancestor's Tale".

Until you do, you're just either thrashing or trolling.
Not sure about the other two but I have read "Ancestor's Tale". It pretty dense, or at least complex, reading. Takes a bit of thought to grasp all the concepts put forth in the begging of the book so as to be able to apply them as he refers to them later.
Liked it very much.
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Old 30th January 2015, 03:02 PM   #48
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Originally Posted by jaydeehess View Post
Not sure about the other two but I have read "Ancestor's Tale". It pretty dense, or at least complex, reading. Takes a bit of thought to grasp all the concepts put forth in the begging of the book so as to be able to apply them as he refers to them later.
Liked it very much.
That's why I said even "The Ancestor's Tale".

I think "The Blind Watchmaker" is probably Dawkins' best as a first read.

At least it was for me.
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Old 30th January 2015, 04:54 PM   #49
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Originally Posted by Darwin123 View Post
This is not inheritance of acquired characteristics because it doesn't occur over generations. This is called plasticity.
Yes, that's what I was talking about. That's why I said "without significant genetic changes". Sorry if that wasn't clear.

Quote:
I don't think the fossil record tells you which changes occurred due to plasticity and which due to genetics. This is why there was still a question of Lamark versus Darwin for a long time. For the most part, the question was resolved in favor of Darwin.
Presumably one can sometimes get hints from the environmental context.
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Old 30th January 2015, 06:06 PM   #50
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Originally Posted by Dancing David View Post
That isn't an answer Lamarck said that adaption occurred through direct changes in the physical organism. Not genes.

Acquired, as it I get a sun tan, so my baby has a sun tan, not that I have genes for a nice sun tan and pass them on.

You didn't read before you posted "He believed that the long neck of the giraffe resulted from the ancestors of giraffes stretching their necks longer and longer while trying to reach the highest branches of the trees"

No genes there,
No genes in any of Darwin's books, either. The word 'gene' wasn't applied to anything in heredity until almost a hundred years after the publication of 'Origin of the Species'. Hence, the concept of 'gene' can't be used to distinguish between Darwin's theory and Lamark's theory.

Darwin used the word 'variation' to describe all inheritable differences between organisms. He used the phrase 'spontaneous variation' that occurred unpredictably and which would be inherited in consequent generations. He use the word 'chance' instead of 'random'.

The meaning of his words in the context of his books is clear. Even though the words now used are different, one can still claim reasonably that Darwin has been proved right. I suppose Darwin's 'variation' would today include changes due to both genetic recombination and mutation. I suppose 'spontaneous variation' is what we would call mutation. Even his 'pangene' concept may have something to do with RNA. However, precise correlation between todays jargon and Darwin's jargon is not possible.

It is important to realize that the theory of biological evolution has advanced a lot since Darwin's day. Words have been coined to facilitate detailed discussion. However, Darwin did not know a single thing about DNA or RNA. So any concept implicitly connected with the chemical nature of DNA or RNA can't be associated with either Darwin, Lamark or Mendel.
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Old 31st January 2015, 04:02 AM   #51
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Originally Posted by Darwin123 in #38 View Post
Lamarkian-evolution has basically been disproved.

Lamarckism is only "disproved" by the untenable premise that genes contain the relevant information of an organism.

Darwinism however is disproved by empirical facts, the results of so-called adverse selection experiments:
"Tryon has bred rats selectively according to their ability on the California automatic maze, and, in a very carefully controlled experiment, has shown clearly that the offspring of 'bright' parents contain more 'brights' than 'dulls', and that the offspring of 'dulls' more 'dulls' than 'brights'. The interesting point here in connection with Lamarckian inheritance, however, is that both strains, 'dulls' as well as 'brights', became progressively better at learning this maze." (Nature, Feb. 4, 1939, Vol. 143, p.190)
And how do you explain William McDougall's experiment on the inheritance of acquired habits in rats?

Cheers, Wolfgang
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Old 31st January 2015, 05:55 AM   #52
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Originally Posted by wogoga View Post
Darwinism however is disproved by empirical facts, the results of so-called adverse selection experiments:
I suspect you're going to have to do better than that.
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Old 31st January 2015, 07:15 AM   #53
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Originally Posted by wogoga View Post
Lamarckism is only "disproved" by the untenable premise that genes contain the relevant information of an organism.

Darwinism however is disproved by empirical facts, the results of so-called adverse selection experiments:
"Tryon has bred rats selectively according to their ability on the California automatic maze, and, in a very carefully controlled experiment, has shown clearly that the offspring of 'bright' parents contain more 'brights' than 'dulls', and that the offspring of 'dulls' more 'dulls' than 'brights'. The interesting point here in connection with Lamarckian inheritance, however, is that both strains, 'dulls' as well as 'brights', became progressively better at learning this maze." (Nature, Feb. 4, 1939, Vol. 143, p.190)
And how do you explain William McDougall's experiment on the inheritance of acquired habits in rats?

Cheers, Wolfgang
Apart from the fact that all empirical data in all fields that use the theory of evolution show that the vast majority of evolution proceeds in a pretty much darwinian way, yes I'm sure that it's been disproved.
But please, do explain using any other method WHY we can use yeast genetics to make correct and verifiable predictions in the human genome.

That fact that there are a few sidelines that darwin did not predict or know about that make evolution more complex does not mean that his theory has been disproven.
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Old 31st January 2015, 11:08 AM   #54
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Originally Posted by Reality Check View Post
And where is the actual question about Lamarckism, Maartenn100?
You are saying that skin colors are an adaption to climate - that is "Darwinism" (should really be the modern evolutionary synthesis)
Also "natural selection or because of genetic adaptation" is too vague. Evolution is both natural selection and genetic adaptation.

Lamarckism would be dark skinned people choosing to paint themselves white and actually becoming pale skinned !
I always think of it as Just So stories - as an aside, I don't mind Kipling too much compared to other writers of his era.
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Old 31st January 2015, 08:35 PM   #55
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Originally Posted by wogoga View Post
Lamarckism is only "disproved" by the untenable premise that genes contain the relevant information of an organism.

Darwinism however is disproved by empirical facts, the results of so-called adverse selection experiments:
"Tryon has bred rats selectively according to their ability on the California automatic maze, and, in a very carefully controlled experiment, has shown clearly that the offspring of 'bright' parents contain more 'brights' than 'dulls', and that the offspring of 'dulls' more 'dulls' than 'brights'. The interesting point here in connection with Lamarckian inheritance, however, is that both strains, 'dulls' as well as 'brights', became progressively better at learning this maze." (Nature, Feb. 4, 1939, Vol. 143, p.190)
And how do you explain William McDougall's experiment on the inheritance of acquired habits in rats?

Cheers, Wolfgang
Wogoga - If you're going to quote from an article, the least you could do is quote some of the really interesting parts:

"The facility in learning the task is transmitted not through genes but through reincarnation. For an improvement in learning, it is necessary that the souls of the offspring are the souls of the rats which have done the experiment earlier."
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Old 31st January 2015, 08:45 PM   #56
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"So the only reasonable explanation of McDougall's experiment seems to be the psychon thesis. All facts are consistent with this reincarnation theory."

Wow!
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Old 31st January 2015, 09:21 PM   #57
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Originally Posted by Maartenn100 View Post
For example: black and white people.
Why are there a lot of black people in Africa and white people in Europe or North-America?
Could the 'mutation' black not survive in Western countries. Did the mutation white not survive in African countries?
Or is it because of genetic adaptation to the climate (sun).
More sun: skin becomes black.
This is your answer. Please read it carefully and follow it's points. That way I do not need to type it all out myself only to realize a few posts later that functional reading of it/attention to it had not been paid.: http://discovermagazine.com/2001/feb/featbiology
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Old 1st February 2015, 04:53 AM   #58
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Originally Posted by McHrozni View Post

What many people don't realize is that the two systems are not mutually exclusive and can easily coexist. We know Darwins' system of natural selection works in nature and is hard at work there, but we only know of one species that has the capacity to utilize Lamarcks' system - humans, obviously.

McHrozni
I believe that Jewish men have been conducting an experiment to test whether Lamarkian evolution is true, for a few thousand years now.
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Old 1st February 2015, 07:07 AM   #59
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Originally Posted by Mashuna View Post
I believe that Jewish men have been conducting an experiment to test whether Lamarkian evolution is true, for a few thousand years now.
Jewish male babies will be born with a predilection to beg for sex?

Last edited by Fast Eddie B; 1st February 2015 at 07:09 AM.
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Old 1st February 2015, 10:09 AM   #60
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Originally Posted by Mashuna View Post
I believe that Jewish men have been conducting an experiment to test whether Lamarkian evolution is true, for a few thousand years now.
And Moslems. It is a shame that the foreskin hasn't disappeared over all this time, though.
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Old 1st February 2015, 11:00 AM   #61
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Originally Posted by Maartenn100 View Post
For example: black and white people.
Why are there a lot of black people in Africa and white people in Europe or North-America?
Could the 'mutation' black not survive in Western countries. Did the mutation white not survive in African countries?
Or is it because of genetic adaptation to the climate (sun).
More sun: skin becomes black.
So, if a white person is born in Africa and lives there all their life, they become black?
And if a black person is born in Scandinavia and livas ther all their live, they become white?

No? - Well, so much for adaptation.

Note: There is no such thing as "genetic adaptation"; your genes don't change, but those of your offspring who have the most suitable genes may have a better chance of susrvival.

There IS, however, recent research that gives Lamarck a small pont. It seems that some genes can be switched on or off, according to outside stimuli. Thus, for example, children who grow up in a situation where food is always scarce, will tend to be smaller, even as adults, than if there was plenty of food. This is called a phenotype adaptation. If several generations exist under hunger conditions, a smaller genotype will be selected for (the smaller body requires less food).

Hans
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Old 1st February 2015, 12:29 PM   #62
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Originally Posted by MRC_Hans View Post
So, if a white person is born in Africa and lives there all their life, they become black?
And if a black person is born in Scandinavia and livas ther all their live, they become white?
Excellent phrasing! I'm a whitey who's grown-up from a dot in Africa and I'm still pallid. I have the empty bottles of sunblock lotion to prove it!

Quote:
Note: There is no such thing as "genetic adaptation"; your genes don't change, but those of your offspring who have the most suitable genes may have a better chance of susrvival.
Dug your post, loved the typo. It looks like suss + rival, which is a gene's eye view of what's going on.
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Old 1st February 2015, 01:34 PM   #63
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Originally Posted by Donn View Post
Dug your post, loved the typo. It looks like suss + rival, which is a gene's eye view of what's going on.
Seems I had a lot of typos, in fact.
Sorry about that.

Hans
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Old 1st February 2015, 03:31 PM   #64
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Originally Posted by Mashuna View Post
I believe that Jewish men have been conducting an experiment to test whether Lamarkian evolution is true, for a few thousand years now.
Originally Posted by Darwin123 View Post
And Moslems. It is a shame that the foreskin hasn't disappeared over all this time, though.

http://en.wikipedia.org/wiki/Phimosis
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Old 1st February 2015, 04:07 PM   #65
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Originally Posted by wogoga View Post



http://en.wikipedia.org/wiki/Phimosis
Well, that's it, then. We can all go home. Darwin is disproved. All hail Lamarck.
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Old 1st February 2015, 04:15 PM   #66
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Originally Posted by marplots View Post
They don't have to be mutually exclusive, in the sense that Darwinian mechanisms could produce the Lamarckian process, or something that accomplishes much the same thing.

On the surface, it does seem like it would enhance survival - the ability to adapt directly to your immediate environment and pass the ability on to your offspring, giving them a directed "jump start."
Not if an animal broke a leg and passed that on.
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Old 1st February 2015, 05:55 PM   #67
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Originally Posted by tsig View Post
Not if an animal broke a leg and passed that on.
If a broken leg gets you more sex, a broken leg is favored.
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Old 1st February 2015, 08:08 PM   #68
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Originally Posted by marplots View Post
If a broken leg gets you more sex, a broken leg is favored.
A broken leg gives you a stiff peg?
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Old 1st February 2015, 09:08 PM   #69
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Originally Posted by tsig View Post
A broken leg gives you a stiff peg?
Well, a severed leg around the late seventeenth century might.
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Old 1st February 2015, 09:26 PM   #70
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Originally Posted by Darwin123 View Post
And Moslems.
,,, and a few of us who grew up in a Protestant church
Quote:
It is a shame that the foreskin hasn't disappeared over all this time, though.
Its a miracle!
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Old 2nd February 2015, 05:06 AM   #71
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Originally Posted by Nonpareil View Post
Well, a severed leg around the late seventeenth century might.
I lost mine in the late seventeenth century, but since then I've gotten used to it.
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Old 2nd February 2015, 08:03 AM   #72
Foster Zygote
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Originally Posted by Maartenn100 View Post
Darwin is the leading theory. And many biologists are defending Darwin against creationism.

But I have the following questions about the possibility of Lamarckism:

For example, some people are black and other peole are white.
Because of the climate, I would say. The sun in Afrika will give rise to black people.
Why were there no white people in the African lands, many years ago?
People here in Europe are white because of the climate too.

There are Tibitans in the mountains who can survive there. Did they survive because of natural selection or because of genetic adaptation (Lamarck)?
It's more obvious to think that their genes adapted themselves.
"Lamarckism" has come to refer to the idea that individuals inherit traits acquired by their parents. Rather unfortunate for Lamarckism because this idea was only a tiny aspect of his overall work and was widely accepted within the naturalist community of his day. An example of such an acquired characteristic would be a blacksmith with muscular arms passing that trait on to his son. Genetic science has shown that it doesn't work that way.

The reason people in different climates have different levels of melanin concentration in their skin has to do with natural selection of random genetic variations present at birth. Melanin helps protect against ultraviolet radiation from the Sun. Individuals with more melanin producing cells will be better protected from developing skin cancer due to high exposure to sunlight in equatorial regions such as Africa, where humans first evolved. But UV radiation is also needed for the synthesis of vitamin D in the skin. As humans gradually migrated into regions with less and less sunlight exposure, those individuals with genetic traits for less melanin were more likely to be able to synthesize vitamin D and thus experienced somewhat better reproductive success, passing on the trait for less melanin to their offspring.

The reason that people with more melanin are able to survive without the threat of vitamin D deficiency in places like northern Europe today is because vitamin supplements are widely available and are often added to foods.
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Old 2nd February 2015, 04:25 PM   #73
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Originally Posted by Foster Zygote View Post
The reason people in different climates have different levels of melanin concentration in their skin has to do with natural selection of random genetic variations present at birth. Melanin helps protect against ultraviolet radiation from the Sun. Individuals with more melanin producing cells will be better protected from developing skin cancer due to high exposure to sunlight in equatorial regions such as Africa, where humans first evolved.
As it turns out, protection from skin cancer is not the only advantage melanin brings. It turns out that the UV in sunlight destroys vitamin B. So in sun climates, people with low melanin levels have a higher tendency to suffer from vitamin B deficiency.

One of the earlier replies gives a citation link to a study relating vitamin B deficiency to UV. The study seemed to indicate that for people who had 'normal' levels of melanin (i.e., not albino), before vitamin supplements and international shipping of food, vitamin B deficiency is much more of a threat then skin cancer.

So there was a fitness tradeoff before 'advanced' transportation. Too much melanin in a high sunlight habitat, vitamin B deficiency. Natural selection favors pale people in such a habitat. Too little melanin in a low sunlight habitat, vitamin D deficiency. Natural selection favors dark people in such a habitat.

Lamarkian evolution is not necessary to explain most variations in inherited pigmentation. However, I wonder if Darwinian evolution is sufficient to explain all variations in inherited pigmentation. For instance, does a vitamin deficiency in the parent affect the pigmentation inherited by the offspring? So far as I know, no one has done a study on that. However, this correlation is certainly not obvious the way the OP presents it.
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Old 2nd February 2015, 08:20 PM   #74
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Originally Posted by Darwin123 View Post
For instance, does a vitamin deficiency in the parent affect the pigmentation inherited by the offspring?
How do you propose it could do that?

The germ line - egg and sperm - carry already established genetic code to offspring.

Now maybe a sickly individual could have more mutations due to illness*, but in that case the changes would still be random, not Lamarckian in any way.


*And I don't know if that's even possible. Anyone?
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Old 3rd February 2015, 09:57 AM   #75
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Originally Posted by Fast Eddie B View Post
"So the only reasonable explanation of McDougall's experiment seems to be the psychon thesis. All facts are consistent with this reincarnation theory."

Wow!

The explanation just before the above conclusion:
"The inheritance of acquired habits cannot explain the increasing facility in learning of the control line rats which have no trained ancestors. The selection theory is disproved by the experiments with adverse selection. The fact that rats of other stocks did not improve in learning is not consistent with the theory of morphogenetic fields as proposed by Rupert Sheldrake." (Source)
The control-line rats of generation 2 made lots of errors before learning the task going against their normal instinctive behavior. The error numbers of these seven rats are: 24, 30, 35, 36, 36, 37, and 56. In generation 20, two control-line rats knew instinctively the correct solution without committing a single error. Yet they had no trained ancestors, and no Darwinian selection had taken place.

Thus, everybody dealing with this experiment in an unprejudiced way has to subscribe to my above conclusion. And Darwinian selection as the main (or only) mechanism of biological evolution is simply disproved by adverse selection experiments:
The animals with the most successful strategies are not allowed to reproduce, but the animals with the least successful are allowed. And such experiments have shown that despite adverse selection the successful strategies propagate!
Cheers, Wolfgang
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Old 3rd February 2015, 11:27 AM   #76
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Originally Posted by Fast Eddie B View Post
How do you propose it could do that?

The germ line - egg and sperm - carry already established genetic code to offspring.

Now maybe a sickly individual could have more mutations due to illness*, but in that case the changes would still be random, not Lamarckian in any way.


*And I don't know if that's even possible. Anyone?
There is evidence* that bacteria do experience more mutations when under environmental stress - which would have the effect of increasing the mutation rate and thus the evolution rate just when needed. However as you pointed out, this is completely Darwinian, and the vast majority of the mutations would be harmful - it is just that if the current "template" isn't working so well, then some changes to it might just be better.




*CBA to search for it.
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Old 3rd February 2015, 11:29 AM   #77
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Originally Posted by wogoga View Post
The explanation just before the above conclusion:
"The inheritance of acquired habits cannot explain the increasing facility in learning of the control line rats which have no trained ancestors. The selection theory is disproved by the experiments with adverse selection. The fact that rats of other stocks did not improve in learning is not consistent with the theory of morphogenetic fields as proposed by Rupert Sheldrake." (Source)
The control-line rats of generation 2 made lots of errors before learning the task going against their normal instinctive behavior. The error numbers of these seven rats are: 24, 30, 35, 36, 36, 37, and 56. In generation 20, two control-line rats knew instinctively the correct solution without committing a single error. Yet they had no trained ancestors, and no Darwinian selection had taken place.

Thus, everybody dealing with this experiment in an unprejudiced way has to subscribe to my above conclusion. And Darwinian selection as the main (or only) mechanism of biological evolution is simply disproved by adverse selection experiments:
The animals with the most successful strategies are not allowed to reproduce, but the animals with the least successful are allowed. And such experiments have shown that despite adverse selection the successful strategies propagate!
Cheers, Wolfgang
Also from your source:
Quote:
The facility in learning the task is transmitted not through genes but through reincarnation. For an improvement in learning, it is necessary that the souls of the offspring are the souls of the rats which have done the experiment earlier.
If the "successful strategies" propagated, but not, as you yourself say, in rats that were descendants of the "animals with the most successful strategies" (they were "not allowed to reproduce"), while your "psychon theory" of reincarnation requires them to be- how is that theory supported? Whether the theory results in the "acquired habits" being so acquired through a Lamarckian process or one of reincarnation is irrelevant- you've disproven both mechanisms by the same test.

This also seems a little wonky:
Quote:
It is reasonable to assume a certain amount of fluctuation in the souls of the rats. The average rate of learning of all rats in each generation is not a satisfactory method to test the psychon thesis because the average is unduly affected by the appearance of rats which never or only rarely have done the experiment in former lives. Therefore only the ten quickest learners of the trained and the control line are considered in the following table.
IOW, you fiddled with the numbers to fit, not one, but two assumptions- the "certain amount of fluctuation in the souls of the rats," and that rats have souls capable of carrying their "successful strategies" over from one generation to the next (which, as I've said, you actually disproved by not allowing the rats with the successful strategies to reproduce). You begged the question by automatically equating "bright" rats with "reincarnated" rats, and discarding as "not satisfactory" an average that might have proved that (on average) no rats have reincarnated souls.
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Old 3rd February 2015, 01:07 PM   #78
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Originally Posted by turingtest View Post
IOW, you fiddled with the numbers to.. begged the question by automatically equating "bright" rats with "reincarnated" rats, and discarding as "not satisfactory" an average that might have proved that (on average) no rats have reincarnated souls.
Damn turingtest, you actually waded into the septic tank and caulked it! You need a medal.
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Old 3rd February 2015, 03:23 PM   #79
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Originally Posted by Fast Eddie B View Post
How do you propose it could do that?
I don't know. It seems extremely unlikely. It doesn't seem any more likely than starved mothers giving birth to undersized children and undersized grandchildren, even when nutrition is restored. I conjecture that a similar effect in skin pigmentation is possible. It seems to me that vitamin deficiency could turn associated genes on or off.

Maybe the OP read of such a study. Maybe when he says 'it is obvious', he really means 'I read an epigenetic study that makes that claim.' I was making the suggestion to give the OP an opportunity to cite the appropriate study. I was pointing out that such a claim is not entirely inconsistent with 'mainstream science.'

Environmental changes in a parent can turn certain genes on or off. The state of expression can be transmitted to future generations until some other environmental effect changes them back.

A lot of research is being done on epigenetics. There are morphological changes that are carried through into other generations through RNA and protein molecules. Maybe the OP heard of such a study involving skin pigmentation. Maybe....




Originally Posted by Fast Eddie B View Post
*And I don't know if that's even possible. Anyone?
I didn't say that it is possible. I was calling for speculation as to how such a thing could happen.
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Old 3rd February 2015, 04:22 PM   #80
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Originally Posted by Darwin123 View Post

Environmental changes in a parent can turn certain genes on or off.
Is this true of germ line genes?
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