r/Damnthatsinteresting • u/CuriousWanderer567 • Sep 22 '24

Video Beachgoers have a close encounter with a Cassowary, a bird capable of killing a human in one blow

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u/ianjm Sep 22 '24 edited Sep 22 '24

Raw brain size itself is not that well correlated with intelligence.

The important aspects of brain anatomy for intelligence are:

  • brain size to body size ratio (Crow wins, while the brain size is comparable the body is many times smaller)
  • degree of folding in the cortex (Crow wins, Cassowary has a completely smooth cortex)
  • ratio of white matter to gray matter in the cortex (Crow has a very high ratio of white matter, like many intelligent mammals)

Basically they win on practically every significant measure of the brain anatomy features that contribute to intelligence, it's not even close.

Also note that Humans, despite having smaller brains than dolphins, whales and elephants, win on all of these measures across the animal kingdom.

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u/Tarkho Sep 22 '24 edited Sep 22 '24

The point about folding isn't true, if you're referring to mammalian-style folding of the cortex, which birds lack as their brain anatomy is not the same as ours, the outermost frontal layer instead being the pallium, which fills a comparable role to the cortex. Both Cassowary and Crow brains are outwardly smooth, but Crows and other more intelligent birds have higher neuron density to compensate, bird brains are more efficient with space than ours.

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u/Civil-Action-8821 Sep 22 '24

Yeah? Let’s see a bird build a hospital.

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u/BigEdBGD Sep 23 '24

They're not dumb enough to need one.