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Author | Topic: Questions on "Random" Mutations | |||||||||||||||||||||||||||||||
MartinV  Suspended Member (Idle past 5856 days) Posts: 502 From: Slovakia, Bratislava Joined: |
One of the most claimed and unproved darwinian statement is that behind evolution stands random mutation as the source of novelties. Both natural selection and drift (ultra selectionists vs neutral- driftists) depends on them.
In his latest article in NYT R. Dawkins (there is no free access anymore to it, but the link to it's transcription is on the bottom of my post) took for granted that random mutation is responsible for dog's diversity. Breeders would be surprised by such a statement. They only pick up desirable characteristics by combining of existing alleles. If those alleles arouse via random mutation is questionable. We cannot breed lizards or tigers - obviously desirable alleles are not present or those species do not mutate. Dawkins btw. ridiculed Behe using this argument:
quote: But this is obviously just a story:
quote: Not Found - The New York Times
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MartinV  Suspended Member (Idle past 5856 days) Posts: 502 From: Slovakia, Bratislava Joined: |
Not at all. You haven't read the first part of my post. But I underestand you are ashamed reading Dawkins arguments.
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MartinV  Suspended Member (Idle past 5856 days) Posts: 502 From: Slovakia, Bratislava Joined: |
I somehow didn't claim that mutations do not exist or are bad/positive. What I claimed is that mutation and natural selection/neutral drift do not lead to speciation. It would be observed if it were true. Artificial selection is used many thousands years. We have a lot of experience with it. Species do not change by random mutation and natural selection. There must be some other forces behind evolution.
It took a lot of time till 19 century that idea of natural selection as one of the sourcees of speciation appeared. Breeders of many generations and civilisation somehow didn't notice the simple fact. Dawkins mentioned only mutation in dogs. The other question is why we can't breed lizards or tigers. Either there are not alleles that can be used for domestication or these species do not mutate.
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MartinV  Suspended Member (Idle past 5856 days) Posts: 502 From: Slovakia, Bratislava Joined: |
That's right Modulous. You have said it more precisely. Dogs had massive genetic diversity before domestification. Lizards and tigers don't possess such genetic diversity and consequently they cannot be domesticated. According Flegr this fact can be explained by a hypothesis that dogs evolved only recently, the other species are evolutionary older and frozen. So or so the case doesn't prove that alleles in dogs arouse by random mutation.
I was questioned also if there was any attempt to create new species by breeding throughout history. Dogs are a good example. They are very diversified but they are the same species. Why using massive breeding many thousands years there are no descendant species? Because selection itself cannot create new species. Breeders know it very well and that's why an idea of selection as source of speciation never occured to them. So simple idea has to wait until midst 19 century to be discovered by Darwin. On my opinion natural selection just removes extremities and is purely conservative force. Edited by MartinV, : former student of theology deleted
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MartinV  Suspended Member (Idle past 5856 days) Posts: 502 From: Slovakia, Bratislava Joined: |
quote: But most programs do not copy themselves nowadays. Most of them have their "creator". Another example is evolution of programming languages. If another civilisation digged up in year 20.000 some big shop's computer network it wouldn't be correct making assumption that language Java running on servers evolved by RM/NS from some outdated host language like Fortran, Algol or PL/1. Even if both language have "If" and "End-if" clause it doesn't mean they have common ancestor or even creator. In fact both languages have independent origin. So extrapolating experience with TIERRA (let say civilization in year 20.000 use only this language) to history of "evolution" of programs and programming languages would be misleading.
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MartinV  Suspended Member (Idle past 5856 days) Posts: 502 From: Slovakia, Bratislava Joined: |
You probably didn't read the latest Dr.Ad's post. If true I don't see problem that in year 20.000 there will be self-programming and self-replicating artificial systems available. Anyway extrapolating their history from studying their most recent self-development could be misleading because of conclusion that there was no intelligent creator first and process arouse once "by chance".
Edited by MartinV, : No reason given.
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MartinV  Suspended Member (Idle past 5856 days) Posts: 502 From: Slovakia, Bratislava Joined: |
quote: My example is as ridiculous as Dawkins example of rowers in rowing-boats in Selfish gene. Or example of apes writing on typewriters Shakespeare's play. Programming languages are on my opinion very good example. Of course natural languages would be better example. French academy do not accept treteases on origin of languages since 19 century. No one can with certainity claims how human languages arouse and evolved. Anyway I didn't hear that words in Indo-European languages arouse by random mutation of words of Sanskrit. I mean the problem is little bit more complicated.
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MartinV  Suspended Member (Idle past 5856 days) Posts: 502 From: Slovakia, Bratislava Joined: |
And so of course I have not done so, as you would know if you'd actually read my post instead of wittering on about the first thing that popped into your head when you noticed that I'd mentioned evolution and programming languages in the same post.
You are right, I have never read your posts very carefully. But somehow it happened that one of your sentences reminded me of the evolution of languages. It has nothing to do with your "specific ideas" in your post you know. Actually it has nothing to do with your post full of "specific ideas". Sorry.
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MartinV  Suspended Member (Idle past 5856 days) Posts: 502 From: Slovakia, Bratislava Joined: |
Except that Dawkins managed to construct the metaphor in such a way that the rower teams would reproduce and the rowers (and their position) were heritable traits. It was intended to show that genes can benefit through selfish cooperation, and it worked. You need to have replication and heritable traits in your example before it can have the same level of validity as this.
First let us remind ourselves what Richard Dawkins said:
quote: Obviously it is Richard Dawkins not me who forgot on replication and heritable traits. In the next generation "individual oarsman" will be in completely different team of oarsmen. It is hardly imaginable that other oarsmen have (are) only one allele. There are always many oarsmen (alleles). So each allele will be sitting in the next generation in almost completely different set of alleles (crew). Each individual (boat, crew) is unique genotyp. There are not the same genotypes - except true twins. There are always different phenotypes(speed of the boat). Because of this the effect of each individual allele will be different in each generation and each genotype. The effect of an allele depends predominantly on the mix of other alleles. The influence of an allele sitting in unique set of other different alleles to the phenotype and its fitness is always different. There is no doubt some alleles are detrimental and will be removed by NS. But other alleles and genes influence each other and the outcome depends on their mix which is in each generation different. Obviously there is no Dawkins hypothetical relation between an individual allele and fitness of the phenotype. -----------------For instance, roughly 85% of the genetic diversity among humans is found within populations... heterozygosity of autosomal microsatellites... humans 0,776.
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MartinV  Suspended Member (Idle past 5856 days) Posts: 502 From: Slovakia, Bratislava Joined: |
quote: I don't see a point. Let say we have at the beginning 1.000 Englismen and 500 German. If individuals are not passed on the number of individuals would decrease each race. After some rounds we would have 50 sportsmen, Englismen and German separated to their own boats. We would have homozygous groups - all German or all English. Any mix would be detrimental. It is something we do not observe in the Nature - heterozygosity is great as my previous post mentioned: 0,77 in humans.
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MartinV  Suspended Member (Idle past 5856 days) Posts: 502 From: Slovakia, Bratislava Joined: |
Oh, for pity's sake.
Don't bother respond my posts. I am not interested in your opinion that reminds me of those singletons at AtBC.
It's got nothing to to with heterozygosity. He's talking about how recombination and selection produces set of genes --- different genes, DIFFERENT GENES --- which are suited to one another.
Hehehe, DIFFERENT GENES. Because Dawkins wrote about genes, not alleles. The exapmle he had given is for people who had no idea about genes. People that do not use their brain very often - but often use abuses and capital letters on the discussion forums instead. Such people consider themselves to be very wise but have little knowledge about geography and biology. The others know that scientists are interested in frequency of alleles in given population. Dawkins example has nothing to do with reality. Population is in many cases of genes polymorphic. Heterozygosity in humans is 0,77%! It means that DIFFERENT GENES are present in many variations, compositions. In sexual reproduced organisms an allele is in each generation in a different company of another alleles. There is no such thing as boat of rower-men who have the same place over generations - homozygous you know (maybe except of supergenes). On the place 1 is rower A (allele) in first generation. In the next generation in the place 1 is rower B ( and A is present but recessive - he rest). In the third generation it is again rower B but in the fourth it is A. But now the place 2,3,4,5 are occupied by rowers (alleles) completely different than in the first generation. So if the benefit of an allele in the first generation was positive it may happen that in the crew of the fourth generation the same allele could be slightly detrimental. That's why the concept of selfish gene is very weird - the crew (genotype) is always different.
Of course you don't see the point. You never see the point of anything. This is because, as you admitted, you don't bother to read the things you're pretending to reply to. As I said, it's not a Rorschach test. The point of what Dawkins wrote is not the subconscious ideas it stirs up in your head after you skim-read it and pick out a few words.
Calm down. Before you write another intelligent post full of denigration try to consider for a moment to genetic interactions and epistatic interactions. Try to explain why Dawkins do not considered them in his "DIFFERENT GENE" example.
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MartinV  Suspended Member (Idle past 5856 days) Posts: 502 From: Slovakia, Bratislava Joined: |
quote: You don't think. You just repeat Dawkins arguments like a parrot. Obviously you don't see difference between alleles and genes and that GENES are polymorphic. Because you don't realize that phenotyp of a sexualy reproduced organism is the result of genetic and epistatic interactions of genotype which is in each generation different you consider story about "GENES in boat" as wonderful. You consider any close insight and change of "GENE boat" for more realistic "Allele boat" only as "babbling". Edited by MartinV, : No reason given.
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