39 Comments

Hey. I'm not an expert in physics or anything but I was wondering, do you think the same principles could be used to construct giant trees? I know the height of trees is limited by physics and the way they pump water up to the top. What would plants look like with better pumps?

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I never claimed that they were the same category - what I said was that culture is part of biology. Without biology there is no culture. Rocks and stars are examples of things that are not part of biology. Culture is not like that - it is part of living systems.

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The rendering of a hypothetical assembler with one-fourth power (Z = 4) scaling law looks a lot like biological systems with "plumbing": http://www.molecularassembl...

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I wonder how dinosaur's circulation system worked. Did it scale the same way?

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They could have the same meta-cancer solution that whales apparently do.

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I don't think culture is part biology any more than software is part hardware. They are hugely interrelated, but they're clearly two separate categories.

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The last incomplete exposition about "thermodynamically reversible machinery to rearrange molecules" reminded me of a 2014 article called "Statistical physics of self-replication" which suggested that bacteria operate near the thermodynamical limit of replication:http://www.englandlab.com/u...

And this together with the congestion idea suggests that energy transfer in biological (and possibly technical systems) may be limited to that scaling law.

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Yes, but it doesn't need to be the sun. In general energy sources including food sources need to be transferred and metabolized. That would imply that food chains could also fit into this pattern. It would be interesting to look into the metabolism and growth rates of societies of life forms like ants, packs/herds and in the large human societies if different sizes.One prediction would be that a larger society grows slower.

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Kind of the polar opposite of (pick your favorite nemesis group), but with a similar outcome.

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I wouldn't count them as wheels for the purposes of this discussion because I don't think the chemical mechanism can ever scale to macro-sized wheels; if they can't, then there's no question of evolution doing it or not.

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Do bacterial flagella count as wheels?

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I agree the pump cycle explanation doesn't seem to work for plants. But sunlight congestion seems a pretty general density dependence explanation.

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Bio systems need to move food/oxygen from single points of entry to each cell, and waste to points of exit.

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I don't buy your explanation with pump and sun. If the relationship depended on particular mechanisms the plot would look much different in different areas and domains but it doesn't. For example plants don't use cyclic pumps but rather continuous transfer. To me it looks like there is a deeper shared relationship. One idea that comes to mind is one of organizational complexity where more complex life forms build on smaller ones.

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That analysis is of a very different method of assembly than used by biological systems. Bio systems seem to expand in place, and so don't need delays to move sub-assemblies to the location where assembly happens. Bio systems construction times seem instead limited by metabolism.

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