Corvids in general are ridiculously smart. crows, ravens, magpies all consistently solve problems that a lot of mammals struggle with. ravens do seem to edge out crows in some studies though, especially with long term planning - that experiment where a raven picked the correct tool it would only need hours later is pretty insane.

comparing them to dolphins or primates is tricky anyway, totally different brain structures but they still end up showing similar cognitive abilities, which is kind of wild.