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Bobwundaye's Avatar Comment 1 by Bobwundaye

Professor Bauer from the university of Freiburg, which argued, that epigenetics show, that the selfish-gene-theory is not true, and i think, that the book The Selfish Gene did the same

Consestor, could you elaborate on Professor Bauer's reasoning?

Fri, 08 Jul 2011 04:00:23 UTC | #847543

Anaximander's Avatar Comment 2 by Anaximander

Professor Bauer from the university of Freiburg, which argued, that epigenetics show, that the selfish-gene-theory is not true, and i think, that the book The Selfish Gene did the same.

The Selfish Gene did show that the selfish-gene-theory is not true?

Fri, 08 Jul 2011 06:34:24 UTC | #847568

Jos Gibbons's Avatar Comment 3 by Jos Gibbons

As far as I understand it consestor is asking us to tease out Bauer's reasoning so could not expand on it him/herself. I've never heard of Bauer or his book, but Google soon fixes that. His publications listed here do not include the book and his research here does not include epigenetics or the extent to which a gene is selfish or cooperative. He nonetheless did write such a book. Searching for the German name yields an Amazon page, whose translation into English I've used to find out what I could about Bauer's argument. The front cover of the book calls him "Joachim Bauer". Maybe G is an initial based on an English equivalent, or maybe I have the wrong book. (It wouldn't be the first time; see below.) Amazon does mention Freiburg ties, however, so I suspect it's the same man. The book's subtitle, "Farewell to Darwinism", is every bit as ambitious as consestor made Bauer sound. Amazon doesn't give exhaustive descriptions of its books' conclusions or arguments, and the main page only shows select reviews. Ctrl F found only one part of the page even mentioning epigenetics, and it is this extract I've taken from a translation of a review which gives the book 1 star:

In recent decades, many genes have been deciphered, mutation basics and essential processes of gene regulation understood, discovered epigenetic processes and the emergence and importance of mobile elements in the genome. It was also discovered that may affect the cell or organism acting stress factors in incidence and prevalence of these mobile genetic elements. Bauer thus builds on a bubble and the reader tries to make clear that it may come Thanks to this stress-induced "conversion thrusts" of the genome to adaptive changes, and therefore we can forget about Darwin's selection hypothesis to a large extent. This is of course nonsense, since it would be assumed that the self-induced remodeling of the genome is done in an adaptive direction. The fact is that through these processes only variation occurs can affect the classical selection and thus adaptation over generations to come about.Likewise, the evolution of epigenetic regulation is the result of traditional selection processes.

In other words, the response Dawkins would give to Bauer's proposed alternative mechanism, if he responded at all, would be the same as he gives to Lamarckism: it still needs Darwinism to work.

Interestingly, if one searches for the English version of the name, all we get is a book of the same name due to geneticist Mark Ridley, and it has this subtitle: How Mendel's demon explains the evolution of complex beings. Unlike Maxwell's demon, Mendel's demon is not the title of a Wikipedia article; indeed, if one searches Google for it, all one gets is a book of that name also by Mark Ridley, "Mendel's Demon: Gene Justice and the Complexity of Life". Though I've not yet read Bauer's book, I read Ridley's a few years ago. An explanation of the demon may be found in this review of Ridley's book:

Sexual reproduction, including the curious process of meiosis, in which the number of chromosomes in the gametes is halved, is, according to Ridley, a means whereby copying errors are controlled, potential conflicts are resolved, and information is randomized effectively enough to allow the evolution of complex organisms such as ourselves. This is Mendel's demon (the expression derives from Maxwell's demon, meaning something that biases random processes in a particular direction); Mendel's demon has shifted evolution in the direction of complexity. Meiosis increases the uncertainty about which other gametes, or offspring, contain copies of a gene, and this stops, or almost stops, the evolution of the most damaging forms of selfish genes.

Clearly Ridley does not have the same anti-Darwinian ambitions as Bauer does.

Fri, 08 Jul 2011 07:41:07 UTC | #847577

Alex, adv. diab.'s Avatar Comment 4 by Alex, adv. diab.

Meh, Freiburg. full of Hippies! ;)

Anyhew, maybe we really get an answer from muster dawkins personally, but I've never quite understood what profound problem epigenetics should pose for a gene-based view of evolution. If I remember correctly, epigenetic information certainly interferes with how genes are expressed in individuals or even their ancestors, so it can influence fitness of individuals, but it does not change the genome. It is more like an environmental variable which influences which genes potentially enhance fitness and which don't, but for long term and profound changes, like speciation, the genome has to change, and there gene exchange and mutations filtered by natural selection comes into play, there's no way around that. It would be interesting what Bauer says in more detail, can you give a succinct summary?

Fri, 08 Jul 2011 08:37:32 UTC | #847585

DavidMcC's Avatar Comment 5 by DavidMcC

Comment 4 by Alex, adv. diab. :

Meh, Freiburg. full of Hippies! ;) Anyhew, maybe we really get an answer from muster dawkins personally, but I've never quite understood what profound problem epigenetics should pose for a gene-based view of evolution. If I remember correctly, epigenetic information certainly interferes with how genes are expressed in individuals or even their ancestors, so it can influence fitness of individuals, but it does not change the genome.

I agree, and so would any reptile, as the gender of their offspring depends on the temperature that the egg is held at during incubation. If that isn't important to their evolution, then what is? Of course it was previous genetic evolution that must have lead to that situation (because we don't have the same issues as turtles), so it isn't entirely unrelated to genes, which do, after all, code for the molecules that react to form the molecules, etc ... that epigenetically modify the expression of genes. Actually, the processes of early embryonic development, and of gene expression itself, are inherently partly epigenetic. I think it's a significant part of modern neo-Darwinism.

Fri, 08 Jul 2011 09:55:25 UTC | #847598

Alan4discussion's Avatar Comment 6 by Alan4discussion

@ CONSESTOR

The Cooperative Gene (Das kooperative Gen) by a biologist Professor Bauer from the university of Freiburg, which argued, that epigenetics show, that the selfish-gene-theory is not true, and i think, that the book The Selfish Gene did the same....

I have seen epigenetics used by creationists as a (false) revival of Lamarkian adaptation. As I understand it, there is some fringe research to support it as a property of a very limited number of genes (a fraction of 1% of a genome), producing often transitory effects in one or two generations of offspring,- the basis of which is unclear. It in no way challenges the "selfish gene" or Darwinian genetics in general. It is a minor irregular variation in phenotype expression.

In terms of scientific standing, a couple of hairs on the tail, do not wag the dog!

Fri, 08 Jul 2011 10:39:57 UTC | #847609

Absinthius's Avatar Comment 7 by Absinthius

As I have been tought, one of the first steps after fertilization of an Oocyte is a more or less epigenetic-reset of the newly formed diploid cell. Epigenetics plays a pretty big role in differentiation of cells and of course also to a certain extent in the ''succes" an individual organism might have in propagating it's genes. But I don't really see how this is incompatible with the selfish gene theory. As the offspring of organisms will be epigentically more or less neutral.

Differences in the gene-code itself due to pointmutations or somesuch mechanism, regardless of epigenetics are a lot more persistant between generations. Of course there are ways epigenetics can play a more lasting role. For example CpG sites in the DNA can be epigenetically regulated to form a methylated Cytosine. And it has been shown that during replication, a methylated Cytosine has an increased chance to be copied as a Thymine in the new DNA strand. This of course can result in epigenetics-driven permanent changes in the gene code.

Fri, 08 Jul 2011 11:29:41 UTC | #847619

consestor's Avatar Comment 8 by consestor

@ Anaximander Sorry, I meant the Book The Selfish Genius, I think a part of it was published here in New Scientist: http://www.newscientist.com/article/mg20327176.800-comment-the-dawkins-dogma.html Bauer argues, that in stress situations the genome of the organism actively reacts on this by "activating" jumping genes(transposons) and doubling some other genes, so the organism gets adapted to the new sitiuations.......I think he was supported by Professor James A. Shapiro from the University of Chicago, who made his view on the mechanisms of evolution clear in this paper: http://shapiro.bsd.uchicago.edu/Shapiro.2005.Gene.pdf. And I am very confused about these things, because I have never read about it in the writings of very known scientists like Professor Dawkins, Stephen Gould or Jerry Coyne.

Fri, 08 Jul 2011 12:01:20 UTC | #847628

DavidMcC's Avatar Comment 9 by DavidMcC

Comment 6 by Alan4discussion :

I have seen epigenetics used by creationists as a (false) revival of Lamarkian adaptation. As I understand it, there is some fringe research to support it as a property of a very limited number of genes (a fraction of 1% of a genome), producing often transitory effects in one or two generations of offspring,- the basis of which is unclear. It in no way challenges the "selfish gene" or Darwinian genetics in general. It is a minor irregular variation in phenotype expression.

In terms of scientific standing, a couple of hairs on the tail, do not wag the dog!

I hope you're not inferring from that that epigenetics is just Lamarckianism. That would be seriously incorrect.

Fri, 08 Jul 2011 13:30:55 UTC | #847655

Sean_W's Avatar Comment 10 by Sean_W

Oh, Meh, Freiburg. full of Hippies! ;), that's just eerie.

Fri, 08 Jul 2011 15:30:43 UTC | #847696

Alan4discussion's Avatar Comment 11 by Alan4discussion

Comment 9 by DavidMcC

I hope you're not inferring from that that epigenetics is just Lamarckianism. That would be seriously incorrect.

Nope! That would indeed be incorrect! I am suggesting that I have seen creationists try to infer that this challenges established concepts of genetic inheritance.

Fri, 08 Jul 2011 15:50:28 UTC | #847702

Neodarwinian's Avatar Comment 12 by Neodarwinian

Sounds as the rather typical piece of the puzzle advanced as the whole puzzle solved argument. Claims made by Gould, Roughgarden, Margulis and some others fall into this catagory. Epigenetics are an important part of biology but a part of biology, not precluding other findings in biology.

Fri, 08 Jul 2011 17:18:36 UTC | #847727

pzkrakz's Avatar Comment 13 by pzkrakz

I am naive to Dr. Dawkin's comments on why epigenetics is not important (I am sure there is some context to this that is missing), but clearly epigentic factors play a role in many aspects of development and disease. DNA methylation can control gene expression directly, whereas histone modification can regulate access to chromatin, and exposure of genes for transcription. Also, miRNA, a newly discovered set of master controlling elements, appear to have epigenetic effects, or be regulated epigenetically.

So, as it relates to disease, development, and understanding cellular control mechanisms, epigenetics is a critical field. On long evolutionary time scales, it may be that epigenetic heritability is not sustained (I am not sure). Even if that is the case, DNA mutations that impact sites which control DNA methylation, or histone modification, would have a significant impact on the fate of an organism.

Fri, 08 Jul 2011 17:23:02 UTC | #847733

keyfeatures's Avatar Comment 14 by keyfeatures

So is this a sort of 'knowing' gene theory?

Presumably the epigenetic parameters are entirely set by the gene. These parameters would logically therefore simply be an extended function of survival strategy. The gene would still be acting 'selfishly'....unless perhaps there is a function for self-destruction within such epigenetic parameters?

Fri, 08 Jul 2011 18:51:14 UTC | #847760

davidpercival's Avatar Comment 15 by davidpercival

A posting on 29th.June by Rara192 called Fussy Finches Choose Sons discussed an interesting experiment in Australia using Gouldian finches.

These finches have a number of different head colours, the predominant ones being red and black. It is known that breeding is normally with the same colour heads but occasionally the red and black heads do mate. The offspring of such matings are generally less viable than normal but the males so produced are likely to survive much better than the females. Interestingly these red/black unions where they occur have four males produced for every one female.

The experiment involved painting the heads of some of the males so that a red headed female mated with a red headed male (who had been painted black). You would think that because of the genetic inheritance the offspring would be normal in sex ratio but in fact it turned out that there were four males for every female - exactly the same as there would have been if they had mated with a real black headed male.

Only 10 comments were made on this (including two of mine and one by the original poster). On the face of it this experiment is clear evidence of epigenetic changes.

On a slightly different note, I have contributed on this site over the last few months mentioning apparent instances of Lamarckian inheritance in nemotodes, chickens, rats and mice (quoting from impeccable scientific sources). In the case of chickens Richard Dawkins commented rather testily that the full reference to the scientific paper was required. This was supplied quickly but he did not intervene in the lively exchanges which followed.

The poster of the current thread asks us to speculate as to why Richard Dawkins has such a low opinion of the importance of epigenetics. Perhaps all neo Darwinists find it impossible to believe that there can be any other explanation for evolution and automatically reject any other factor having an influence?

Fri, 08 Jul 2011 20:43:33 UTC | #847799

Alan4discussion's Avatar Comment 16 by Alan4discussion

Comment 15 by davidpercival

On a slightly different note, I have contributed on this site over the last few months mentioning apparent instances of Lamarckian inheritance in nemotodes, chickens, rats and mice (quoting from impeccable scientific sources). In the case of chickens Richard Dawkins commented rather testily that the full reference to the scientific paper was required. This was supplied quickly but he did not intervene in the lively exchanges which followed.

The poster of the current thread asks us to speculate as to why Richard Dawkins has such a low opinion of the importance of epigenetics. Perhaps all neo Darwinists find it impossible to believe that there can be any other explanation for evolution and automatically reject any other factor having an influence?

There is no alternative "other explanation for evolution". As far as inherited characteristics are concerned, epigenetics is a superficial side issue, as I commented @6 & @11.

Fri, 08 Jul 2011 23:29:52 UTC | #847827

ccw95005's Avatar Comment 17 by ccw95005

As I understand it, epigenetic characteristics only stick for a few generations, at most. So it's unlikely that they are part of permanent change. However - the interesting thing is that the capacity for epigenetics IS probably part of the genome. In other words, the ability to bring about temporary changes in the phenotype is probably something that evolution handed to at least some of Earth's creatures. That's a concept I'll have to think about, now that it's struck me. Probably other people have thought about it quite a bit. I suspect that the ability to adjust to a changing environment more quickly than classic genetic evolution was important in some circumstances. But it's mind boggling to think of how natural selection would have invented epigenetics, through favorable incremental changes. Smart as hell, that evolution.

Sat, 09 Jul 2011 03:27:57 UTC | #847867

DavidMcC's Avatar Comment 18 by DavidMcC

Ccw, evolution didn't have to invent epigenetics, which is inherent in biology, even from the earliest stage of embryonic development. It merely exploits it. Some species/groups do so more than others. Eg, reptiles don't have sex chromosomes, because of temperature effects. Also (IMO), guppies exploit it for their "quick change" trick that enables them to "make hay while the sun shines (not literally!)" with the minimum of delay.

EDIT: Obviously, I need confirmation on guppies, but I suspect it is the case, as they re-invent their colouration too quickly for NS, even with sexual selection, IMO.

Sat, 09 Jul 2011 10:08:22 UTC | #847924

consestor's Avatar Comment 19 by consestor

I do not understand why epigenetics should be that unimportant, if the genome reacts to stress situations as it is considered in this paper http://shapiro.bsd.uchicago.edu/Shapiro.2005.Gene.pdf. The key points of this theory of evolution by Prof. Shapiro are presented on p.7f., but the rest of the paper also seems to be very important...

Sat, 09 Jul 2011 11:42:47 UTC | #847940

Daniel O'Malley's Avatar Comment 20 by Daniel O'Malley

I see that epigenetics confirm the selfish gene metaphor. By only influencing the expression of the genome, the genes can avoid the usual scrutiny of natural selection -- They can more dynamically respond to outside pressures, the genes thus get to stay in the population longer. Why shouldn't that be selected from the genes point of view? The genes only need to change their behaviour, if you will, so that they can keep their position in the envirnoment of other genes and up. It is sensationalist to conclude that it overturns all that has been established so far (with evidence backing it up).

Sat, 09 Jul 2011 11:56:42 UTC | #847946

ccw95005's Avatar Comment 21 by ccw95005

Comment 18 by DavidMcC :

Ccw, evolution didn't have to invent epigenetics, which is inherent in biology, even from the earliest stage of embryonic development. It merely exploits it.

You may be right, but I wonder. Let's suppose that way back when, DNA didn't allow epigenetic effects on the phenotype. Then there was a mutation that gave plants or animals that capability. And evolution in its wisdom found that certain temporary changes in the phenotype - without altering the basic genome - were of survival benefit when there were temporary environmental changes. That mutation might well, then, be selected going forward. It almost seems like epigenetics is too complex in its effects to be random.

Sat, 09 Jul 2011 21:17:58 UTC | #848044

davidpercival's Avatar Comment 23 by davidpercival

The Time article is very impressive although it necessarily is not particularly in depth. There are plenty of other examples of epigenetic inheritance. Alan4discussion in Comments 6 and 11 says epigenetics is a fringe issue and he has seen it used by creationists. Well in the first place it can be seen just from the Time article that it is much more than a fringe issue.

The second thing is I can't see how it can be used by creationists as it is totaly supportive of evolution. In fact it could be said that it is an even more radical proposition than Neo Darwinist dogma (I know they don't like the word but it was Crick that coined it and Alan4discussion articulates it exactly as that in comment 16).

The suggestion I have put forward in discussions on this site is that an environmental change could lead to a change in behaviour in one generation which is passed on epigentically to their offspring. If the change in the environment persists the change in behaviour is re-inforced and so on. Random mutations for longer legs and necks would be selected if a previously ground feeding species started to look upwards because of a change in vegitation, for example. This seems to me a much more likely course towards a new species than a randon mutation for long necks appearing and the animal then deciding it would be a good idea to look up rather than down. If the enviromental change ceases then the epigenic changes in behaviour may well fall into disuse and disappear in a few generations but those who accept that epigenetic inheritance takes place to any degree need to explain why it should die out if it continues to help the animal to survive.

My posting "Inheritance of Acquired Behaviour in Chickens" discusses evidence from a brilliant Swedish experiment which seems suggestive of epigenetics in relation to behaviour and gives the reference to view their research.

Sun, 10 Jul 2011 18:22:44 UTC | #848292

keyfeatures's Avatar Comment 24 by keyfeatures

comment 22 by DefenderOfReason

Thanks for a great link.

One small worry about humanity being able to switch off the gene for autism however. Perhaps our genes 'know' better than we do. Autism is not necessarily a bad thing.

Sun, 10 Jul 2011 20:31:42 UTC | #848335

Alex, adv. diab.'s Avatar Comment 25 by Alex, adv. diab.

Comment 10 by manilla_wise

Eeek! where did that come from?

Sun, 10 Jul 2011 22:08:14 UTC | #848367

Alan4discussion's Avatar Comment 26 by Alan4discussion

Comment 23 by davidpercival

The second thing is I can't see how it can be used by creationists as it is totaly supportive of evolution. In fact it could be said that it is an even more radical proposition than Neo Darwinist dogma (I know they don't like the word but it was Crick that coined it and Alan4discussion articulates it exactly as that in comment 16).

Comment 16 rejects the suggestion that there is an "alternative theory to evolution" which argued, (see OP) that epigenetics show, that the selfish-gene-theory is not true, involving Lamarckianism.

I recall this discussion:- http://richarddawkins.net/discussions/543672-inhertitance-of-acquired-behaviour-adaptions-and-brain-gene-expression-in-chickens

I also recall the advice you were given:-

Comment 2 by El Bastardo - Is this what you meant?

http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0006405

I would suggest you have a read through as opposed to skimming for bits you want to see. read it fully, then check out other ideas regarding Epigenetis

Perhaps some thinking about the meaning of epigenetics would be appropriate:

genetics - the study of the functions of genes.

epi - on top of - that is a process of gene expression working on top of (not instead of) the functioning of genes. This may be regulated by other genes, or interfered with by chemicals as in the unfortunate case of Thalidomide, or by environmental conditions such as temperature in crocodiles determining sex.

Epigenetics is a part of normal genetic processes. It is nothing to do with "substitute" theories of evolution. The interesting inherited transient carry over in some species is a minor side issue which may or may not have chemical or environmental origins.

Can epigenetic changes be permanent? Possibly, but it's important to remember that epigenetics isn't evolution. It doesn't change DNA. Epigenetic changes represent a biological response to an environmental stressor. That response can be inherited through many generations via epigenetic marks, but if you remove the environmental pressure, the epigenetic marks will eventually fade, and the DNA code will — over time — begin to revert to its original programming. That's the current thinking, anyway: that only natural selection causes permanent genetic change.

Read more: http://www.time.com/time/magazine/article/0,9171,1952313,00.html#ixzz1RkL1GS4m

Sun, 10 Jul 2011 22:49:49 UTC | #848376

Sean_W's Avatar Comment 27 by Sean_W

Comment 25 by Alex, adv. diab.

A terribly flawed attempt at humor. An easy to produce mispronunciation, similar sounds, and I'm posting Young Frankenstein. As far as I'm concerned it's just another misfiring.

Mon, 11 Jul 2011 00:45:48 UTC | #848400

Alex, adv. diab.'s Avatar Comment 28 by Alex, adv. diab.

Comment 27 by manilla_wise

heh, now I get it. Kinda reminds me of something JFK said.

Mon, 11 Jul 2011 10:25:14 UTC | #848522

DavidMcC's Avatar Comment 29 by DavidMcC

Comment 21 by ccw95005 :

Comment 18 by DavidMcC :

Ccw, evolution didn't have to invent epigenetics, which is inherent in biology, even from the earliest stage of embryonic development. It merely exploits it.

You may be right, but I wonder. Let's suppose that way back when, DNA didn't allow epigenetic effects on the phenotype. Then there was a mutation that gave plants or animals that capability. And evolution in its wisdom found that certain temporary changes in the phenotype - without altering the basic genome - were of survival benefit when there were temporary environmental changes. That mutation might well, then, be selected going forward. It almost seems like epigenetics is too complex in its effects to be random.

Ccw,

a) Reptiles would not exist without epigenetic effects, as they would then only have one sex!

b) Honey bees, for example, would not exist without it, because the queen only becomes a queen by being fed royal jelly as a larva.

Mon, 11 Jul 2011 11:17:11 UTC | #848536

Alex, adv. diab.'s Avatar Comment 30 by Alex, adv. diab.

Comment 29 by DavidMcC

Isn't the whole differentiation of cell types in multicellular organisms already a big epigenetic machinery. It doesn't seem so unreasonable then that this could evolve to include some of the additional epigenetic effects which we talk about now.

Mon, 11 Jul 2011 15:34:31 UTC | #848627