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Author Topic: How big a role does the epigenome play in evolution?  (Read 56213 times)

Offline norcalclimber

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I recently mentioned this when it occurred to me in another topic, but I think it is worthy of its own.

Epigenomic markers seem to allow life to have a degree of control over its own DNA(stickleback fish, and possibly whales are examples of rather large changes brought about by epigenomic markers).  From what I have read, it is still unknown exactly how large or small a part epigenetics has played in macro-evolution.  If epigenomic markers actually allow life to direct mutation to any extent whatsoever, would that qualify as "intelligent design"?

From what I have read, life showed very little evolution over the first ~3.5 billion years it was here.  Then, roughly 750 million years ago, thousands if not millions of new, complex species emerged, and continued to evolve at a breakneck pace when compared with the first ~3.5 billion years of life. 

Could this be evidence that epigenomic markers which permitted some form of directed mutation even if very minor, in other words "intelligent design" first evolved ~750 million years ago?


Edit:  I am by no means referring to creationism or any sort of creator whatsoever.  I have changed the title question to avoid confusion.  The intelligent I was originally referring to is life in general, and individual organisms more specifically.  No omnipotent creator, no "design" by some master force, just a species evolving something because it needed it.
« Last Edit: 19/05/2010 02:05:41 by norcalclimber »


 

Offline JP

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Re: How big a role does the epigenome play in evolution?
« Reply #1 on: 22/03/2010 05:31:16 »
A couple of thoughts, although I'm not an expert in the area.

1) As I understand it from doing a little bit of Googling, epigenetics is basically akin to switching genes on or off in response to the environment, so the genes would already have to be in place to begin with.  If that's the case, then an individual wouldn't be able to spontaneously mutate new genes, only change how the existing genes work.  Therefore, an explosion of new species would probably still be due to more standard Darwinian evolution, wouldn't it?  Also, no one has seen epigenetic traits be passed on for more than a few generations from what I can tell, which would be required for it to contribute to making new species (although the field is in its infancy).

2) Using the phrase "intelligent design" might turn people off of discussing this idea, since that phrase is usually associated with an anti-science religious movement rather than legitimate science.  Also, epigenetics isn't limited to "intelligent" species, is it?  I imagine plants and microbes can also turn on or off genes in response to their environment.

 

Offline norcalclimber

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Re: How big a role does the epigenome play in evolution?
« Reply #2 on: 22/03/2010 15:25:14 »
Epigenetics is akin to switching on or off genes, but there is more to it than that.  There are literally thousands of epigenomic markers for every gene.  We really have no idea the depth to which they affect the whole issue, epigenetics makes the human genome project look like child's play.  I have looked at lots of experiments which showed beneficial mutations, but the only ones I have been able to find, all have one thing in common.  They were all simply mutations of an existing metabolic pathway.  We also see over and over again in experiments, when the environment is stressed life evolves far quicker than we previously thought it could.  It is still unknown whether whales "lost their legs" due to epigenetics, but if so, all DNA could contain far more possibilities than we previously thought.

I assume by "standard Darwinian evolution" you mean with only random mutations, no control to it at all?  The problem with only random mutations, is that the mutation rates for life seems to have changed, and that's would imply a not so random element.  Plus, we know for a fact that life has found at least a small way to influence DNA(epigenomes).  Considering the track record of life, I seriously doubt better epigenetic controls did not evolve.

Using the term "intelligent design" might turn people off, but if they read the post they will see the context.  I use the term because it describes evolution by epigenetic mutation awfully well, and challenges preconceptions.  The discovery of epigenetics challenges a lot of our preconceived notions, predominantly the belief that the only way for DNA to change is through random mutations.  We know now, that many of the large, phenotypical changes may be epigenetic at heart.  Intelligent is a subjective word too, I believe all life has some level of intelligence, including plants, microbes, etc.

I recently watched "Was Darwin Wrong?" by Naked Science, and it further confirmed a lot of what I have been learning.  Watching it, I don't remember hearing the term "random mutation" even once.  At the end, they talked about epigenetics, and how we have learned that life is actually capable of "making" changes, and can evolve much faster than we previously thought.

With this knowledge in hand, the explosion of life ~750 million years ago, with rapid mutation since, seems awfully conspicuous.
 

Offline Geezer

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Re: How big a role does the epigenome play in evolution?
« Reply #3 on: 22/03/2010 21:34:27 »
I agree with JP. The term "Intelligent Design" is loaded with many less than scientific connotations. Unless you subscribe to those concepts, it would be much better to avoid the use of the term.
 

Offline echochartruse

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Re: How big a role does the epigenome play in evolution?
« Reply #4 on: 22/03/2010 23:49:21 »
From what I have read, life showed very little evolution over the first ~3.5 billion years it was here.  Then, roughly 750 million years ago, thousands if not millions of new, complex species emerged, and continued to evolve at a breakneck pace when compared with the first ~3.5 billion years of life. 

Could this be evidence that epigenomic markers which permitted some form of directed mutation even if very minor, in other words "intelligent design" first evolved ~750 million years ago?


Maybe we have not found any evidence from pre 750 million years ago, who knows.
I remember in another forum it was agreed that DNA only carried the information and that Mother Natured controlled it.

It is unfortunate that we try to humanise the process, even by calling it "intelligent Design" we do that but either way mutations occure for a reason. Some mutations from our environment are not all good and fortunately short lasting, some are good, such as larger nostrills for humid weather, larger brows to keep the sun out etc and these seem to be handed down the generations so there must be some type of intelligence about it.
 

Offline echochartruse

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Re: How big a role does the epigenome play in evolution?
« Reply #5 on: 23/03/2010 03:43:00 »
Quote
http://discovermagazine.com/2009/mar/02-evolution-by-intelligent-design “Based on what we know, the artificial chromosome is going to be the best way to modify the genome,” says Lee Silver, a professor of molecular biology and public policy at Princeton University. “Nature doesn’t care about individual children. Instead of rolling the dice, why don’t we take the dice and put them down in the way that parents think is best for their children.” He anticipates the development of specialized artificial chromosomes—a “good health” artificial chromosome, for instance—that could routinely be inserted into human embryos. “You could create a generic version that has lots of good genes like the ones known to protect against cancer, strokes, and heart disease,” Silver says.

Our Post-Darwinian Future
Pluripotent stem cells, gene targeting, and artificial chromosomes could leapfrog over evolution and let us take control of our genome, maybe even turn ourselves into a whole new species. “There is no scientific basis for thinking that we couldn’t,” Silver says. “There’s nothing really special about the human genome. There’s nothing that says this is the end.”.................
Evolution by Intelligent Design
Bioengineers will likely control the future of humans as a species.
by Jane Bosveld published in DISCOVER MAGAZINE From the March 2009 issue; published online February 2, 2009

I'm really counting on these scientists having more intelligents than mother nature.
« Last Edit: 23/03/2010 03:44:58 by echochartruse »
 

Offline LeeE

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Re: How big a role does the epigenome play in evolution?
« Reply #6 on: 23/03/2010 16:47:16 »
The concept of 'Intelligent Design' seems to have clearly evolved from 'Creationism'.
 

Offline echochartruse

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Re: How big a role does the epigenome play in evolution?
« Reply #7 on: 23/03/2010 22:34:36 »
The theory of “Intelligent Design” has been labeled Creationism by some.

Ronald Numbers, Historian of Science at University of Wisconsin, a critic of intelligent design agrees that the easiest way to discredit intelligent design is to associate it with creationism without actually addressing the merits of its case.

A couple of thoughts, although I'm not an expert in the area.

2) Using the phrase "intelligent design" might turn people off of discussing this idea, since that phrase is usually associated with an anti-science religious movement rather than legitimate science.  Also, epigenetics isn't limited to "intelligent" species, is it?  I imagine plants and microbes can also turn on or off genes in response to their environment.

Intelligent Stem Cell Culture Systems (ISCCS) – Just because we call it 'intelligent' do we label it 'creationism'?

Quote
  “Frist, a doctor who graduated from Harvard Medical School, said exposing children to both evolution and intelligent design "doesn't force any particular theory on anyone. I think in a pluralistic society that is the fairest way to go about education and training people for the future."
© 2010 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.

Most cells in the human body are not human. They are microbial at a ratio of 10:1. More than 1,000 bacterial species live in us. Depending on the food source, our environment, soil, atmosphere, etc. Microbes may have either beneficial roles in maintaining life or undesirable roles in causing human, animals and plant disease. These microbes that live inside us (populate our bodies) determine our physiology and our health.  Without the co existence of these microbes and their ability to alter gene expression in specific host environments we would not survive.

"alter our gene expression"... darn intelligent microbes!
 

Offline Geezer

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Re: How big a role does the epigenome play in evolution?
« Reply #8 on: 24/03/2010 02:29:31 »

The theory of “Intelligent Design” has been labeled Creationism by some.


As far as I am aware, there is no theory of intelligent design. If there is such a theory it would be good to have that theory submitted to a peer review, and publish the results.
 

Offline echochartruse

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Re: How big a role does the epigenome play in evolution?
« Reply #9 on: 24/03/2010 03:23:47 »
Could this be evidence that epigenomic markers which permitted some form of directed mutation even if very minor, in other words "intelligent design" first evolved ~750 million years ago?

It appears some are afraid to discuss this subject in fear that it could become a theory.

My thoughts are that the design was in place before anything evolved/mutated/adapted/altered or changed.

I'd like to hear your ideas
 

Offline Geezer

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Re: How big a role does the epigenome play in evolution?
« Reply #10 on: 24/03/2010 03:37:32 »
Gosh! You must have missed my latest post. Perhaps you would like to reply.
 

Offline norcalclimber

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Re: How big a role does the epigenome play in evolution?
« Reply #11 on: 24/03/2010 05:16:31 »
I certainly do not subscribe to creationism, and I also take a very Copernican view to the Universe.  I look around me though, and I see that life seems to be capable of solving some pretty incredible problems, and very rapidly at that.  Regardless of the specific mechanism behind mutations, we can see that an incredible number of beneficial mutations have in fact occurred, and continue to occur.  We saw the "nylon bug" evolve in a few years at the most, for instance.

Can anybody give me any single, or multiple mutation which would be more beneficial than the ability to pass on environmental experiences to your offspring and "make" whichever mutation needed to happen, happen? 

Obviously any process is far from perfect, or is it?  Really, individual survival doesn't necessarily matter for a species.  The goal is to make the species live forever.  You wouldn't want a whole bunch of mutations which would render the offspring sterile.  Perhaps this is why we have so many species with males/females?  By requiring two different DNA donors, perhaps a beneficial mutation is much more likely if both sexes have received the same environmental input?

I know that "Intelligent Design" was coined by creationists, who then use pseudoscience to defend it.  Lamarckian evolution would probably be a less "loaded" term for it.  But it certainly invokes a response, and to me "life" as a whole, is by far the most intelligent thing I've ever seen.  But I don't think scientists are entirely innocent when it comes to providing incorrect information.  Many science oriented people, can get downright touchy about some subjects which they have deemed unquestionable.  The thing is, sometimes science has been wrong.  Other times, science wasn't so much wrong, as we didn't have the full picture.  The point is, if what you believe to be true is actually true, no amount of logical questioning should ever matter.  In fact, it should always be encouraged, and we should always remember that mathematically, there will always be at least one thing you believe to be true, which is in fact false.

Purely random mutation, IMO, appears to be something which many people seem to hold on to with zeal, as if somehow the whole picture of Darwinian evolution hinges on that one thing.  To me though, I have a hard time reconciling current epigenetic evidence with the idea that somehow life never managed to evolve epigenetics with the ability to "hard" code DNA.  But a parasite evolved which uses three different animals in its life cycle, including a frog which the parasite mutates into a ~15 legged freak so the frog will be eaten by the bird the parasite needs for the next stage. 

Seriously....is complexity really an issue for life? 

Undoubtedly the process of mutation is incredibly dynamic, but with 2000-5000 epigenomic markers per gene, and 22,000 genes in the human genome.... we have somewhere between 44 million and 110 million living switches to play with, in each and every human.  I have no vested interest in directed mutation being true, I simply love learning and thinking.  From what I have learned, logically, I have to think life does have some sort of control over mutation.  If anyone can explain to me how my thinking is illogical, or missing some vital piece of information, please inform me and I will be happy to change my conclusion.
 

Offline Geezer

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Re: How big a role does the epigenome play in evolution?
« Reply #12 on: 24/03/2010 05:49:18 »
I certainly do not subscribe to creationism, and I also take a very Copernican view to the Universe.  I look around me though, and I see that life seems to be capable of solving some pretty incredible problems, and very rapidly at that.  Regardless of the specific mechanism behind mutations, we can see that an incredible number of beneficial mutations have in fact occurred, and continue to occur.  We saw the "nylon bug" evolve in a few years at the most, for instance.

Can anybody give me any single, or multiple mutation which would be more beneficial than the ability to pass on environmental experiences to your offspring and "make" whichever mutation needed to happen, happen? 

Obviously any process is far from perfect, or is it?  Really, individual survival doesn't necessarily matter for a species.  The goal is to make the species live forever.  You wouldn't want a whole bunch of mutations which would render the offspring sterile.  Perhaps this is why we have so many species with males/females?  By requiring two different DNA donors, perhaps a beneficial mutation is much more likely if both sexes have received the same environmental input?

I know that "Intelligent Design" was coined by creationists, who then use pseudoscience to defend it.  Lamarckian evolution would probably be a less "loaded" term for it.  But it certainly invokes a response, and to me "life" as a whole, is by far the most intelligent thing I've ever seen.  But I don't think scientists are entirely innocent when it comes to providing incorrect information.  Many science oriented people, can get downright touchy about some subjects which they have deemed unquestionable.  The thing is, sometimes science has been wrong.  Other times, science wasn't so much wrong, as we didn't have the full picture.  The point is, if what you believe to be true is actually true, no amount of logical questioning should ever matter.  In fact, it should always be encouraged, and we should always remember that mathematically, there will always be at least one thing you believe to be true, which is in fact false.

Purely random mutation, IMO, appears to be something which many people seem to hold on to with zeal, as if somehow the whole picture of Darwinian evolution hinges on that one thing.  To me though, I have a hard time reconciling current epigenetic evidence with the idea that somehow life never managed to evolve epigenetics with the ability to "hard" code DNA.  But a parasite evolved which uses three different animals in its life cycle, including a frog which the parasite mutates into a ~15 legged freak so the frog will be eaten by the bird the parasite needs for the next stage. 

Seriously....is complexity really an issue for life? 

Undoubtedly the process of mutation is incredibly dynamic, but with 2000-5000 epigenomic markers per gene, and 22,000 genes in the human genome.... we have somewhere between 44 million and 110 million living switches to play with, in each and every human.  I have no vested interest in directed mutation being true, I simply love learning and thinking.  From what I have learned, logically, I have to think life does have some sort of control over mutation.  If anyone can explain to me how my thinking is illogical, or missing some vital piece of information, please inform me and I will be happy to change my conclusion.

Good stuff. Can you lay out your theory for us?
 

Offline norcalclimber

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Re: How big a role does the epigenome play in evolution?
« Reply #13 on: 24/03/2010 20:07:45 »

Good stuff. Can you lay out your theory for us?

Theory would be an awfully strong word, hypothesis would be better.  But you pretty much have it already right there in my post.  I'm not really qualified to propose anything as advanced as a full theory.  I just hypothesize that directed mutation via epigenomic markers is probably the primary mechanism responsible for the majority of the life and diversity of life here on Earth.  I also hypothesize that this mechanism probably evolved ~750 million years ago.  But I am definitely not putting forth a new theory, I am asking whether my hypothesis is likely or unlikely based on what is currently known both about the fossil record and epigenetics.  I am also trying to find out if scientists have already come to the same conclusion as I have.
 

Offline JP

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Re: How big a role does the epigenome play in evolution?
« Reply #14 on: 25/03/2010 03:52:44 »
From the brief searching I did (via Google), scientists don't yet have enough evidence to show that epigenetics can lead to permanent traits being adopted by a species.  Until they can show that it's more than a temporary effect lasting a couple of generations, it's a bit extreme to propose that it accounts for the majority of genetic diversity.

Also, to grossly oversimplify it, the way I understood what I read was that if you evolve a gene that can be switched to "on" or "off," epigenetics is basically letting you control whether you choose on or off, but doesn't allow you to modify the gene itself.  In order for you to change the gene, a random mutation is required.  I could be wrong on that, but that's how I understood it at least.
 

Offline norcalclimber

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Re: How big a role does the epigenome play in evolution?
« Reply #15 on: 25/03/2010 04:25:03 »
From the brief searching I did (via Google), scientists don't yet have enough evidence to show that epigenetics can lead to permanent traits being adopted by a species.  Until they can show that it's more than a temporary effect lasting a couple of generations, it's a bit extreme to propose that it accounts for the majority of genetic diversity.

Also, to grossly oversimplify it, the way I understood what I read was that if you evolve a gene that can be switched to "on" or "off," epigenetics is basically letting you control whether you choose on or off, but doesn't allow you to modify the gene itself.  In order for you to change the gene, a random mutation is required.  I could be wrong on that, but that's how I understood it at least.

Why do you feel it is extreme to propose epigenetic directed mutation accounts for the majority of genetic diversity?  Wouldn't natural selection affect epigenomic mutation as well?  Since we know for sure that we have barely scratched the surface on this subject, and it seems a pretty safe assumption that epigenomic markers would also be affected by natural selection; how is it extreme to think it should have developed that ability sometime in the last ~750 million years at least?  On top of all that, it would answer the only kinks left in the theory of evolution.  It would no longer be surprising for an organism to develop mutations which took 2 or 3 mutations before they were even beneficial.  We would no longer have to come up with some way for the rapidity of "random" mutations to change.  While the basics of the theory of evolution is basically proven, there are specifics which have caused us to question some parts of it.  This would answer all those specifics, and still have no intervention from some "higher power".  IMHO.
 

Offline JP

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Re: How big a role does the epigenome play in evolution?
« Reply #16 on: 25/03/2010 04:44:44 »
I think we're disagreeing on a fundamental point: what an epigenetic change actually is.  Is it just a modulation of existing genes/traits or is it the directed mutation of genes to create new traits?  From what I briefly read, the former seems to be the case.  You seem to be saying the latter.  It would be useful if a biologist/geneticist could chime in on this to correct one of us. 

Also, is there any evidence that epigenetic changes are passed down forever?  It would have to be in order to drive evolution, and the reports I read said that scientists haven't been able to observe traits being passed down for more than a few generations.
 

Offline echochartruse

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Re: How big a role does the epigenome play in evolution?
« Reply #17 on: 25/03/2010 23:30:48 »
Why do you feel it is extreme to propose epigenetic directed mutation accounts for the majority of genetic diversity?  Wouldn't natural selection affect epigenomic mutation as well?  Since we know for sure that we have barely scratched the surface on this subject, and it seems a pretty safe assumption that epigenomic markers would also be affected by natural selection; how is it extreme to think it should have developed that ability sometime in the last ~750 million years at least?  On top of all that, it would answer the only kinks left in the theory of evolution.  It would no longer be surprising for an organism to develop mutations which took 2 or 3 mutations before they were even beneficial.  We would no longer have to come up with some way for the rapidity of "random" mutations to change.  While the basics of the theory of evolution is basically proven, there are specifics which have caused us to question some parts of it.  This would answer all those specifics, and still have no intervention from some "higher power".  IMHO.

"Higher Power" what is that exactly?...nature?

Quote from: http://www.time.com/time/health/article/0,8599,1951968,00.html
Darwin taught us that evolutionary changes happen over generations. Bygren and other scientists have evidence suggesting environmental conditions can somehow leave an imprint on the genetic material in eggs and sperm. We have discovered that epigenetics does not alter the genetic code but makes an imprint on genes that is passed from one generation to the next and these can be influenced by environment, lifestyle etc and I would suggest that how long this imprint on genes last would depend on how long these influencing conditions lasts.


Researchers now realize that epigenetics could also help explain why one member of a pair of identical twins can develop bipolar disorder or asthma even though the other is fine. Or why autism strikes boys four times as often as girls. Or why extreme changes in diet over a short term could lead to extreme changes in longevity. In these cases, the genes may be the same, but their patterns of expression have clearly been changed. DNA roll is to carry information.

Baby lotions containing peanut oil is thought to be partly responsible for the rise in peanut allergies. High maternal anxiety during pregnancy is associated with the child's later development of asthma, (isn’t asthma hereditary?) little kids who are kept too clean are at higher risk for eczema. Smoking in their adolescence results in their offspring being a heavier body mass. Taking cocaine can change the way you feel and the way you behave.
Now, a study published in the Jan. 8 issue of Science shows how it also alters the way the genes in your brain operate.

Quote from: http://dnaconsultants.com/_blog/DNA_Consultants_Blog/post/Halloween_Story_Shades_of_Peking_Man/
“We wonder why Western scientists are in such a huff about the conclusions of Chinese paleontologists since there is solid proof of admixture between modern humans and archaic human groups like Neandertals, Homo erectus and Homo floresiensis (the fossils of "hobbits" discovered in Indonesia in 2004). One instance among many of publications demonstrating this possibility is:  Jeffrey D Wall, "Detecting Ancient Admixture and Estimating Demongraphic Parameters in Multiple Human Populations," Molecular Biology and Evolution, vol. 26, no. 8 (August 2009), pp. 1823-27.”



Has it been proven that mixed species can produce offspring that then can reproduce?





« Last Edit: 26/03/2010 00:06:27 by echochartruse »
 

Offline LeeE

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Re: How big a role does the epigenome play in evolution?
« Reply #18 on: 26/03/2010 00:20:54 »
Has it been proven that mixed species can produce offspring that then can reproduce?

This is something that can be neither proved or disproved, for no species has been, or will ever be guaranteed against change.  The 'fact' of whether it has, or hasn't already occurred means nothing in regard to what may happen in the future.
 

Offline echochartruse

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Re: How big a role does the epigenome play in evolution?
« Reply #19 on: 26/03/2010 00:45:11 »
Quote from: http://dnaconsultants.com/_blog/DNA_Consultants_Blog/post/Halloween_Story_Shades_of_Peking_Man/
“We wonder why Western scientists are in such a huff about the conclusions of Chinese paleontologists since there is solid proof of admixture between modern humans and archaic human groups like Neandertals, Homo erectus and Homo floresiensis (the fossils of "hobbits" discovered in Indonesia in 2004). One instance among many of publications demonstrating this possibility is:  Jeffrey D Wall, "Detecting Ancient Admixture and Estimating Demongraphic Parameters in Multiple Human Populations," Molecular Biology and Evolution, vol. 26, no. 8 (August 2009), pp. 1823-27.”


This is something that can be neither proved or disproved, for no species has been, or will ever be guaranteed against change.  The 'fact' of whether it has, or hasn't already occurred means nothing in regard to what may happen in the future.

surely we could stick a couple of species together without partners and try to prove it! why hasn't it been proven? Especially if our past evolution depends on it.

Are Peking Man, Homo Erectus Homo sapiens etc etc all the same species just with epigenetic changes due to location, lifestyle etc?


 

Offline Geezer

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Re: How big a role does the epigenome play in evolution?
« Reply #20 on: 26/03/2010 07:27:13 »
 

Offline norcalclimber

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Re: How big a role does the epigenome play in evolution?
« Reply #21 on: 27/03/2010 18:49:46 »
I think we're disagreeing on a fundamental point: what an epigenetic change actually is.  Is it just a modulation of existing genes/traits or is it the directed mutation of genes to create new traits?  From what I briefly read, the former seems to be the case.  You seem to be saying the latter.  It would be useful if a biologist/geneticist could chime in on this to correct one of us. 

Also, is there any evidence that epigenetic changes are passed down forever?  It would have to be in order to drive evolution, and the reports I read said that scientists haven't been able to observe traits being passed down for more than a few generations.

By definition "epigenetic" changes are not changes to the DNA but rather markers which decide how much or whether to even express a gene at all.  What I want to know, is whether these markers can also choose a mutation at the moment of conception?  So by definition, it would become a genetic mutation at that point, and not an epigenetic mutation; but it was still brought about by epigenomic markers which is my basic point.  It seems highly unlikely to me that life managed to evolve a way to control how DNA is expressed, but couldn't evolve a way to control how DNA is changed.
 

Offline JP

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Re: How big a role does the epigenome play in evolution?
« Reply #22 on: 28/03/2010 03:09:07 »
If evidence points to organisms being able to create actual mutations in that way, then it would be a major deal.  In the articles I read, none of the scientists claimed this was the case. 
 

Offline norcalclimber

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Re: How big a role does the epigenome play in evolution?
« Reply #23 on: 28/03/2010 03:35:13 »
If evidence points to organisms being able to create actual mutations in that way, then it would be a major deal.  In the articles I read, none of the scientists claimed this was the case. 

Nobody claimed that was the case, because we barely know anything about the power of epigenomic markers.  This science is just in its infancy.  What has been proven about epigenetics is that there is more to DNA than just a sequence of bases.  We know now, that large phenotypic changes can be made without changing the DNA sequence whatsoever.

Epigenetics is a major deal.  Scientists may not be claiming right now that epigenomic markers are capable of directing mutation, but that is only because they don't have 50 years of data to back it up.  But just because you don't have 50 years of research, doesn't mean it isn't true. 

When you consider life as a whole, and its incredible abilities to adapt to almost any scenario, and the fact that a mutation which would allow an organism to have any control whatsoever over DNA would be the most beneficial possible mutation ever.  Then you look at the evidence which shows that for 3.5 billion years life barely evolved at all, then all of a sudden.... millions of new species.  Not only that, but those species continued to evolve into millions of new species at an absolute breakneck pace for the next ~750 million years.  And now we know that all of this life can actually control its DNA to at least some extent.  Seriously, are we really going to insist that it is a coincidence?  Is "random mutation" so important to Darwin's theory that the whole thing crashes down without it?  I personally don't think so, I think natural selection is the key to Darwin's theory, and epigenetic driven mutation is extremely complementary to natural selection IMO.

I highly recommend watching "Was Darwin Wrong" by Naked Science.  Pay attention to what they show is actually proven, notice the lack of "random mutation" being mentioned.  Notice how the last few minutes they talk about epigenetics and what they say about evolution and mutation.

When you put all of the information together, and think logically about everything, it seems to me that hanging on to purely random mutation as the driving force behind the diversity of life is akin to insisting the Earth is 10K years old.  This is just my opinion, and maybe after we actually know more than .0001% of what epigenomic markers are capable of we will find out my opinion is wrong.  At the same time, I have yet to see anyone come up with a good reason why I should doubt the ability of life to evolve.
 

Offline JP

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Re: How big a role does the epigenome play in evolution?
« Reply #24 on: 28/03/2010 04:22:53 »
When you put all of the information together, and think logically about everything, it seems to me that hanging on to purely random mutation as the driving force behind the diversity of life is akin to insisting the Earth is 10K years old.  This is just my opinion, and maybe after we actually know more than .0001% of what epigenomic markers are capable of we will find out my opinion is wrong.  At the same time, I have yet to see anyone come up with a good reason why I should doubt the ability of life to evolve.

That's a problem.  It's a hallmark of bad science to say "I believe this because no one has proved it wrong."  Scientific models are accepted because they have evidence to support them. Models don't get accepted simply because no one can prove them wrong. 

I agree epigenetics is intriguing, and should be studied more.  There are places in evolutionary theory that need to be refined, but there don't seem to be sufficient facts yet for scientists to say that epigenetics is the model that answers those questions.  However, if a real biologist is lurking around here who knows more details about this emerging field of study, they could say more about it. 
 

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Re: How big a role does the epigenome play in evolution?
« Reply #24 on: 28/03/2010 04:22:53 »

 

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