>>11329472>there's no one universally accepted intelligence testSure. But regardless, you'd agree that Dolphins are either the smartest non-Ape, or pretty close, right? Which indicates that you can get a lot of brainpower underwater.
And there has only been one crossing of the barrier you mentioned, right? Which doesn't really imply you can't do it underwater, since our observations have a sample size of one, right?
So, at best, this is a purely theoretical argument, and we don't observe this barrier limiting the brain size of aquatic creatures, right?
>In a relatively short period of time human brains sky rocketed in size—we have no definitive proof as to why. Could those same conditions be replicated underwater?I may be incorrect, but isn't the best guess/estimate as to why human brains skyrocketed in size, the ability to use varying food sources, and thus enter widely varying ecological niches? (you kind of alluded to it, with the "cooking" comment)
Humans are native to everywhere from Greenland, to New Zealand, to the Sahara. I don't think that's true for any other large mammal.
Presumably that could be replicated underwater. In fact, it kind of is. Humans catch fish in a bunch of different undersea environments, (and often eat them uncooked, or at least could eat them uncooked).
Plus, I'd imagine there are other ways to get more nutrition out of vegetation, than just fire. Special types of digestion, or other chemical processes, that can operate underwater.
>And without the dexterity of an appendage like human hands?There are some animals with very dexterous appendages that aren't hands. Octopuses, for example, can do a lot of stuff that humans can't.
