Our unique brains have made it possible for us to cooperate in groups in ways that are impossible for all non-human species.
Our consciousness is unique but not our brains. Dolphins and whales have much more massive and sophisticated brains than humans.
If consciousness is a by-product of brain, dolphins would have super consciousness.
Why dolphins don't have at least a similar human intelligence?
They are totally isolated from humans too. They could developed intelligence without human competition.
How do you explain that?