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gwern comments on Humans are not automatically strategic - Less Wrong
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Yes, because brain size does not equal neuron count; there are scaling laws at play, and not in the whales'/elephants' favor. On neurons, whales and elephants are much inferior to humans. Since it's neurons which compute, and not brain volume, the biological aspect is just fine; we would not expect a smaller number of neurons spread over a larger area (so, slower) to be smarter...
See https://pdf.yt/d/aF9jcFwWGn6c6I7O / https://www.dropbox.com/s/f9uc6eai9eaazko/1954-tower.pdf , http://changizi.com/diameter.pdf , http://onlinelibrary.wiley.com/doi/10.1002/ar.20404/full , http://www.pnas.org/content/early/2012/06/19/1201895109.full.pdf , https://en.wikipedia.org/wiki/List_of_animals_by_number_of_neurons#Whole_nervous_system
Cite for the 200b and 100b neuron claims? My understanding too was that H. sapiens is now thought to have more like 86b neurons & the 100b figure was a myth ( http://revistapesquisa.fapesp.br/en/2012/02/23/n%C3%BAmeros-em-revis%C3%A3o-3/ ), which indicates the imprecision even for creatures which are still around and easy to study...
[emphasis added]
Wait, what?
I think jacob_cannell is correct in that whales and elephants have larger brains, but that he's extrapolating incorrectly when he implies through the conjunction that larger brain size == more neurons and more interconnects; so I'm agreeing with the first part, but pointing out why the second does not logically follow and providing cites that density decreases with brain size & known neuron counts are lower than humans.
I don't always take the time to cite refs, but I should have been more clear I was talking about elephant and whale brains as being larger in neuron counts.
"We are probably near some asymptotic limit of brain size. In three very separate lineages - elephant, whale and hominid - brains reached a limit around 200 billion neurons or so and then petered out."
Ever since early tool use and proto-language, scaling up the brain was advantageous for our hominid ancestors, and it in some sense even overscaled, such that we have birthing issues.
For big animals like elephants and whales especially, the costs for larger brains are very low. So the key question is then why aren't their brains bigger? Trillions of neurons would have almost no extra cost for a 100 ton monster like a blue whale, which is already the size of a hippo at birth.
But instead a blue whale just has order 10^11 neurons, just like us or elephants, even though its brain only amounts to a minuscule 0.007% of its mass. The reasonable explanation: there is no advantage to further scaling - perhaps latency? Or more likely, that there are limits of what you can do with one set of largely serial IO interfaces. These are quick theories - I'm not claiming to know why - just that its interesting.