Really? It is more complicated than the Orca brain? We aren't magic. The differences between our's and the brains of similarly-sized animals are slight. I'd say our brain isn't fundamentally any more complex than an ape's or a dogs. But if you want to compare numbers, Sperm Whales have 18-20lb brains, far larger and more complex than ours by every measurement.
https://en.wikipedia.org/wiki/File:Figure_35_03_05_Brain_siz...
So bacteria? Plankton has a massive impact on the world too. Insects ... the planet is arguably dominated by insects.
Mammalian brains are, plus or minus a few percent, equally as dense/complex. There are aspects of dolphin brains that are far more complex than ours. A dog's brain has far more connections dedicated to smell than ours. There is some evidence that Orca brains have similarly more connections dedicated to emotions. Each brain is tuned slightly differently, ours perhaps more to vision and problem solving, but our biology isn't any more evolved or complicated.