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Comment by bitL | Hacker News Reader

Maybe the mutation wasn't really random? I wouldn't be surprised if at some point we find that the "90% unused brain capacity" is actually doing some long-term adaptation computations and then uses various signals to put that information into reproductive cells...

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The "90% unused brain capacity" is a myth.

Furthermore, the brain doesn't control evolution though "thinking", it's powered by natural selection outside the body.

cited by 555 other papers suggesting RNA changes from life experience -https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4333222/

so people are working on reproducing this and understanding this process more, to say more clearly: scientists are actively researching how evolution can happen without natural selection

> how evolution can happen without natural selection

This sounds incoherent. What does "natural selection" mean to you?

Modern usage of “evolution” sometimes conflates “change of the organism over time or a lineage between generations” with “Darwinian selection”. Sexual selection is an easy example of evolution that’s not due to Darwinian “natural” selection.

Sexual selection was one of Darwin's key insights. He realized that the 'fittest' in 'survival of the fittest' was not just about living longer.

https://www.darwinproject.ac.uk/commentary/evolution/sexual-...

Sexual selection is literally a textbook example of natural selection.

"Change of the organism between generations" is called "genetic drift" if it's undirected and "selection" if it's directed. The concept of "evolution without natural selection" doesn't really exist.

Selection is how you get organisms that appear to be designed for a purpose. Sexual attractiveness is a purpose.

Epigenetic research isn't going against evolution, it's refining some details.

We are discovering some nonmendelian dynamics of inheritance, but being epigenetic they are only about how the organism can differentially use its genetic library.

was it not clear that I was talking about OP's claim regarding "natural selection outside of the body" when epigenetic is not outside of the body and can result in changes of the offspring, does your response run counter to my observation?

so far all the responses seem to be more about a semantical distinction of the word evolution and natural selection

Well semantics are important, especially in fields that someone is intimate with, and I'm currently finishing a phd in cis-regulation and epigenetics.

When we stress mice and notice a difference in their offspring through epigenetics, this is something that has already evolved in mice. Parts of the parental DNA get "marked" and the mark passes on to the offspring and influences their development, but the mechanism that connects external stress and the marking of the parental DNA is itself a genetic mechanism and subject to evolution.

The offspring whose development was changed because of the parental stress isn't evolved, much like a baby with FASD[1] isn't "evolved" either

[1]https://en.wikipedia.org/wiki/Fetal_alcohol_spectrum_disorde...

> various signals to put that information into reproductive cells

This idea isn't that far-fetched, when considering something like this is possible https://www.sciencedaily.com/releases/2018/10/181022085844.h...

> "90% unused brain capacity"

However, the myth of the 90% unused brain capacity is a myth. Different parts of the brain are always active depending on the environment and the tasks being undertaken at any given moment, due to the brain's structure as a sort of parallel processing machine with specialized areas (speech, visual processing, auditory processing, etc.).

I don't believe (from what we know currently) that there's any mechanism for the brain to change our genetics, but hey, we may find out someday that it does something like that.

Even if not, I'd be completely unsurprised to find out that some of the "random mistakes" or "junk DNA" that we have floating around in our bodies actually reacts in some obscure way to different environmental influences to tweak our gene expression and whatnot.

Then how do bacteria or plants evolve?

think about what the fish would have to do -- it would have to realize what the problem was, what change would solve it, and then command its body to make that change, all without the benefit of any scientific knowledge. If we could do those sorts of things, we could solve a host of genetic diseases without medical science.

The central problem for Lamarckism is explaining how the body is supposed to know which changes are beneficial. A blacksmith might develop a strong right arm, but also tennis elbow.

We are seeing external adaptive pressures that diminish natural selection as an absolute, such as in this paper https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4333222/

Its nice that science is able to adapt to new information.

Natural selection needed to be an absolute to counter state-religion based spontaneous creation.

But its now not an absolute, with worthwhile investigation of how life experience can make its way into zygotes.

Maybe one day we can even prove spontaneous creation, and learn the process for that.

Maybe one day we can prove there's a teacup orbiting Saturn too !

maybe. the consequences being...?

> We are seeing external adaptive pressures that diminish natural selection as an absolute, such as in this paper https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4333222/

That's still natural selection, it's just a different mechanism for it.

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