Isn't it interesting that ONLY humans seem to be blessed (cursed?) with a SPECIAL kind of intelligence? I don't doubt that Orcas and Dolphins are equally as intelligent, but they lack something critical to humans - the desire for MORE. We are constantly in need of the next thing, the biggest thing, the peak of possibility. They seem content just being and existing. More power to them!
And a lifetime of structured learning. Let's compare intelligence to a feral human with no schooling and raised by other humans with no schooling. I imagine it'd be closer than we think.