An interesting aside: elephants and whales do still have more neurons than us - African elephants have about twice as many.
But fascinatingly, those neurons aren't evenly distributed, and in fact humans have far more neurons in the cerebral cortex than elephants. Their extra neuron count is almost all in the cerebellum. Primates are skewed towards the forebrain, but elephants are far more cerebellum-heavy than e.g. rodents, which implies that a lot of their extra brainpower is being 'spent' on operating their larger bodies.
By forebrain neuron count, humans are beaten only by pilot whales - and all of the other close contenders are also cetaceans. No one quite seems to know why pilot whales have twice the neocortical neurons humans do, but it's still the number that tracks best with observed intelligence.
But fascinatingly, those neurons aren't evenly distributed, and in fact humans have far more neurons in the cerebral cortex than elephants. Their extra neuron count is almost all in the cerebellum. Primates are skewed towards the forebrain, but elephants are far more cerebellum-heavy than e.g. rodents, which implies that a lot of their extra brainpower is being 'spent' on operating their larger bodies.
By forebrain neuron count, humans are beaten only by pilot whales - and all of the other close contenders are also cetaceans. No one quite seems to know why pilot whales have twice the neocortical neurons humans do, but it's still the number that tracks best with observed intelligence.
http://nautil.us/issue/35/boundaries/the-paradox-of-the-elep...