11 Comments

One might expect metabolic rate to scale with the 2/3 power. The larger exponent may reflect effects of circulation and breathing

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Was not aware of the law at all! But I do often tease my wife about her low resting heart rate, which according to our Fitbits is about 10 BPM lower than mine. Turns out the joke's on me, and I'll die sooner having used up my heartbeats prematurely!

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There's never been a better time to do more yoga.

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Ugh. Conscious breathing and holding a pose for entire minutes at a time? Hard pass! I'd rather...*dies*

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When you zoom in on a specific species, Kleiber's Law loses its grasp.

https://www.psychologytoday.com/us/blog/canine-corner/201701/why-do-large-dogs-have-shorter-life-spans-small-dogs

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Excellent point (and one I'm already very familiar with, about dogs in particular). Does selective breeding play the key role here?

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That would be my guess. Over emphasizing one trait creates emergent effects.

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There we go again, muddying up the data pool!

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Some creatures get a boost: while Kleiber Law is a rough and general rule there are exceptions.

Kleiber's Law: https://en.wikipedia.org/wiki/Kleiber%27s_law

There is the brain-body mass ratio for example: https://en.wikipedia.org/wiki/Brain%E2%80%93body_mass_ratio

On the other hand, in Economics, the curve reaches zero points at the limits. so if there isn't enough trade then the level of scale does not reach one because there isn't enough volume and similarly if trade is too fast then the object blow up, for example currency. ( the Argentinians for example had inflation over 100% and are willing to try just about anything including blowing up the Peso)

In short, there are limits in any given field to the scale principle. I really ought to write an essay covering this because it actually is important. Think of it as the 201 to the 101.

In the 301 one has to get back to actual research. e.g. jstor.

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Pick the torch up and write that essay! I love when something I write encourages someone else to pull that writing trigger, even (maybe especially) when you're already familiar with the concept, but have something to add.

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Really there is an entire book. what defines the "sweet spot" for a given enterprise is where the mass/ratio stays stable, and when one gets out of that sweet spot, either too high or too low, there has to be a good reason to go farther.

An example would be the Cray supercomputers, the Cray used to GaAs chips to get the extra boost of performance, but it was highly expensive and therefore there had to be some good reason to do that. Otherwise Si was enough.

There is a complete book on where the sweet spots are for a variety of systems. and I will get to that when I have finished several other books on a variety of other topics. right now I am explaining to people why 1. there were three eras of thought that can be defined as modern. (Victorian, Modern, Postmodern) 2. Why the postmodern is changing to a new age which I call Digitality. (Inputs) 3. What will be different in the coming age. (Outputs)

The summary is in Modernism, Postmodernism, and Digitality from which the book will be expanded.

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