
Mathematics Shows How to Ensure Evolution - digital55
https://www.quantamagazine.org/mathematics-shows-how-to-ensure-evolution-20180626/
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alexbeloi
These seems like a interesting model for analyzing which population structures
are most conducive to the spread of memes or ideas. The obvious population
structures are 'highly connected' but this suggests that you can have loosly
structured populations as long as 'have certain features (sic), such as hubs
and self-loops.'

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OnesimusUnbound
Hmm, for an example, in twitter, the popular accounts are one of the strongest
"hubs". Their post can influence many "nodes".

I'm not sure how I can relate "self-loops" in my example.

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sleepyams
Perhaps a self-loop would represent time spent curating one's own profile (or
crafting tweets) as opposed to consuming others?

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rdlecler1
This is not unlike Peter Thiel’s Small-markets strategy. No one cares, you can
monopolize it and then grow at the margin into new markets.

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carapace
One interesting thing about evolution is that meta-evolution is evolution. In
other words, we see "Darwinian" as opposed to "Lamarckian" evolution not
because the latter is impossible, but because there is adaptive advantage to
the former. Gregory Bateson works this out from cybernetic first principles in
one of his books. "Steps to an Ecology of Mind" I think. An evolving system of
either kind will evolve to evince mostly Darwinian evolution.

Another way to understand this is to consider that you cannot distinguish
"Darwinian" vs. "Lamarckian" in the evolution of single-celled microbes.
Microbes don't grow old and die. Each Amoeba is billions of years old. (HeLa
cells are called immortal.[1]) A change in the cytoplasm of an ancestor cell
would be carried into both daughter cells.

In "Selfish Gene" Dawkins works out how death and birth have adaptive value
for genes in multicellular species. The meta-evolutionary "choice" to
reproduce by sex and children (rather than, say, budding, or metamorphosis, or
some kind of mass mitosis) is "made" by the normal process of evolution, not
some additional meta-process.

In short, there is no _a priori_ reason to believe that the life of Earth has
not evolved intelligence. (After all, we are intelligent.) What I mean is, the
machinery of evolution itself will have evolved to be able to direct its own
evolution, _IF_ intelligently self-directed evolution is adaptively valuable.

If you want to prove that Nature is _not_ intelligent you have to show that
there is adaptive value to remaining "dumb". Given what we now know about
adaptive systems, that's the only way Nature would have evolved without
ambient intelligence: if it pays to act dumb.

[1] [https://en.wikipedia.org/wiki/HeLa](https://en.wikipedia.org/wiki/HeLa)

\- - - - -

edit to add: Trawling through the new links I see:
[https://news.ycombinator.com/item?id=17405096](https://news.ycombinator.com/item?id=17405096)

> "Cells Talk and Help One Another via Tiny Tube Networks

Long-overlooked “tunneling nanotubes” and other bridges between cells act as
conduits for sharing RNA, proteins or even whole organelles "

That's teh sort of thing I'm talking about: Life is _one thing_.

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olliej
What are you talking about - no amoeba is billions of treats old, not are hela
cells immortal (the immortality of hela cells is a reference to it being the
first set of human cells that could be reliably grown outside of a human. More
specifically it is Henrietta lacks who is considered immortal).

All unicellular life survives by growing (accumulating enough of the right
chemical components) to replicate its genetic material (RNA or DNA), and then
divide. Errors happen during duplication that provide mutations that natural
selection can work on. In the general act of existing all these organism
accrue broken proteins and waste that they cannot get rid of, these accumulate
in one half of a dividing cell, which eventually results in one half of the
separated cell failing.

In addition to replication errors environmental stresses can also just
directly damage the genetic material which again provides mutations than
selection can be applied to.

So yes we can distinguish between Darwinian selection and Lamarckism, as
Lamarckism is not actually a thing - the evolution of single felled organisms
is purely Darwinian, and can (and has) been extensively studied.

I suspect the misunderstanding here is that meiosis (or is it meitosis? I can
never remember which is which) is only notionally a clone. Once you
acknowledge that one of the two cells after a split is not necessarily
identical to the original you can see a lineage of genetic variation that is
the hallmark of evolution.

This is ignoring lateral gene transfer, but that’s essentially an effect of
gene survival and statistics.

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carapace
> these [broken proteins and waste] accumulate in one half of a dividing cell

I've never heard that before. It seems strange to me because if the cell can
accumulate its trash why not just throw it out? Why spend the energy to
replicate the nucleus for a doomed cell? Can you provide a reference?

In any event, I'm not saying they don't die, I'm saying that every amoeba is a
chemical process that has been unbroken for billions of years. The bag gets
bigger and pinches in twain, over and over again, with nothing like the
discontinuity between mother and child that we have as multicellular
lifeforms.

Every amoeba alive today has been alive since... well the first cell, I guess.

> So yes we can distinguish between Darwinian selection and Lamarckism, as
> Lamarckism is not actually a thing

I'm talking specifically about the level of singled-celled organisms. We can
distinguish between traits that have obvious correlations with DNA sequences,
and traits that do not, but we cannot say with certainty that no cell has ever
acquired a trait that it passed to its descendants _sans_ DNA. In fact,
there's a whole field of "epigenetics" opening up right now:

> Epigenetics is the study of heritable changes in gene function that do not
> involve changes in the DNA sequence.

~
[https://en.wikipedia.org/wiki/Epigenetics](https://en.wikipedia.org/wiki/Epigenetics)

> the evolution of single felled organisms is purely Darwinian, and can (and
> has) been extensively studied.

Sure, "ignoring lateral gene transfer"... I wasn't going to mention that but
it obviously complicates the traditional Darwinian _dogma_ , doesn't it?
You've got bacteria "inheriting" traits from each other!

But anyway, my point is that "the evolution of single-celled organisms [seems]
purely Darwinian" because it _evolved_ that way, not because of some intrinsic
impossibility of Lamarck-ish "transmission of acquired traits".

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olliej
No, lateral gene transfer doesn’t impact Darwinian evolution - genes weren’t a
thing when Darwin published his work - lateral gene transfer does not
complicate evolution, because it isn’t deliberate selection. It is simply a
different matter of gene recombination - sex doesn’t complicate Darwinian
evolution.

Skipped LGT because it required multiple sentences being written on my phone.
It is a misconception that bacteria /decide/ to take up or release plasmids
into the environment. They don’t, it is a simple statistical process. F a
bacteria is in an environment where there is a selective pressure that favors
expressing a given gene (or group)then the bacteria that have those genes
increases its proportional presence in the population pool. Now those bacteria
have become dominant because of a particular set of genes, which means those
genes are being expressed at a significant rate. Expressing the genes requires
duplicating that section of the bacteria’s genome, and moving it of to the
protein build molecules. So now we have an huge (proportional) amount of
floating snippets of genetic material for the useful genes. That structure of
these molecules tends to them wanting to connect their dangling ends, so many
of them do just that (all expressed genes do can end up doing this, it is
simply the selective pressure that increases the rate of expression).

Now as time goes by some of the bacteria will just die, and when their cell
wall collapses any remaining genetic material just ends up floating in the
environment. The most stable are those without dangling ends - the plasmids.
The plasmids can also just escape through the wall generally - there is some
ability for a bacteria to get rid of waste : ion pumps do the work, but
there’s a limit to the size, which is why bacteria cannot simply get rid of
all waste - the net result is that an environment in which a given set of
genes is useful starts to accumulate plasmids that contain those genes.

For absorption of the plasmids, that is simply a product of how bacteria
absorb all materials, so now the plasmid is inside another bacteria. In the
event of any error by the when it cuts the plasmid it can end up including the
plasmid material in its own genome

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carapace
You seem to know what you're talking about, and I appreciate you taking the
time to reply to me, but I'm afraid I don't understand how what you're saying
contradicts what I'm saying. Maybe we're talking past each other. I'm saying
two things:

1\. Meta-evolution happens as part of evolution, there's a logical "strange
loop" there.

2\. We see the kinds of macroscopic evolution among multicellular species that
we do (such as the "choice" of having separate species, or the "choice" of
having death-and-birth) not because it's somehow impossible to be otherwise,
but because these modes of life have meta-evolutionary adaptive advantage.

When I contrast "Darwinian" vs. "Lamarckian" evolution I mean that the former
does not have "inheritance of acquired traits" while the latter does. I might
be using the term "Darwinian" in a non-standard way and I apologize if so.

When I'm talking about not being able to differentiate the two modes or kinds
of evolution in the case of microorganisms, all I'm saying is that there's
_one process_ that has aspects of both modes.

Isn't what you just described about LGT obviously "Lamarckian" in the sense
that a bacteria acquires a trait from "eating" a plasmid, incorporating it
into its own genome, then dividing and passing the trait on to each offspring?
I guess what I'm asking is, what do you mean by Darwinian?

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smrk007
Does anyone know if there is work similar to this being applied to machine
learning? It seems like there could be a lot of potential.

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bdamm
That was my first thought too. Could it be applied to genetic algorithms? And
from my quick review of the article, it seems definitely a yes. Genetic
algorithms are asexual, so that's a check. The competitions just need to occur
in pools with migration between the pools satisfying an amplifier pattern.
Pretty exciting result, and I can't help but wonder if it will find its way
into a number of fields.

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im3w1l
There are both sexual and asexual genetic algorithms and people have
experimented with constrained breeding.

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im3w1l
They way you get rid of cancer is an evolutionary bottleneck. Distill a whole
animal into a single sex cell that is then cloned and cloned again to make a
whole infant. This forces the cell to follow the Categorical Imperative:
however it acts will be universal law.

Heads and that cell is healthy and the healthy cells win. Tails and that cell
has cancer and is stillborn and cancer loses.

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civilian
I think your understanding of cancer is a little flawed. It's not just "the
organism will get cancer" or not, it's horribly complex. Different cancers
develop from different differentiated cells, and often it's a combination of
genetics, environment and chance that causes cancer.

It's awesome that you're thinking about this stuff though. I think you'd get a
lot out of this: [https://www.khanacademy.org/science/high-school-
biology/hs-r...](https://www.khanacademy.org/science/high-school-biology/hs-
reproduction-and-cell-division/hs-the-cell-cycle-and-mitosis/v/cancer)

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im3w1l
The way humanity keeps its DNA clear of cancer over the long term is because
people with cancer die and healthy people don't. A slow evolutionary dynamic
keeping a fast evolutionary dynamic in check. This shouldn't be controversial.

The mechanics of it, is like I said, the population bottleneck. Cancer cells
are parasites and the bottleneck leaves them without a host.

A fascinating cancer is "Devil facial tumour disease". It has learned to
spread from animal to animal, thus bypassing this purifying mechanism. But as
it no longer consists of the animals' own cells it may be argued that it has
become its own species and should no longer be considered a cancer. Supporting
the speciation argument is the fact that the cancer cells even have a
different amount of chromosomes from the animals.

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civilian
But cancer isn't a parasite. It's a flaw in an information system. We have
several gates, oncogenes, that protect us against cancer forming. But then
those genes take damage, then cancer can form.

This isn't a determinist "cancer will form or it won't" situation-- there's a
lot of variance and luck. Furthermore many cancers form later in life, after
people have already reproduced, so natural selection doesn't have that strong
of a hold on it. If cancer worked the way you think it did, don't you think
that cancer would have been naturally eradicated during our evolution?

