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Why birds do not fall while sleeping

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Re: Why birds do not fall while sleeping

#51

"The mechanism’s passive character is surprising" Are they saying that birds are in a stable equilibrium while standing? I always assumed that some low level activity in the Cerebellum would actively stabilize them even during sleep. If this is not the case, a dead parrot should be perfectly able to stand, right?

[deleted]

Re: Why birds do not fall while sleeping

#52
post #30

Earlier quoted context omitted.

Using your analogy, it's absolutely unknowable to bacteria, and therefore absolutely unknowable to us. Random is perhaps the most intellectually honest way of describing it, since it is widely accepted that randomness is a feature of relatively uncomplicated systems.

What is called as 'Random', I will term it as 'free will'. In case of a human training an AI, free will be of the human and in case of creation of universe free will be that of the 'intelligent designer'

at least for human it is definitely not 'free will' as it is influenced by everything that has happened to it before and would not have made the same choices, if it had been influenced by other things in another way.

Re: Why birds do not fall while sleeping

#53

When I was younger, I was fascinated by evolution, especially the intricacies of how things just work. This fascination also explains why many people believe in the intelligent design theory. However, witnessing the rapid evolution of AI with just a few hundred GPUs, enough data, and power, I no longer wonder what a billion years of feedback loops and randomness can achieve.

AI isn’t being trained on random though. It’s the corpus of a large portion of all of humanity’s written communication. I don’t think it’s a good analogy to evolution. A single training session will iterate more than the number of generations of all birds.

> A single training session will iterate more than the number of generations of all birds.

But that's not the right analogy. Evolution happens at the individual level, and even to some extent at the individual gamete level. So it's actually every single fecundated bird egg that ever existed, and even every single spermatozoon and egg cell every time two birds mated. Not to mention every division of every bacterial cell in every bird gut, since microflora are a key part of the organism too.

And even this is an undercount, since the DNA and gene expression of an individual actually changes during its lifetime, and those changes can be passed down to offspring through various mechanisms. So there is a constant process of evolution that even all cells inside a living organism go through, that we're still trying to fully understand.

Re: Why birds do not fall while sleeping

#54
post #39

When I was younger, I was fascinated by evolution, especially the intricacies of how things just work. This fascination also explains why many people believe in the intelligent design theory. However, witnessing the rapid evolution of AI with just a few hundred GPUs, enough data, and power, I no longer wonder what a billion years of feedback loops and randomness can achieve.

Where's randomness? AI is an intelligently designed algorithm trained to mimic words of highly intelligent species, and all that runs on GPUs that didn't evolve from a pile of mud, but were intelligently created according to a plan.

The commenter is wrong. There is not a single analogy between the development of AI and evolution.

Re: Why birds do not fall while sleeping

#55

Earlier quoted context omitted.

AFAIK key insight into evolution is not randomness but rather sheer amount of compute. Specifically, evolution is a massively parallel flood algorithm that will try every single mutation. Barely any of them will have positive impact on organism fitness, but some will.

The way I understood evolution wasn't that "some mutations will have a positive impact", it's more like, when a species hits hard times, "some mutations allow it to survive long enough to reproduce". Sure, you have dominant genes like eye colour. But evolutionary changes to a whole species are more about weeding out genes that cannot survive, right? Because if a species has no specific sexual selectors for breeding a…

You will probably find this article about the species concept interesting:

https://plato.stanford.edu/entries/species/

Re: Why birds do not fall while sleeping

#56
post #47

"The mechanism’s passive character is surprising" Are they saying that birds are in a stable equilibrium while standing? I always assumed that some low level activity in the Cerebellum would actively stabilize them even during sleep. If this is not the case, a dead parrot should be perfectly able to stand, right?

Only if it's a Norwegian Blue, as far as I know.

Though in that particular case it may in fact be the nails in its feet causing the phenomenon.

Re: Why birds do not fall while sleeping

#57

Earlier quoted context omitted.

AI isn’t being trained on random though. It’s the corpus of a large portion of all of humanity’s written communication. I don’t think it’s a good analogy to evolution. A single training session will iterate more than the number of generations of all birds.

> A single training session will iterate more than the number of generations of all birds. But that's not the right analogy. Evolution happens at the individual level, and even to some extent at the individual gamete level. So it's actually every single fecundated bird egg that ever existed, and even every single spermatozoon and egg cell every time two birds mated. Not to mention every division of every bacterial ce…

> since the DNA and gene expression of an individual actually changes during its lifetime, and those changes can be passed down to offspring through various mechanisms.

That statements need a whole lot of backing. It contradicts the Central dogma of molecular biology [0]. The idea that an organism can pass on to its offspring physical characteristics that the parent organism acquired through use or disuse during its lifetime is called Lamarckism which was disproven more than a hundred years ago.

[0] https://en.wikipedia.org/wiki/Central_dogma_of_molecular_bio...

Re: Why birds do not fall while sleeping

#58
post #47

"The mechanism’s passive character is surprising" Are they saying that birds are in a stable equilibrium while standing? I always assumed that some low level activity in the Cerebellum would actively stabilize them even during sleep. If this is not the case, a dead parrot should be perfectly able to stand, right?

Only if it's a Norwegian Blue, as far as I know.

Lovely plumage

Re: Why birds do not fall while sleeping

#59

When I was younger, I was fascinated by evolution, especially the intricacies of how things just work. This fascination also explains why many people believe in the intelligent design theory. However, witnessing the rapid evolution of AI with just a few hundred GPUs, enough data, and power, I no longer wonder what a billion years of feedback loops and randomness can achieve.

AI gets backpropagation whereas evolution is more like particle swarm optimization (pick a bunch of random values, then pick more random values near the ones that do best). Backpropagation is way better/faster since in expectation the gradient points toward a better set of weights, but it relies on a differentiable loss function.

Re: Why birds do not fall while sleeping

#60
post #20

When I read "tensegrity" I thought of these strange tables/scupltures you can buy: https://www.amazon.com/s?k=tensegrity

A good example are bicycle wheels made with ropes but if you think of it even of steel spokes as a single spoke by itself cannot maintain the structure and it all comes together when the spokes are tensionned. https://berdspokes.com/collections/berd-wheels

Obviously a wheel is the easiest design you can build based on tension given its symmetric nature.

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