Looking past the tabloid prose, they say they found that selection can occur at the level of the epigenome:
The field of evolutionary biology has seen its share of spirited debates. But if there’s one principle that virtually every expert in the field agrees on, it’s that natural selection occurs at the level of the genome.
But now, a UC San Francisco-led research team has discovered the first conclusive evidence that selection may also occur at the level of the epigenome — a term that refers to an assortment of chemical “annotations” to the genome that determine whether, when and to what extent genes are activated — and has done so for tens of millions of years. This unprecedented finding subverts the widely accepted notion that over geologic timescales, natural selection acts exclusively on variation in the genome sequence itself.
In a study published Jan. 16, 2020 in the journal Cell, the researchers show that Cryptococcus neoformans — a pathogenic yeast that infects people with weakened immune systems and is responsible for about 20 percent of all HIV/AIDS-related deaths — contains a particular epigenetic “mark” on its DNA sequence, which, based on their lab experiments and statistical models, should have disappeared from the species sometime during the age of the dinosaurs.
University of California – San Francisco, “‘Living fossil’ may upend basic tenet of evolutionary theory: Natural selection’s reach extends beyond genome into epigenome, study suggests.” at ScienceDaily (January 16, 2020)
So what becomes of neo-Darwinism if selection isn’t tied to the all-powerful but accidental gene?
Paper. (paywall)
See also: Epigenetic change: Lamarck, wake up, you’re wanted in the conference room!
Darwin spoke of selection he didn’t know anything about genes so why does it matter *where* the selection is occurring?
Oooooooooooh natural selection naturally selected that epigenome work like that, naturally of course, You can extend natural selection into selecting standard particles over antimatter particles to and galaxies over galaxies, natural selection selection everything naturally. It really boils down to if it works it’ll survive!!!!!!! Holy cow novel right!?
Now am I getting this right the conclusive evidence of this is that something that should’ve disappeared tens of millions of years ago is still there and that constitutes that natural selection selected that epigenome to continue to exist?
I will read on for something seems silly about this and it is making a very loud claim
PS I don’t see how this helps anything other than they keep trying to prove that natural selection is the key driver to all things evolution and life has nothing to do with it it has to be naturally selected
So it was an epigenetic response that was passed on for millions of years and help the cell survive, this is their evidence.
I don’t see how this is even a big deal, and I doubt this will survive pier review, in fact it almost seems like the really stretching their claim after reading it.
“based on their lab experiments and statistical models, should have disappeared from the species sometime during the age of the dinosaurs.”
1. Apparently their lab experiments and statistical models didn’t produce accurate results or were misinterpreted?
2. The paper doesn’t say how the genome or the epigenome appeared to begin with. It just seems to indicate that some epigenetic settings were altered and affected the survivability of the given organism?
3. This seems like another case of adaptation associated with adjustments in the system settings?
4. This seems like another example of microevolutionary adaptation. The yeast remained a yeast?
5. No macroevolutionary process seems to be described in this paper?
6. Another example of bacteria remain bacteria, birds remain birds, fish remain fish?
7. What else is new?
AaronS1978,
I know you meant “peer” not “pier” 🙂
Basically the Evo 2.0 $10M prize remains frozen. No winning candidates yet. Not even applying contestants. Let’s keep waiting. Not there yet.
Pw@5:
I think I preferred pier review.
You take the paper to the end of a convenient pier and throw it. The parts that the breeze blows back to you make it into the paper the parts that end up in the water didn’t survive “pier” review.
Darwinists are into random aren’t they? This ought to work real well for them.
here we go again…. the almighty natural selection ….
WHAT IS NATURAL SELECTION ???
Recently i came across a debate at researchgate.net (lots of mainstream scientists there)
It was so funny to see how these mainstream scientists struggle to define the term NATURAL SELECTION :)))))))))))
I would like to share with you, here is a very interesting post (from that debate)
“What is Natural Selection?
Accuracy is important in scientific language, then it is important to know what is natural selection:
Please make your choice from the fourteen options indicated below . To help you taking a decission I may say:
1. Nature does not select.
2. The artificial process by which new varieties (not species) are obtained is not called selection, but breeding.
3. Most of the possibilities indicated below are incompatible with the others
1. A process,
2. A mechanism,
3. A theory,
4. An hypothesis,
5. A scientific law,
6. A natural law,
7. A fact,
8. A truth,
9. A principle,
10. An action,
11. An agent,
12. Survival of the fittest,
13. A semantic ghost,
14. A false expression,…..
Please make your choice…….”
(the full debate is here: https://www.researchgate.net/post/What_is_Natural_Selection#share )
as to:
So natural selection occurs at the level of the genome.”,,,, Really??? That’s an interesting claim and it is a false claim because, After-the-fact differential survival and reproduction of already-living phenotypic organisms (ordinary natural selection) does not explain polynucleotide prescription and coding.
As Abel’s PDF further elucidates,”Biological control requires selection of particular configurable switch-settings to achieve potential function. This occurs largely at the level of nucleotide selection, prior to the realization of any integrated biofunction. ”
As to the fact that,,,
At the 8:15 minute mark of the following video, Dr John Sanford, with the “Princess and the Pea paradox” does a very good job of explaining exactly why Natural Selection is grossly inadequate for explaining the overlapping coding coding that must occur at the polynucleotide level.
Simply put, ‘natural selection,’ in so far as it can be said to operate at all, occurs at the whole organism level, which is far above the level of the 6 billion polynucleotides in the human genome. i.e. The Princess and the Pea paradox!
Thus although “virtually every expert in the field (apparently) agrees that,,, natural selection occurs at the level of the genome.”“, (indeed it must occur at the level of the genome if it has any hope of explaining the multiple layers of overlapping coding within DNA), the fact of the matter is that those supposed experts have no empirical evidence whatsoever that their belief is true.
I agree with the ‘experts’ that In order to adequately explain the coding within DNA, indeed, ‘selection’ must occur at the DNA level. Yet, natural selection is grossly inadequate to explain selection at the level of DNA. The only known cause within the universe that has the power within itself to ‘select’ at the level of DNA, so as to make the thousands, if not millions, of decisions that are necessary in order to produce overlapping coding and information within DNA, is an Intelligent Agent. And an exceedingly intelligent Intelligent Agent at that!
And again, if Darwinian evolution were a normal science instead of basically being a unfalsifiable religion for atheists, this should count as yet another powerful falsification of a ‘basic tenet’ of Darwinian theory.
The problem epigenetics presents to Darwinism is that it demonstrates organisms shaping themselves to the environment somehow, rather than the environment shaping organisms via differential survival rates. So the plan is to zoom out to a lower resolution and declare that that is where natural selection rules. Not a good plan, necessarily, but it is a plan.
Selection acts at the level of the phenotype. The phenotype is the result of the genome and the environment. What we are learning through epigenics research is how the environment and the genome interact to produce the phenotype. The consequence of selection has not been altered. It changes allele frequency. If the epigenetics affect on the gene results in a phenotype that produces more offspring, that gene will increase in the population. If it resulted in a phenotype that produced fewer offspring then that gene would decrease in the population.
@ PW
That’s talk text for you :p
Ed George claims that “The phenotype is the result of the genome and the environment.”
That claim is false. “Many scientists have pointed out that the relationship between the genome and the organism — the genotype-phenotype mapping — cannot be reduced to a genetic program encoded in DNA sequences.
In fact, the reductive materialism of Darwinian evolution is at a complete loss to explain how the biological form of any particular organism may possibly be generated by mutations to DNA:
As Stephen Meyer explains in the following video, ‘you can mutate DNA indefinitely. 80 million years, 100 million years, til the cows come home. It doesn’t matter, because in the best case you are just going to find a new protein some place out there in that vast combinatorial sequence space. You are not, by mutating DNA alone, going to generate higher order structures that are necessary to building a body plan.’
Ed George also claims that, “The consequence of selection has not been altered. It changes allele frequency.”
Yet the claim that selection “changes allele frequency” is found to be negligible to non-existent. And thus Ed George’s claim here to is also found to be, for all intents and purposes, false.
It would nice if Ed George would apologize for his false claims and stopped repeating them. But alas, the lifeblood of Darwinian evolution is deception. It simply can’t survive without it.
.
…and often the avoidance of physical evidence, prediction, and history..
Hey Ed, Sev, an irreducibly complex symbol system was predicted by John von Neumann to be the fundamental material condition of an autonomous open-ended self-replicator. That prediction was later confirmed by experiment (Crick, Watson, Brenner, Zamecnik, Hoagland, Nirenberg, etc), and as it turns out, such symbol systems are uniquely identifiable by their physical embodiment, which was further confirmed by Pattee and others — even being described as a necessary multi-referent language structure required at the origin of Life.. Here is the question for you: Is the gene system an irreducibly complex system of symbols, or not?
@13 Bornagain77:
Let’s examine this gem, atheist evolutionist materialists (not you Bornagain77!) 🙂
– If there is not design
– How can the ‘appearance of design’ exist?
How is it possible to be similar to something that does not exist?
TRUTHFREEDOM asked:
“– If there is not design
– How can the ‘appearance of design’ exist?”
If I see a mirage in the desert that has the appearance of water, how can there not be water?
If I see a large man coming toward me in a dark alley, and I am afraid he will harm me, how can he not harm me?
If I have an opinion about something, how can there be so many people who have a different opinion?
If I am hunting deer and I shoot at a partially obscured shape that sort of reminds me of a deer, how can it not be a deer?
If I see a termite mound that resembles a medieval cathedral, how can it not be a cathedral?
If the Sun is round and yellow, and a grapefruit is round and yellow, how can the Sun not taste like a grapefruit?
Acartia Eddie:
That is the untestable claim, anyway. However there are geneticists and developmental biologists who disagree.
What we have learned via developmental biology is that we do NOT know what determines phenotype. All we know is that genomes and environments influence and control development. But influencing and controlling are not the same as determining.
Assembly lines also influence and control what is being manufactured. But they do not determine it.
Upon investigating the crime scene, I determined that it gives the appearance of a man who was attacked by a gryphon.
Epigenetic changes may contribute to changes in phenotypes with no change to the genotype.
This is a problem for the inference of ancestry and descent.
SA
It is my understanding that epigenetic changes contribute to changes in phenotype with no change to the genotype. There is no “may” involved. Please correct me if I am wrong.
How so? Let’s assume that gene A is expressed as phenotype P1 under environmental condition E1, and as P2 under environmental condition E2. If E1 persists for many generations and P1 imparts increased fitness then the gene frequency will increase in the population. If it has lower fitness then it will decrease.
I think that it is reasonable to predict that if one of the phenotypic expressions was deleterious and the environmental conditions were such that this phenotypic expression was present for many successive generations, that the frequency of this gene might dramatically decline or even disappear. It would be interesting to see if this is the case.
Acartia Eddie:
From Wikipedia on genotype:
DNA methylation is an epigenetic mechanism that can modify the function of genes and affect gene expression. That, in turn, determines one (or more) characteristics.
Ed George
I wasn’t clear on that. I meant epigenetic influences or factors may cause changes to the phenotype.
I think the problem would be if E1 was present at one time, but then was lost somewhere in the history of the organism. As such, we cannot trace it. If changes in the phenotype are independent of DNA sequences, then we can’t use sequence similarity alone to make accurate inferences about ancestry. We would have to know what kind of epigenetic factors were at work and what effect they had on gene expression over the development of the organism.
It makes the idea that evolutionary theory could actually predict the development of a species, or even give a step-by-step gradual picture of the development in the past, even more impossible.
Epigenetic factors which can change the phenotype, add another random variable to evolution..
It cannot be as simple as claiming that a new feature emerged because a species had to move geographically or find new food sources or face competition.
SA
Yes, that is my understanding as well.
But they aren’t independent of DNA sequences. They are just different expressions of the same gene. If the expression changes because the environment changes, the new expression must be either neutral, beneficial or slightly deleterious for it to survive long term. Comparison of the genome over time would still be a good indication of ancestry.
And a source of heritable variation is a requirement of evolution.
EG
That could be the case, I’m actually not sure how it would work.
I was considering a scenario where an epigenetic factor emerged in the history of an organism, causing variation in gene expressions and then the development of new features. Then the factor was lost for various reasons, unknown to us today.
I think this paper indicates that the researchers are struggling to understand the history of methylation in this organism over time, from what they would have expected (it would be randomly lost in 130 years) and what they eventually found.
The selective advantage they assigned to it was in the prevention of transposons, which would end up limiting changes to the genome (and restricting the potential for beneficial mutations).
My key point is that it adds another random variable, making it more difficult to trace lineage. But I haven’t studied this closely enough to know either way what it really means. Epigenetic signals could simply be treated like any other environmental factor, I suppose. Not sure about that.
How? I honestly don’t see what point you are trying to make.
Neoteny- The Axolotl, is an organism that was once thought to be two different species. Without environmental iodine it never completes its metamorphosis. Yet it reaches sexual maturity and can reproduce before that major change.
Sure… but SA says
DNA sequence makes in clear the neotenic Axolotl are not distinct from the metamorphosing ones.
@16 Pater Kimbridge
Pater Kimbridge replied:
Appearance is a relational concept. Something is an ‘appearance’ when it has a real counterpart (desert mirage= appearance / real water= real).
According to Evolution, design is an ‘appearance’.
If there is ‘appearance’ of design, it is because there is real design.
We know design is real, and we know it because we humans design things.
If design is real — materialism is false (materialism states that design is an illusion).
Design is real — materialism is false.
Materialism is false.
Mimus
Ancestry will be assumed because of sequence similarity (although I assume common design from the creation of life) but the question would be how closely related the organisms are and how they diverged. Confusion about ancestry seems to be only one of the problems with the inclusion of epigenetic mechanisms into evolutionary explanations though. In this case, similar DNA can show different morphology. So, estimating how similar various organisms are based on DNA similarity alone would give inaccurate results. In two organisms with similar DNA sequencing, if epigenetic factors were present at some point in history for one and then lost, then new features developed in that one and not in the other. How does that get traced?
But that’s only one problem and I can see how it would be dismissed simply under the assumption that sequence similarity necessarily means descent by modification. A bigger problem arises when projecting backwards (which, instead of predictions forward seems to be all that evolutionary theory can do), there at least four variables to contend with:
Random mutations, Random external environmental effects (food supply, competitors, weather, etc) random epigenetic factors and non-random selection for fitness.
How does the addition of another random factor that may or may not be selected for and cannot be found in the historical record, affect whatever evolutionary predictions or explanations that can be made? There is some attempt to calculate the effect of negative mutations to DNA sequences but what about the negative effect of epigenetic factors?
In this case, the researchers do not know the effect of various epigenetic mechanisms on the development of other species.
So again, the theory supposedly explains relatedness on the basis of sequence similarity but whether morphological changes occur because of mutations to DNA or because of random epigenetic mechanisms is unknown. I would think this should tell us something about the “certainty” of evolutionary claims prior to this new awareness (of the selectability of epigenetics) but I will guess that the very same people who claimed that epigenetics had virtually no impact at all on the development of organisms and that all changes were based in changes to DNA sequencing alone, will have no problem with findings that “upend” that notion.
This is really pretty garbled, but you seem to be confusing ancestry and phenotypic similarity.
DNA sequences will tell us how closely related species are, and I don’t see how epigenetics (as in DNA methylation) changses. It’s true that DNA sequence alone can map directly to phenotype, but that’s basic 1930s quantitative genetics (invented by Fisher and other evolutionary biologists) and nothing in DNA methylation alters this.
Mimus:
That is far from true. When the human genome was mapped the scientists didn’t find anything that linked the genome to “humanness”. It is true the DNA controls and influences development. But that is about it.
I think it’s fairly obvious from context that there’s a typo there, read it as “cannot” (or cannot always) map directly.
That’s some typo… 😉
Mimus
Of course not. “We knew about this for a long time.” The Theory predicted it. I think Darwin knew about it, if I’m not mistaken.
Darwin didn’t know about genes, let alone DNA methylation. Selection of epialleles goes back at least to 2002 (https://doi.org/10.1016/S1369-5266(02)00233-9), can happily be modelled by extensions to standard pop-gen models (https://doi.org/10.1016/j.tpb.2011.08.001).
Even if it turns out a lot of traits are the result of selectoin acting on hertibale variation in epigenetics and not hertibale variation in genetics, I’m not sure it would matter a great deal?
Natural selection is a process of elimination. It doesn’t “act” on anything.
@36 ET
There is some dude out there saying “we are always hallucinating”. (Bornagain77, could you please remember us who is that person? You have lots of amazing information and quotes).
Maybe “Natural Selection” is an hallucination? Were not we designed to see patterns where there are none?
Mimus
I don’t know but I would think at least it would require new models and projections, given that the impact of DNA sequencing itself on phenotype would have been overstated.
But I’ve learned that the safest guess in these matters is that no matter what we find, it’s not going to be considered that significant.
I had a discussion with Bob O’H last week on that topic. He felt that no matter what new function we might find for non-coding DNA regions that it wouldn’t have much significance overall.
The science media tries to sell it as something big. Probably the researchers who make discoveries want it to be important. But for biology in general, it doesn’t seem to register.
I’d imagine that there could be some surprising influences from epigenetic factors and if, for example, we discovered that non-observable environmental pressures (stress, climate) caused changes in gene expression and then those changes were heritable (I’m just hypothesizing) that would mean something more. It’s sort of like a learned behavior that is somehow transmitted.
Is that true? Possible? I don’t know. Those researchers claim it, but it’s hard to assess.
But if true, would it mean that virtually invisible, disappeared, factors changed DNA expression from deep history and we’d have no way to discover or trace it?
Again, I don’t know – I’m just speculating and attempting to understand more.
transgenerational epigentic inheritence is possible. It seems to be extremely rare in mammals and (relatively) common in plants. But your questions highlight the porblem for people that want to use this to overthrow mainstream evolutoinary biology.
If epigenetic changes are rapid and turnover quickly then they are only noise over evolutionary time-scales, switching back and forth rapidly.
If they are stable over many generations then we are back to have a source of heritable information which contributes (or doesn’t) to an organisms reporductive sucess. So out ordinary popgen models (with slight modificatoins for epi-mutations) are in play.
It’s true that we couldn’t find the genetic variants responsible for a gene-expression trait that was inherited epigenetically. But we can survey histone and DNA modificatoins with sequencing technology too. We might not be abel to learn precisely what caused the initial production of the epi-allele (but note in the case of the OP we do), but that doesn’t seem like a big problem to me.
Again, I do think the paper in the OP is really interesting. It’s quite a suprise to me that epigenetic modificatoins can be maintained for so long by natural selection, and it’s good evidence for how damagin TEs can be.