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0 pointscycomanic2y ago0 comments

> There are many phenotypes in the living world which have evolved but for which there is no reason to believe that the phenotype is either (a) supremely efficient and/or (b) under selection pressure (the two are obviously related).

> Evolution has no tautology. Brains do not evolve to be supremely efficient, just like humans do not evolve to be supremely efficient.

> What exists today is that which has survived, for whatever reason. It's not even possible to say something as apparently simplistic as "the only purpose evolution respects is leaving behind more copies" because that ignores (a) group selection (b) changing ecosystems that favor plasticity in the long run.

A primary example of this are our legs, they would be much more efficient if the knees pointed backwards. They are not the most efficient design, but simply good enough.

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m-i-l2y ago

> "our legs, they would be much more efficient if the knees pointed backwards. They are not the most efficient design, but simply good enough."

I don't think you can say one leg type is better than another without reference to the intended use of the leg - plantigrade legs have better "stability and weight-bearing ability"[0], whereas digitigrade legs (like those of cats and most birds, which BTW appear to have a reverse knee but don't because it is the ankle working like a second backwards knee) "move more quickly and quietly"[1].

Tying this back to the original point, the same is true for brains and computers - they are each better in very specialist cases within specific constraints.

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

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

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