My understanding is that octopus limbs are semi-autonomous, whereas giraffe legs aren't doing any more decision-making than they are for people or cats.

Which is not to say that I disagree that most people underestimate animal intelligence.

All cephalopods lack myelination in their neural toolkit. What this means is that signal propagation between neurons is between 10-100x slower than, say, a mammal, and it makes signal integration over distance a hard problem.

That evolution has found a way to achieve high relative intelligence against such a strong constraint is endlessly fascinating!

Same with "bird brain" as an insult, meanwhile corvid's display quite a bit of intelligence

It depends on the bird though, doesn't it?

I seem to remember (from one of Konrad Lorenz's books maybe?) that while corvids are extremely smart, some other birds are pretty dumb by human standards... I think some raptors, like eagles and hawks, are very simple-minded. It struck me reading this as a kid because I thought eagles were majestic, how come they aren't also smart? Disclaimer: this may very well be outdated scientific understanding of raptors.

I’ve always wondered if the corvids notice how bird-brained all the other birds are.

Brain folding (not size) is thought to be associated with more efficient cognition.

Cortical layers seem to play a significant factor - wrinkles affect the surface area of the cortex, but layers seem to dictate the level of abstraction a species can comprehend - it's one of the biggest differences between reptiles, mammals, birds, and amphibians. While only mammals have a cortex, in other species, like birds, there are layered structures that can approximate cortical function. Animals that lack a layered cortex or analogous feature, or that have fewer layers in the structure, are demonstrably less intelligent. Birds have an advanced pallum, which is what gives them the edge over reptiles.

The last 4-5 years have been wonderful for neural biology.

Interestingly corvid brains are smooth.

Bees are also surprisingly intelligent, and have absolutely tiny brains.

> surprisingly intelligent

Respectfully, I think this is emergent behavior from large numbers of bees. On their own, they aren't going to run an abacus.

My guess is we overestimate human intelligence.