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As humans we do things for teleological reasons. Meaning we can say we did X in order to accomplish Y.

Ascribing teleological explanations to evolution is technically wrong, since it doesn’t look ahead.

However, it does something very similar. Our brains process competing options, from plausible to nonsensical, before selecting an action, partly in sequence (ideation), but also in parallel (competition processing).

Evolution tries many options in parallel and sequence too. Just by actually doing them and then selecting which of those choices to keep repeating (better survival), and those to forget (extinction of genes, clusters of genes, or whole species).

So over longer time periods, it acts very teleologically. A kind of reverse teleologic by hindsight.

The same is true for the “brilliance” of this teleology. Evolution tries so many things, that it can solve very difficult problems in very novel ways.

Is that “intelligence”? Our casual usage of intelligence isn’t defined precisely enough to say one way or another.

One person would say evolution is blind, and in the short run it is. But another person might point out that evolution is anything but blind. It is an epic version of Edison’s lab, where millions or billions of false solutions are continually tried and ruled out, to find each new fitness enhancement.

It relentlessly experiments and follows the “data”.

On longer timescales, evolution is effectively teleological, highly creative and very intelligent.

And all three aspects compound over time, just like human learning and research, because evolution doesn’t just find new features, but new abstractions and modularity. Such as flexible reusable gene systems for encoding body parts, epigenetic reuse of features in different kinds of cells for different purposes or triggered and “run” by different conditions, nervous systems, etc.

Thus evolution “learned” to speed itself up over time, letting it more rapidly optimize larger more complex solutions. I.e. orders of magnitude faster creation of new novel animals, than it originally took to optimize the first cellular life, colonies of cells, etc.

Watching evolutions first billion years would not have suggested that the plethora of different intelligent animals, from octopus, parrot to human, would have been remotely possible in the time it took. Evolution’s compounding meta learning created brains, our “true” teleology, and its expansion into technological and economic expressions of the pursuit of survival. All meta extensions of evolution, found by evolution.




There are single proteins that need to "evolve" somehow, but they need to arrive at a very particular shape, and extremely near misses offer no feedback information and are just as good as dead.

But the combinations of amino acid sequences they would have to search through in order to find the correct shape is so large that it is greater by several orders of magnitude than the sum total number of all the organisms that have ever lived on Earth since the beginning of time (which is about 10^40, I think).

So your claim that "evolution just tries so many billions of options, man" just doesn't hold water.

There was a time, back during the 1960s, I'm told, when mathematicians in the academy would openly mock evolutionary biologists for their lack of understanding of statistics. But then political correctness took over or something.


> But the combinations of amino acid sequences they would have to search through in order to find the correct shape is so large

Evolution isn't looking for that sequence.

It is looking for any change in sequence with a positive payoff, and in the meantime constantly diversifying sequences with similar outcomes, creating more opportunities for serendipity.

Every large animal is born with mutations. So we are also quite robust to spreading the search, running multiple experiments at a time, taking small risks with genes not quite as good, which will get weeded out quickly when combined with other weaker genes, but in the meantime cast a wider net for meshing with another gene that complements it.

So yes, in any given species with a nontrivial population, millions or billions of genetic variations are being explored at any point in time. We are nothing like carbon copies of each other, differing by just a couple checkmarks.

This is a radical speed up. Just as sexual recombinatory reproduction is. Evolution today operates with vastly more efficient genetic environment, structures and systems than what early life did.

Tractable statistics do no justice to how biology works and all the paths it searches. I am not knocking formal statistics at all, just noting that past one or two step events, the layered statistics of chemistry, genes, gene clusters, epigenetics, populatoin dynamics of complex creatures in their complex environments, etc. are not going to be tractably modelled.

Measurable sometimes for sure, but not symbolically characterizable or calculatable.


> It is looking for any change in sequence with a positive payoff

The entire reason I used the example of the combination lock was so that hopefully you would understand situations in which "any change in sequence with a positive payoff" is a nonsense concept. You either get the correct combination or don't get any positive payoff whatsoever.

When you are trying "millions or billions" of genetic variations are being explored at any point in time, as you point out, you are off by so many orders of magnitude in terms of the search space that you need to explore that the problem is intractable.

You may as well tell me that you can guess a random password that I come up with because you have a way to test millions or billions of combinations at a time. That's great, but I can come up with a random password that it would take you from now until the end of the universe to guess even if you guess quadrillions of possibilities at a time because I can create a password that would require you to test 10^84 possibilities.


Do you consider that not all possible evolutionary combinations are equally likely?


IIRC, evolution is an optimizer but not intelligent. Some of our expectations of intelligence are actually more lax than people think and include optimizers.


Until we find out that evolutionary steps/genetics are the firings of the neurons of some planet scale brain that thinks using evolution. We do have quite a bit of junk DNA ;)

Almost makes me wanna write a scifi short on it.


That's amazing. Did you just type that out or did you spend a couple of years preparing it just in case?


That's funny. :) I just typed it out in one splat with a few quick edits. But I spend a lot of time trying to get clear and distilled perspectives of everything interesting.




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