Pitting Honeybadger

[Riemann]

@EddyTeddyFreddy

Anyone continuing to insist that epigenetic changes are inheritable is either willfully blind or impervious to alteration of initial beliefs.

Just to clarify, although most epigenetic marks are wiped in the germline, there is evidence for the exception, that epigenetic marks can sometimes be inherited - that in certain circumstances the level of gene expression established in a parent in response to the environment (notably environmental stress) can be passed to the next generation via epigenetic modifications to the DNA of germline cells.

Technically, this is a Lamarckian process. That’s why pop science articles (and some researchers) try to hype it. But the thing with biology is that it’s so messy that almost nothing never happens.

So the first question is how much information is really being passed in this way? The answer is very little, there is no evidence that it is important, not much has been demonstrated beyond things like which metabolic pathways are more active. Nothing remotely close to a learned behavior or body morphology being transmitted in a Lamarckian manner.

The other huge caveat is that (as in the linked article below) people researching transgenerational epigenetic inheritance in mammals naturally (as a practical experimental matter) include investigation of epigenetic marks that are not passed via germline DNA modifications but those that are established in the womb. This, of course, does not violate the Darwinian paradigm at all. Changes in gene expression in the fetus established in the womb due to things like maternal malnutrition and stress are certainly inherited, but not in a Lamarckian manner, only in the same way that a child inherits plenty of things (including gene expression) from its parents after birth through sharing their environment.

But you correctly identity the decisive killer blow to any significant Lamarckian evolutionary paradigm mediated by epigenetics. Although epigenetic marks can (rarely) persist for a few generations, they do not have the permanance of DNA, they simply do not last long enough to undermine the Darwinian paradigm for evolution.

Transgenerational epigenetic inheritance

[HoneyBadgerDC]

@Riemann

Although epigenetic marks can (rarely) persist for a few generations, they do not have the permanance of DNA, they simply do not last long enough to undermine the Darwinian

Could they last long enough to influence natural selection?

[Riemann]

@HoneyBadgerDC

Could they last long enough to influence natural selection?

Define natural selection please, so I can be sure you understand what it means before I answer the question. Not a trick, but I’ve defined it for you numerous times, it’s easy to find a primer on basic evolutionary principles online, and I just want to be sure that I’m not (yet again) wasting my time.

If you can’t do that, your question is essentially incoherent, it is just a string of biology-adjacent words.

[HoneyBadgerDC]

@Riemann

Define natural selection please, so I can be sure you understand what it means before I answer the question. Not a trick, but I’ve defined it for you numerous times, and I just want to be sure that I’m not wasting my time.

Any animal that survives long enough to pass on his genes. I will try to give you an example based on my limited understanding which very well might be wrong. Give me a few minutes on this one as I want to create an example that includes possible epigenetics.

[Riemann]

Nope, I just want a straightforward definition of natural selection. There a few valid ones depending on context, any of them are okay. “Any animal that survives long enough to pass on his genes” is not a definition of natural selection.

[HoneyBadgerDC]

@Riemann

“Any animal that survives long enough to pass on his genes” is not a definition of natural selection.

I guess the only thing that I could add to that would be that more successful types might be successful in different ways and gradually branch off into different species.

[Riemann]

So go and reader a primer on basic evolutionary principles, and come back when you can define natural selection. If you can’t do that, how can you ask a meaningful question that includes the term “natural selection”?

[Riemann]

@Sam_Stone

You should probably inform these guys:

A (cynical) summary of this 9-year-old paper is: there are all these epigenetic mechanisms that we know mediate gene expression in somatic cells. Look how much we know about them, and how important they are (in somatic cells). Maybe some of them persist in germline cells and are super important in heredity too.

Here’s a recent thorough discussion of the Missing Heritability Problem, showing that epigenetics is only one half a dozen possible explanations.

Three Legs of the Missing Heritability Problem

[Sam_Stone]

Yeah, and that’s all I said. I was refuting this:

@EddyTeddyFreddy

Anyone continuing to insist that epigenetic changes are inheritable is either willfully blind or impervious to alteration of initial beliefs.

The fact is, it’s an open area of investigation, and categorical statements about epigenetics and heritability one way or another are unwarranted. But there are learned behaviours that appear to be heritable. I’m not a biologist, but my understanding is that auite a few people in the field believe in epigenetic heritability of some traits. Do you disagree?

[Riemann]

@Sam_Stone

But there are learned behaviours that appear to be heritable.

Nothing I’m aware of has been shown that is any other than rare, that would only be called “behavior” under a very loose definition, and at most for a few generations. So not in a manner that has any significance for evolution.

I haven’t read the Wikipedia article on TEI for a while and it has changed a lot, feel free to go through it and find the most compelling experimental examples - they will be there for sure.

[HoneyBadgerDC]

@Riemann

Three Legs of the Missing Heritability Problem - PMC

That was a great article on the subject. I plan to refer back to it often. It mentioned something I was getting ready to bring up that involved the philosophy of the science.

[Ann_Hedonia]

@HoneyBadgerDC

@Cervaise

could

@Cervaise

if you do manage to glean some comprehension out of this and improve your behavior, Christ, it would make the board a better place

You know the post I opened on epigenetics is a good example I think I spent about 150 post just I defending the idea that epigenetics is a valid topic we never got past that that’s as far as it went, if I would have seen a discussion develop on that I would have happily just sat back and watched

But you don’t understand what epigenetics is, dude.

There is virtually no evidence that epigenetic changes are heritable. There is a lot of junk science out there, and some of it misinterprets real studies.

One study that is frequently misinterpreted in that way is the Dutch Hunger Winter study, which was really a study in the effects of starvation on unborn children.

The study found that children whose mothers endured starvation during their pregnancies had worse lifelong health outcomes than their siblings that received sufficient nutrition in the womb. This, to me, is unsurprising.

Some researchers think they have discovered an epigenetic factor which may have contributed to this outcome, a gene that may have been switched off. But there are possible non-epigenetic reasons for this change.

You can read more about it here. This is a gift link.

The Famine Ended 70 Years Ago, but Dutch Genes Still Bear Scars (Published 2018)

This is probably the most frequently cited study with regard to epigenetic changes, and there is absolutely nothing in this story that indicates that epigenetic changes are passed from generation to generation.

There are some relatively small groups of people in the world that have extraordinary skills in a specialized area. For example, there are American Indian tribes that specialize in high steel construction, and members of those tribes frequently have really good balance and no fear of heights.

However, this is not a case of epigenetic changes being passed from generation to generation……the reason is much simpler……members of this tribe teach their children these skills from a very young age.

Most of the ice sculptors that work for cruise lines come from the same small village in Indonesia - but they don’t have special genes that they inherited that give them the skills to turn big blocks of ice into swans and flowers. They just learn these skills at a very young age from their elders.

Sherpas in Tibet do have distinct physical characteristics that have uniquely adapted them to life in cold weather and high altitudes, but that is the result of millennia of plain old natural selection, not epigenetics.

You seem really invested in the idea that people can engage in behaviors that result in epigenetic changes and that they can then pass those changes onto their offspring, but that’s just not how it works.

[HoneyBadgerDC]

@Ann_Hedonia

You seem really invested in the idea that people can engage in behaviors that result in epigenetic changes and that they can then pass those changes onto their offspring, but that’s just not how it works.

I agree that was my original thinking or suspicion. All I was hoping to do here was explore a topic hoping some of the members here with expertise on the subject would mostly carry it along with a few questions here and there from myself and possibly others. So I included things I was hoping to see discussed and then accused of believing things that were false. I really had no opinion.

[Sam_Stone]

I vaguely remember a study on flatworms where they taught a flatworm a behaviour, then ground it up and fed it to another flatfworm, which then picked up the behaviour. Am I misremembering, or was their another cause for that? I thought the theory at the time was that learning the behaviour changed the RNA, and the RNA in the ground up flatworm was passed on or something.

This is way out of my area of knowledge, so maybe I have it wrong.

[crowmanyclouds]

Memory transfer

Memory transfer through memory RNA is not currently a well-accepted explanation and McConnell’s experiments proved to be largely irreproducible.

[Chingon]

@Sam_Stone

This is way out of my area of knowledge, so maybe I have it wrong.

Lol, no shit

[Riemann]

@HoneyBadgerDC

So I included things I was hoping to see discussed and then accused of believing things that were false.

Sorry, was there some ambiguity about this? YOU BELIEVE THINGS THAT ARE FALSE. And that’s only the small fraction of your claims that are coherent. Most of them are not even wrong.

You started at least two threads I can think of based on your pot-induced Lamarckist ideas, people who have actual knowledge of basic biology explained your misconceptions, you completely ignored anything that didn’t fit your preconceptions, and then a few months later you come back recently saying exactly the same thing you started with over again.

If you want to fulfill your grand ambition to be important in the history of human intellectual endeavor, the most useful thing you could do would be to make yourself into a sausage and feed yourself to someone with more functioning neurons.

[HoneyBadgerDC]

@Riemann

If you want to fulfill your grand ambition to be important in the history of human intellectual endeavor, the most useful thing you could do would be to make yourself into a sausage and feed yourself to someone with more functioning neurons

I think you are projecting here.

[thorny_locust]

@Riemann

If you want to fulfill your grand ambition to be important in the history of human intellectual endeavor, the most useful thing you could do would be to make yourself into a sausage and feed yourself to someone with more functioning neurons.

I would like to congratulate you on being inventively nasty in the Pit.

[Riemann]

@crowmanyclouds

Memory transfer through memory RNA is not currently a well-accepted explanation and McConnell’s experiments proved to be largely irreproducible.

But later there was of course this very real discovery in the worm model organism C elegans:

RNA interference - Wikipedia

https://www.nobelprize.org/prizes/medicine/2006/popular-information/