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The baffling intelligence of a single cell: The story of E. coli chemotaxis

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Re: The baffling intelligence of a single cell: The story of E. coli chemotaxis

#121
post #101

Earlier quoted context omitted.

Evolution doesn't produce 1st part of the flagellum, second part of the flagellum, third part of the flagellum. It produces shitty flagellum, better flagellum, good flagellum. But the problem is we don't see the intermediate forms. So right now you might see a complicated flagellum that has a lot of highly specialized parts that all need eachother, but that is merely a refinement that took place after all the pieces…

It seems you may have misunderstood the original argument. The iterative approach suggests increments so minute at each step that they wouldn't significantly impact an organism's survival at any given time. Also given the extremely slow process of evolution and the relatively short number of iterations it is infeasible to suggest such a solution. If a person would like to create an iPhone it's easy to tell them to st…

>so minute at each step that they wouldn't significantly impact an organism's survival at any given time.

That's the thing. Evolution isn't "survival of the fittest" or even "driven by more efficient anything", evolution is simply; if you die before you pass on your genes, you don't pass on your genes. Over long enough time scales, with large enough populations, with tight enough tolerances and strict enough niches, the system roughly approximates a directed iteration of more efficient parts.

Nothing about evolution prevents carrying forward explicitly negative mutations! Nothing about evolution prevents carrying completely unused functionality and features! Nothing about evolution guarantees monotonically increasing fitness!

The giraffe has a certain nerve that goes from it's brain, all the way down around it's aorta, back up it's neck, to it's tongue. It does this, because in the fish we all evolved from, such a detour was less than a centimeter longer than an "optimal" path, and as each next generation went in different directions, it's just not that big a deal. A few hundred extra calories in development, and rare instances of a negative injury outcome are just not going to get fixed, because evolution is almost never vigilant. Most higher level animals have mating behaviors that explicitly favor "wasted" energy, including the long neck of giraffes! Sexual selection has a stronger influence on most animals than evolutionary pressure.

> Also given the extremely slow process of evolution and the relatively short number of iterations it is infeasible to suggest such a solution

This is silly. The vast majority of the ground work for complex life was developed by single celled organisms that produced a new generation every half hour, there were billions of these little creatures experiencing basically any possible mutation all the time, and a water droplet with a billion short lived single cells is exactly the kind of tight tolerance, competitive atmosphere where evolution is most prominent!

Evolution is not iteration. Evolution is pruning bad branches in your breadth first tree based algorithm.

Re: The baffling intelligence of a single cell: The story of E. coli chemotaxis

#122

The way I think about this comes from reading John Holland's "Hidden Order". If you read that book not as a book but as a way to build a Complex Adaptive System, then it comes down to a few essentials. An environment, a bunch of entities, a read/write messaging bus so the entities can interact. The entities need a set of rules and sensors. Put it together and what have you got? Thinking. Or intelligence. Try building…

Sapir-Whorf is bunk

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Re: The baffling intelligence of a single cell: The story of E. coli chemotaxis

#123

Incredible to think how something this intricate with so many interdependent parts and integrated systems could have evolved.

Have you actually seen the results of things made with evolutionary algorithms? They ALWAYS produce "what the fuck, how could this be good" outcomes. From antenna that look like scifi props, to a computational system that somehow requires a supposedly unconnected transistor to be activated, evolutionary systems always find their way to a goal in an unimaginable fashion, because "random" mutations are basically the direct opposite of engineering something, so why does everyone always expect the outcome to look engineered?

Evolution producing a complicated, half non-working, incomprehensible, "everything interacts with everything else in a chaotic and unpredictable to us way", is the EXPECTED outcome.

It's similar to how many big programming projects become spaghetti messes of half integrations and barely functional parts hooked together half-hazardly where every feature relies on a bit of code nobody understands. It's an "iterate on the stuff that works" process, except the machinery inside a cell is way more effective and tolerant of such a regime than our stupidly strict programming languages and computers.

Re: The baffling intelligence of a single cell: The story of E. coli chemotaxis

#124

Earlier quoted context omitted.

I find this to be an incredibly bizarre thing to say. Nobody is stopping you from thinking anything, of course you're allowed and surely you know this very well. I suspect what you're really saying is "Will you still respect me for being a creationist". And the answer is, LOL of course not. Nobody is entitled to have their wacky ideas be respected. A lot of the "free speech" complaints are really demands that other p…

It’s funny, because the creationists generally feel the exact same about evolutionists. Both are faith based responses to questions we cannot answer any other way. Getting caught up in absolutes thinking your interpretation is the gold standard is a sign of an unrefined critical thinking process.

No, evolution is not faith based. If you want something faith based, which creationism purports to resolve, it would be if someone has a strong belief on how abiogenesis actually happened, since that is something that is still not well understood. But, we see evolution happening all around us, all the time.

Re: The baffling intelligence of a single cell: The story of E. coli chemotaxis

#125
post #91

Earlier quoted context omitted.

According to Condorcet's jury theorem, a committee of 10 identical members may be smarter than a single member.

This seems obvious to me, as there'd be ten times more computational resources.

No, it is because the probability of arriving to a correct answer increases when there are more members in the group, but only when the individual probability to arrive to a correct conclusion is higher than 50%. Group of smart people is smarter than an individual. The opposite is true too. If the individual probability is less than 50% then the group of people is dumber than the individual.

Re: The baffling intelligence of a single cell: The story of E. coli chemotaxis

#126
post #65
post #8

Earlier quoted context omitted.

I know. But this is very well understood and researched. All it requires is mutations, time and selection pressure. The Blind Watchmaker is still a good read.

So if a monkeys bangs on keys forever it will eventually produce Shakespeare? I'm quite skeptical

Evolution wasn't evolving towards the specific point we are at now. It was just doing its own thing all the time, with no plans for the future.

So, a better (but still not great) question, would be, if a monkey bangs on keys forever would they ever produce any kind of story at all?

But, that's still not good enough, because evolution is iterative, and would pick out very short stories that worked a bit, and that page kept getting duplicated out to new monkeys who would start typing from the end of that story

Re: The baffling intelligence of a single cell: The story of E. coli chemotaxis

#127
post #106

The way I think about this comes from reading John Holland's "Hidden Order". If you read that book not as a book but as a way to build a Complex Adaptive System, then it comes down to a few essentials. An environment, a bunch of entities, a read/write messaging bus so the entities can interact. The entities need a set of rules and sensors. Put it together and what have you got? Thinking. Or intelligence. Try building…

As can be seen by the specializations between human brain hemispheres. There is a bus between them, but when that communication is cut, and you can see that a lot of what we perceive as a single thought process, is a bunch of independent computing entities with an OS layer on top creating the unity that doesn't really exist.

Just to be clear here, are you talking about the 'left-brain, right-brain' thing? Because I thought that was pretty well debunked.

Also, I think you are talking about the corpus callosum for the 'bus' right?

Re: The baffling intelligence of a single cell: The story of E. coli chemotaxis

#128
post #101

Earlier quoted context omitted.

Evolution doesn't produce 1st part of the flagellum, second part of the flagellum, third part of the flagellum. It produces shitty flagellum, better flagellum, good flagellum. But the problem is we don't see the intermediate forms. So right now you might see a complicated flagellum that has a lot of highly specialized parts that all need eachother, but that is merely a refinement that took place after all the pieces…

It seems you may have misunderstood the original argument. The iterative approach suggests increments so minute at each step that they wouldn't significantly impact an organism's survival at any given time. Also given the extremely slow process of evolution and the relatively short number of iterations it is infeasible to suggest such a solution. If a person would like to create an iPhone it's easy to tell them to st…

No, I understand the argument, it is just built on a false assumption about how the iterations work. That a change is small does not make its effects insignificant. A single codon change could profoundly alter the protein it encodes, and even a small change to a protein or its expression can have a massive effect on the organism. It's not the structures of an orgnaism that mutate, it's the instructions that generate those structures which mutate. Imagine for example a typo on a blueprint - where there was supposed to be a " instead there is a ' and suddenly instead of an 8 inch air vent, now you have an 8 foot door. There is no intermediate step where you have a useless 2 foot hole.

Evolution is not a slow process, it is an irregular process. The odds of a useful mutation popping up at any given time is low, but once it pops up it's there immediately. Yes, an evolutionary process could never make an iphone, but no is claiming that evolution produced the iphone. The complex systems evolution produces are things where all the changes are individually useful.

Re: The baffling intelligence of a single cell: The story of E. coli chemotaxis

#129
post #106

Earlier quoted context omitted.

As can be seen by the specializations between human brain hemispheres. There is a bus between them, but when that communication is cut, and you can see that a lot of what we perceive as a single thought process, is a bunch of independent computing entities with an OS layer on top creating the unity that doesn't really exist.

Just to be clear here, are you talking about the 'left-brain, right-brain' thing? Because I thought that was pretty well debunked. Also, I think you are talking about the corpus callosum for the 'bus' right?

He's probably talking about split brain patients. Here's a video by CGP Grey about them: https://www.youtube.com/watch?v=wfYbgdo8e-8

Re: The baffling intelligence of a single cell: The story of E. coli chemotaxis

#130
post #57
post #50

> I never liked the way biology was taught in high school. It was too much about the names of things. A subject so vast is spoiled by a textbook, which can only point at the endless parade of stuff-there-is-to-know. Amen. You could easily teach quite intricate biology in grade school, if you focused on a fascinating example or two. How many more people would be inspired, rather than bored?

It turns out the curriculum was made by a bunch of teachers that has been old school taught. Seniority and entrenchment, nobody in that group risking their heads to suggest any deviation from old beliefs

Or maybe it wasn't done maliciously -- rather that's the way they thought it should be taught...
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