Neanderthals were the superior species and hunted humans into hiding. A global cataclysm occurred, devastating the food supply available to Neanderthals who required more fuel. Humans survived, only barely, because the few who survived on the run had acclimated to living in underground caves.
Sometime in the next few centuries, another cataclysm will occur, wiping out the surface dwelling human species.
Dolphins inherit the earth, and one day look back at the “primitive human species” that clearly gave way to the “superior” dolphin.
The end.
Superior, is good enough adapted to circumstances. Evolution turns your blood into anti-freeze as a inherited sickness, and this bug is a feature near the arctic. For the rest of the planet you are a very sick fish.
Imagine a water-world, with one volcano caldera above water. In that volcano caldera there is a geysir, and th at geysir, keeps a giant diamond ball rolling, since the dawn of time.
Evolution is not a refree, rewarding smartness or excellence. It just a process rewarding even foolish adaptions, in my example, the ability to become flat and squeeze into rift and cracks. It also rewards cultural taboos, like sticking your flatworm head up and wonder at the sky.
So superior, the word, assumes the idea of progress, of going forth towards the end of history, that the process can not crash and get stuck in a million years looping till the sun goes out. And that "getting stuck" is a very real thing, a very real danger, a "reasonable" voice from the gut, to return to reliable roots and thrust your "gut-instincts."