All my life, I've heard that all these gigantic dinosaurs that used to live on Earth had peanut-sized brains. I just accepted this as a fact, and I guess it may be a fact.

But now I wonder: why?! If their bodies were so incredibly huge and everything was so big back then, why did the brains not also follow that rule? How is it possible that such big animals (or elephants/whales today) apparently have such small brains?

Why doesn't the size of the body roughly dictate the dimensions of the brain inside? Or do they mean this in a more metaphorical way, such that "small brain" really means "low-capacity brain" rather than it actually being physically small? I would assume that if a brain is big, it automatically features more "raw power" rather than being full of empty, unused space.

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    $\begingroup$ And this was downvoted why exactly? $\endgroup$
    – Z. B.
    Jun 26 '21 at 21:30
  • $\begingroup$ Why not check on the sizes of brains vs. bodies for various big animals today and for various dinosaurs? $\endgroup$
    – Armand
    Jun 27 '21 at 0:10
  • $\begingroup$ Welcome to the site. Your question seems to be unresearched from your side. I recommend you to read this (biology.stackexchange.com/help/how-to-ask) before putting your question on the site. $\endgroup$ Jun 27 '21 at 1:11
  • $\begingroup$ whales and elephants have very large brains. $\endgroup$
    – John
    Jun 27 '21 at 2:11
  • $\begingroup$ It is quite possible that the dinosaurs were very intelligent - we have no way to know it. It is also possible that a few millions years from now, some creature will wonder, how humans, being so intelligent, managed to run down themselves to extinction. $\endgroup$ Jun 27 '21 at 6:53

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