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Author Topic: Is evolution really down to random mutation?  (Read 8551 times)

norcalclimber

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Is evolution really down to random mutation?
« on: 14/02/2010 22:06:36 »
So it appears the prevailing theory in macro-evolution, is that random mutations combined with natural selection resulted in all of the diversity of life on Earth.  I have no real problem with this at first, I am not religious in any way, so I have no predetermined bias with regards to the origin of life, at least not in that sense.  I am however highly mathematical, and enjoy high probabilities, so this presents a mild quandary for me due to the low probabilities generated by completely random adaptation.  It seems to me that an organisms ability to adapt to the environment is the most important factor relevant to the survival of a species.  Relying on a roll of the dice for survival doesn't seem to be a very good method, IMHO.  We can look at the species of the planet, and observe that life in general seems to have very little difficulty adapting to survive.  In fact, we can see that if there is even the smallest possibility for an species to survive, it tends to find a way.  So maybe life has found a way to choose mutation?  To the best of my knowledge, we have only scratched the surface of epigenetics, but right away we see that life has at least found some way to control its genes.  Doesn't it make sense that if life found some small way to affect its genes, natural selection would have favored even better control?

In order to attribute the bulk of diversity of life on Earth to random mutation, we must assume life never found a way to control mutation, because any organism capable of choosing mutation for its offspring would be so highly favored by natural selection it would rapidly dominate the environment. 

Imagine you are playing a game, and in this game you are given a coin to start with.  You are told that every time the coin lands on heads you will get another coin.  Every round, you get to use all your coins and every one that lands on heads wins another coin.  This game would be expected to result in you having quite a few coins after not too many flips.  Now imagine another player starts playing, but this player realizes you just have to get the coin to land on heads, you don't have to flip it.  So he just places all his coins on heads, every time.

Obviously player two wins, and wins very quickly, and the same is true if life did manage to find a way to control mutation through epigenetics.  Just a hypothesis, but still a hypothesis which predicts the diversity of life evident on Earth.  Random mutation works to predict this only by using the mathematical easy button which states that even something rare should happen quite a few times over sufficient time scale.


[MOD EDIT - PLEASE TRY TO FORMAT YOUR POST TITLES AS QUESTIONS. THANKS. CHRIS]
« Last Edit: 18/02/2010 16:01:45 by chris »

Madidus_Scientia

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Re: Is evolution really down to random mutation?
« Reply #1 on: 15/02/2010 07:26:06 »
Are you proposing, for example, that a mouse like creature decides life would be better if it could fly and so it somehow starts actively altering its DNA directly toward that end?

My understanding was epigenetics may produce characteristics not dependant on DNA but other environmental factors (different factors cause a different set of genes to be expressed). Whatever the changes are they are not examined by some mystery process and converted into DNA and inserted back into the genome.

norcalclimber

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Re: Is evolution really down to random mutation?
« Reply #2 on: 15/02/2010 07:35:47 »
Nothing so extreme as that, there is no evidence I have seen to suggest anything acting that fast.  Rather that a bacteria which is being starved of a specific protein, could choose to modify an enzyme to be able to metabolize the necessary protein from a different, more abundant source.  Basically still the same evolution we see from current theory, just without a whole bunch of random trial and error first.  We would certainly expect an abundance of life and diversity in a much shorter time scale than should be expected from only trial and error, but it would still be millions of years to develop what we see on Earth.  This also would allow for adjusted rates of mutation, as there would be very little mutation when there was no need.

Madidus_Scientia

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Re: Is evolution really down to random mutation?
« Reply #3 on: 15/02/2010 07:42:39 »
That doesn't really match observation though, mutations appear to be random, and often more likely to be detrimental to survival than complimentary, and evolution seems to have occured over billions of years

norcalclimber

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Re: Is evolution really down to random mutation?
« Reply #4 on: 15/02/2010 08:07:20 »
That doesn't really match observation though, mutations appear to be random, and often more likely to be detrimental to survival than complimentary, and evolution seems to have occured over billions of years

How have we determined that they are random?  Wouldn't that be like trying to prove a negative?

We have proven over and over that mutations occur, and relatively quickly at that.  I haven't found anywhere where someone proved they were completely random though.

What about the extinction events that killed off most life on Earth?  I thought ~90% of the species on Earth went extinct roughly 300 million years ago?  Wouldn't that mean that most of the life on Earth now evolved in millions and not billions of years?

BenV

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Re: Is evolution really down to random mutation?
« Reply #5 on: 15/02/2010 11:52:08 »
That doesn't really match observation though, mutations appear to be random, and often more likely to be detrimental to survival than complimentary, and evolution seems to have occured over billions of years

How have we determined that they are random?  Wouldn't that be like trying to prove a negative?

We have proven over and over that mutations occur, and relatively quickly at that.  I haven't found anywhere where someone proved they were completely random though.

Well, I think it's more a case that no pattern has ever been observed - so the null hypothesis that mutations are random is accepted.

Quote
What about the extinction events that killed off most life on Earth?  I thought ~90% of the species on Earth went extinct roughly 300 million years ago?  Wouldn't that mean that most of the life on Earth now evolved in millions and not billions of years?

Well, it didn't start from scratch - even 10% of species had enough variety to simply re-radiate from there, so modern forms may have evolved in a few hundred million years, but building on billions of years of evolution.

norcalclimber

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Re: Is evolution really down to random mutation?
« Reply #6 on: 15/02/2010 17:58:19 »
Definitely building on billions of years of evolution.  But massive diversity had to show up in just a few million years, and not even a few hundred million, because just over 200 million years after that extinction event, there was another, which killed off the dinosaurs, the vast majority of which had evolved and then went extinct all within a little more than 200 million years.

norcalclimber

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Re: Is evolution really down to random mutation?
« Reply #7 on: 15/02/2010 19:44:32 »
On top of all that, don't many bacteria transmit beneficial mutations through plasmids to others in the local population?  So life has found at least some small way to affect genes(epigenetics) and a way to transmit beneficial mutations to the local population, but it never figured out how to choose the mutations to begin with?

Now I know creationists always try to use the lack of truly gradual mutation fossils as evidence for creation, and I know that actually finding one would be extremely rare, so it's not surprising we haven't found any really good gradual mutation transitional fossils(that I know of).  But isn't that a temporary argument at best?  After enough looking, shouldn't we be able to find at least one example?  How about the possible effects of using the congruency method when classifying fossils?  Could it be that we have mislabeled transitional fossils because we think mutation can't work that fast, so it must be a different species and not transitional?  The biggest problem I see with the congruency method, is that by nature the evidence will agree with the theory, because if it doesn't agree we simply reclassify until it does.  I'm not trying to argue that the congruency method doesn't have it's uses, but isn't that a trap we have to look out for?

LeeE

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Re: Is evolution really down to random mutation?
« Reply #8 on: 17/02/2010 00:35:33 »
Random mutation doesn't need millions of years to be effective: how long it takes is just as random as the nature of the mutation itself.  Although very highly improbable, it is not impossible, just through random chance, that an individual in each successive generation of offspring from a single ancestor could receive a beneficial mutation.

It's also possible that some locations on Earth, due to local radiation hotspots due to radioactive ores or radon seeps, are likely to see higher than normal rates of mutation.  Most of the mutations will still die of course, but statistically, the higher rate of mutations should reduce the time between the occurrence of beneficial mutations (if you're working on the basis of there being a ratio of beneficial/harmful mutations).

I don't think it's realistic to think that a bacteria could "choose to modify an enzyme to be able to metabolize the necessary protein from a different, more abundant source" but an already mutated bacteria might be able to metabolise another protein in addition to the protein it would normally metabolise, or even instead of the normal protein if the normal protein suddenly became scarce.

norcalclimber

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Re: Is evolution really down to random mutation?
« Reply #9 on: 17/02/2010 01:56:36 »
I have a hard time seeing how it isn't realistic to think that an organism might choose to mutate a specific gene, and more and more I'm having a hard time even imagining life not evolving that ability a very long time ago.  Why exactly is that unrealistic?  Because it would be a complex decision process?  Complex is a subjective term.  To us, figuring out what millions of epigenomic markers do is complex, but to each marker it's as simple as yes or no.  I don't see anywhere in life where complexity has been even a remote issue for life as a whole.  I personally feel it's a mistake to think that just because we don't understand how it could be possible, that it must be impossible.  Considering the time scale life has been evolving on Earth; I feel that the only way for the best possible mutation any organism could ever experience(choosing mutation)to not have occurred, would be if it was completely impossible.  Epigenetics, IMHO, could possibly provide the possibility for it.  And if it is even remotely possible, I suggest it must then be considered the likely culprit for millions of new species in just millions of years due to simple mathematics and natural selection.  I know this goes against the grain, and stirs up feelings cultivated by the disagreement between religion and modern biology.  But while I see that the vast majority of the evidence proves evolution, I don't see why completely "random" mutations seem to have been inextricably tied to it. 

Many people seem to think the only two choices are "god" or "random", but why can't the individual have some say in it?


Madidus_Scientia

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Re: Is evolution really down to random mutation?
« Reply #10 on: 17/02/2010 07:00:41 »
Well to test your hypothesis you could examine mutations in a species and see how many are advantageous, neutral, and detrimental. If the organism can choose how it wants to evolve then surely we would find a much higher percentage of beneficial mutations.

That's not what we find though.

Most mutations are neutral. Nachman and Crowell estimate around 3 deleterious mutations out of 175 per generation in humans (2000). Of those that have significant effect, most are harmful, but the fraction which are beneficial is higher than usually though. An experiment with E. coli found that about 1 in 150 newly arising mutations and 1 in 10 functional mutations are beneficial (Perfeito et al. 2007).

Also, I think you're forgetting that a very important factor in evolution is genetic variation. What determines whether a mutation is beneficial or not is the environment. A mutation that is beneficial in one circumstance may be detrimental in another. And the environment is always changing.

Using the example you gave, if all the bacteria somehow analyze this strange new protein they've found, somehow determine what kind of enzyme they need to synthesise to digest it, and then somehow figure out what gene they have to code into themselves in order to produce it, they would all do it, and live happily for a while until all of a sudden the environment changes and this mutation they have becomes detrimental, and they all die off.

In a population with random variation, when this change of environment occurs, some will die, some won't, the species lives on.

Zombie movies illustrate this point in human populations. When the zombie infection/virus whatever spreads all of a sudden it doesn't matter how fancy your clothes are or how expensive your car is, what matters for survival is mostly physical prowess and practical knowledge/wit. The fit labourer with lots of tools to build weapons and defenses is more likely to survive than the rich businessman, even if the labourer was so poorly paid he struggled to survive before the zombie apocalypse. But if you had asked every labourer the day before the infection if he'd like to quit and take a huge sum of money and an expensive car of course he would have chose it. So in the world with some businessmen and some labourers, some survive, some don't. The world full of businessmen is much less likely to survive.
« Last Edit: 17/02/2010 07:19:06 by Madidus_Scientia »

LeeE

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Re: Is evolution really down to random mutation?
« Reply #11 on: 17/02/2010 11:55:47 »
I have a hard time seeing how it isn't realistic to think that an organism might choose to mutate a specific gene, and more and more I'm having a hard time even imagining life not evolving that ability a very long time ago.  Why exactly is that unrealistic?

The short answer It's unrealistic because it doesn't fit with reality.

The longer answer is that there is no mechanism whereby an organism can voluntarily modify its DNA.  For the very first time, I think it's actually possible to prove a negative here, for if we were able to modify our genes then Male Pattern Baldness wouldn't exist: it does, so we can't.  QED.

norcalclimber

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Re: Is evolution really down to random mutation?
« Reply #12 on: 17/02/2010 19:16:18 »
Well to test your hypothesis you could examine mutations in a species and see how many are advantageous, neutral, and detrimental. If the organism can choose how it wants to evolve then surely we would find a much higher percentage of beneficial mutations.

That's not what we find though.

No, to test it you would have to stress the environment first, then look to see how quickly the organism evolved.  No control is perfect, so in a relatively stable environment you would expect most mutations which are observed to be neutral or negative.

http://www.pnas.org/content/88/13/5882.full.pdf
ABSTRACT:  A previous study has demonstrated that
adaptive missense mutations occur in the tip operon of Escherichia
coli. In this study it is shown that, under conditions of
intense selection, a strain carrying missense mutations in both
trpA and trpB reverts to Trp+ 108 times more frequently than
would be expected if the two mutations were the result of
independent events. Comparison of the single mutation rates
with the double mutation rate and information obtained by
sequencing DNA from double revertants show that neither our
classical understanding of spontaneous mutation processes nor
extant models for adaptive mutations can account for all of the
observations. Despite a current lack of mechanistic understanding,
it is clear that adaptive mutations can permit advantageous
phenotypes that require multiple mutations to arise
and that they appear enormously more frequently than would
be expected.


Most mutations are neutral. Nachman and Crowell estimate around 3 deleterious mutations out of 175 per generation in humans (2000). Of those that have significant effect, most are harmful, but the fraction which are beneficial is higher than usually though. An experiment with E. coli found that about 1 in 150 newly arising mutations and 1 in 10 functional mutations are beneficial (Perfeito et al. 2007).

"We measured the genomic mutation rate that generates beneficial mutations and their effects on fitness in Escherichia coli under conditions in which the effect of competition between lineages carrying different beneficial mutations is minimized. "

Sounds to me like they tried to minimize the effects of natural selection, which if I am correct, would naturally result in their result.  I am not saying that E. Coli has some super developed, extremely advanced way to mutate, in fact I would suggest the opposite.  This doesn't mean however, that they do not have any way of recognizing that environmental changes mean they need to evolve somehow.  They would then look for possible beneficial mutations, once found, they would spread it to the entire local population.  Which is exactly what we do see in many other experiments.


Also, I think you're forgetting that a very important factor in evolution is genetic variation. What determines whether a mutation is beneficial or not is the environment. A mutation that is beneficial in one circumstance may be detrimental in another. And the environment is always changing.

Not forgetting it at all, which is why epigenetics can play such a crucial role.  Epigenetics allows an organism to test out a mutation before deciding whether to "hard code" it in the DNA.

Using the example you gave, if all the bacteria somehow analyze this strange new protein they've found, somehow determine what kind of enzyme they need to synthesise to digest it, and then somehow figure out what gene they have to code into themselves in order to produce it, they would all do it, and live happily for a while until all of a sudden the environment changes and this mutation they have becomes detrimental, and they all die off.

You have several assumptions in that statement.  For instance, you assume the new environment would not favor their mutation.  You assume any beneficial mutation chosen, would be bad down the road.  You assume that the organism which chose the initial mutation, couldn't choose another to favor the new environment.  You assume that all mutations, must be permanent changes to the DNA, when epigenetics shows us temporary mutations are possible.

http://www.gate.net/~rwms/EvoMutations.html

Look at #5 on the list:

   " Moreover, tremendous diversity accumulated within each population, such that almost every individual had a different genetic fingerprint after 10,000 generations. As has been often suggested, but not previously shown by experiment, the rates of phenotypic and genomic change were discordant, both across replicate populations and over time within a population. Certain pivotal mutations were shared by all descendants in a population, and these are candidates for beneficial mutations, which are rare and difficult to find. More generally, these data show that the genome is highly dynamic even over a time scale that is, from an evolutionary perspective, very brief."

Papadopoulos, D., Schneider, D., Meier-Eiss, J., Arber, W., Lenski, R. E., Blot, M. (1999). Genomic evolution during a 10,000-generation
experiment with bacteria. Proc. Natl. Acad. Sci. U. S. A. 96: 3807-3812


Zombie movies illustrate this point in human populations. When the zombie infection/virus whatever spreads all of a sudden it doesn't matter how fancy your clothes are or how expensive your car is, what matters for survival is mostly physical prowess and practical knowledge/wit. The fit labourer with lots of tools to build weapons and defenses is more likely to survive than the rich businessman, even if the labourer was so poorly paid he struggled to survive before the zombie apocalypse. But if you had asked every labourer the day before the infection if he'd like to quit and take a huge sum of money and an expensive car of course he would have chose it. So in the world with some businessmen and some labourers, some survive, some don't. The world full of businessmen is much less likely to survive.

With this, you are talking about extremely short term changes, and we know that mutations need to occur in offspring.  Mutations as I suggest, are chosen for the increased survivability of descendants, and the species as a whole.  It only makes sense, that life would have a system like epigenetics, allowing it to make temporary changes.  It also only makes sense that any organism that managed to develop some way to control mutations, would recognize that the environment changes, therefore large changes should be somewhat rare.

I have a hard time seeing how it isn't realistic to think that an organism might choose to mutate a specific gene, and more and more I'm having a hard time even imagining life not evolving that ability a very long time ago.  Why exactly is that unrealistic?

The short answer It's unrealistic because it doesn't fit with reality.

The longer answer is that there is no mechanism whereby an organism can voluntarily modify its DNA.  For the very first time, I think it's actually possible to prove a negative here, for if we were able to modify our genes then Male Pattern Baldness wouldn't exist: it does, so we can't.  QED.

I'm sorry, but all you have said is broad statements which imply we already know everything there is to know about epigenetics.  That is what just doesn't fit with reality.

The problem with your example of male pattern baldness is that it assumes male pattern baldness would be viewed as bad.  That view is subjective, an opinion determined by our conscious minds.  It is quite clear, that epigenetics cares nothing for our conscious opinions, all it cares about is the survivability of the species, and male pattern baldness has nothing to do with that, especially since humans have taken a large degree of normal natural selection out of the picture.

Any ability to influence mutations at all, would be at the cellular level, and I don't know anyone who can tell their individual cells what to do.  However, the cells still seem to know what to do.

If life has no control of genetics, how do organisms with epigenetic mutations know when to revert?  The fact that they do, implies the transfer of information from parent to offspring, information which isn't hard coded to DNA, but is passed on genetically nonetheless.

Any ability to choose mutations to any extent whatsoever, would be so highly favored, that in order to say random mutation is proven to be the force behind the major diversity of life you have to prove that any choosing of any mutation at all is impossible.  To prove that, you have to say we already know everything about genetic mechanisms, and that would be patently false.

Madidus_Scientia

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Re: Is evolution really down to random mutation?
« Reply #13 on: 17/02/2010 20:40:58 »
I'm late for work so i didn't read your whole post, i'll post more later, but where is there evidence for this statement
Quote
Not forgetting it at all, which is why epigenetics can play such a crucial role.  Epigenetics allows an organism to test out a mutation before deciding whether to "hard code" it in the DNA.
?

norcalclimber

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Re: Is evolution really down to random mutation?
« Reply #14 on: 17/02/2010 23:10:49 »
I'm late for work so i didn't read your whole post, i'll post more later, but where is there evidence for this statement
Quote
Not forgetting it at all, which is why epigenetics can play such a crucial role.  Epigenetics allows an organism to test out a mutation before deciding whether to "hard code" it in the DNA.
?

 "When fruit flies were exposed to certain chemicals, 13 generations of their descendants had bristly outgrowths on their eyes - these were not caused by any changes in the DNA, rather the changes were by epigenetic means (Jablonka et al. Transgenerational Epigenetic Inheritance: Prevalence, Mechanisms, and Implications for the Study of Heredity and Evolution. The Quarterly Review of Biology, 2009; 84 (2): 131 DOI: 10.1086/598822)."

Read more: http://www.brighthub.com/science/genetics/articles/35753.aspx#ixzz0fpzZlvFM

Epigenetics allows phenotypic changes to be present for multiple generations without changing the DNA.  This sure seems like "testing it out" to me.

Madidus_Scientia

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Re: Is evolution really down to random mutation?
« Reply #15 on: 18/02/2010 07:40:41 »
Epigenetics allows phenotypic changes to be present for multiple generations without changing the DNA.

It doesn't "test out a mutation before deciding whether to "hard code" it in the DNA."

The genes for the changes are already there, but are just expressed differently in different situations. Here an the example from the wikipedia page:

The best example of epigenetic changes in eukaryotic biology is the process of cellular differentiation. During morphogenesis, totipotent stem cells become the various pluripotent cell lines of the embryo which in turn become fully differentiated cells. In other words, a single fertilized egg cell the zygote changes into the many cell types including neurons, muscle cells, epithelium, blood vessels etc. as it continues to divide. It does so by activating some genes while inhibiting others.[3]

Nothing is re-encoded back into the DNA.

It's like if i'm not sure what the weather will be like outside, so I take with me a jacket, an umbrella, and a pair of sunglasses. If it's cold I use the jacket, raining I use the umbrella, sunny I use the sunglasses, but not the jacket, etc. But I left the house with all of these things to start with, I didn't walk out into the rain, invent an umbrella from scratch, and then take it home with me for next time.

beus34

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Re: Is evolution really down to random mutation?
« Reply #16 on: 18/02/2010 11:08:11 »
What does the 'random' in random mutation really mean?

norcalclimber

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Re: Is evolution really down to random mutation?
« Reply #17 on: 18/02/2010 15:42:32 »
Epigenetics allows phenotypic changes to be present for multiple generations without changing the DNA.

It doesn't "test out a mutation before deciding whether to "hard code" it in the DNA."

The genes for the changes are already there, but are just expressed differently in different situations. Here an the example from the wikipedia page:

The best example of epigenetic changes in eukaryotic biology is the process of cellular differentiation. During morphogenesis, totipotent stem cells become the various pluripotent cell lines of the embryo which in turn become fully differentiated cells. In other words, a single fertilized egg cell the zygote changes into the many cell types including neurons, muscle cells, epithelium, blood vessels etc. as it continues to divide. It does so by activating some genes while inhibiting others.[3]

Nothing is re-encoded back into the DNA.

It's like if i'm not sure what the weather will be like outside, so I take with me a jacket, an umbrella, and a pair of sunglasses. If it's cold I use the jacket, raining I use the umbrella, sunny I use the sunglasses, but not the jacket, etc. But I left the house with all of these things to start with, I didn't walk out into the rain, invent an umbrella from scratch, and then take it home with me for next time.

Epigenome: epi(above) genome(gene), which by very definition means changes outside of DNA.  You assume we know all there is to know about epigenetics though, but the fact is we have no clue whether mutations are driven by epigenomic markers which cause the offspring to have a permanent change to the DNA.  We have barely scratched the surface of epigenetics, but it clearly shows an awareness of the importance of genes to the continued survival of an organism, and this to me is implies a strong likelihood that epigenetics plays a much more important role in the evolution of species than possibly even DNA itself.  We will know much more if we fully map the human epigenome, but that is far far away.

norcalclimber

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Re: Is evolution really down to random mutation?
« Reply #18 on: 18/02/2010 15:49:05 »
What does the 'random' in random mutation really mean?


Actually "random" doesn't even exist in our universe, it is an abstract.  Random means no constraints whatsoever on an event, and everything in the universe operates within specific constraints, which means nothing can actually be "random".

Madidus_Scientia

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Is evolution really down to random mutation?
« Reply #19 on: 19/02/2010 03:05:33 »
Exactly, changes above/over DNA, not to DNA

norcalclimber

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Is evolution really down to random mutation?
« Reply #20 on: 19/02/2010 03:34:35 »
Actually, we have no idea whether they can cause changes to the DNA, that is still up in the air.  What is clear, is that epigenomic markers are what actually controls the DNA, which means it is highly probable that epigenomic markers have a lot to do with all mutations.

Madidus_Scientia

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Is evolution really down to random mutation?
« Reply #21 on: 19/02/2010 03:40:20 »
Exactly, they control the DNA, by switching on some genes, turning off others, but the genes themselves are already there in the DNA.

norcalclimber

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Is evolution really down to random mutation?
« Reply #22 on: 19/02/2010 21:38:32 »
We don't know whether they also cause the development of new metabolic pathways from existing ones.  Every experiment I have so far seen which shows the evolution of a new pathway, it always starts by a simple modification of an existing pathway i.e. producing an enzyme which works only very inefficiently on the abundant food source, but works well on a different food source which is not present.  Normally this enzyme is only produced when the food source it was designed for is present.  The organism mutates to produce the enzyme all the time, then makes the enzyme more efficient for the new food source, then mutates again to only produce the enzyme when the new food source is present.  Considering every gene has thousands of epigenomic markers, it will be a long time before we know for sure if epigenomes are or are not responsible for the diversity of life on Earth.

echochartruse

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Is evolution really down to random mutation?
« Reply #23 on: 28/05/2010 00:59:54 »
What does the 'random' in random mutation really mean?

Actually "random" doesn't even exist in our universe, it is an abstract.  Random means no constraints whatsoever on an event, and everything in the universe operates within specific constraints, which means nothing can actually be "random".

Exactly...

What comes first the cause or the effect? Is mutation/adaptation/change the cause or the effect?

Due to the environment/time the genome networks to produce changes in our genes. So adaptation/mutation/change is the effect.

These changes are brought about by chance such as say, the climate, location, actions, etc.

If you have the chance of living at high altitudes your genome may change to cope with the altitude.

If a random toxin was present your genes would change to cope.

If you are a heavy drinker/smoker your genes may change.

and yes these changes can be inherited.

These changes are not permanent but the effect of actions, environment etc. So mutation is a heavy word, conjuring permanency.

The actual genetic change/mutation is not random.

I have read so much about the genome changing to cope with disease, environment, etc and at no stage was the words 'random mutation' written. Everything could be explained through a process, cause and effect.

change in genome is not the cause but the effect, definately not random.

Does any one understand what I am saying?

« Last Edit: 28/05/2010 01:04:22 by echochartruse »

 

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