Exploring the worlds of the CORE and out beyond into the Planar Unity, you will find that life is not as abundant as you might think. Although this is a speculative venture into an expansive universe, the realistic tendency of life is that it is in a constant battle to advance before inevitably destroying itself. We see this with ourselves as history loves to repeat itself. However what happens when we do advance far enough to become an interplanetary/interstellar species and find that we are not alone in this universe? This is where speculation comes into fruition!
The Prime Race or species, is considered the main evolutionary path of all intelligent/sentient life. As humans, we are considered sub-race of Prime, and therefore we evolved as a natural course of our planets ecosystem.
When travelling to habitable worlds and scanning for intelligent life, 90% of the time it will be a priminoid species (if they haven't destroyed themselves already).
This does not mean that all aliens are prime and that all prime are the same. Actually, quite the contrary, just as we humans have a diverse species the Prime is incredibly diverse as different worlds allow for evolution to take form in different ways. Some can be generic like us or abnormal relatively speaking, but in the end a naturally evolved, intelligent species is considered a Prime.
So if you are planning on traversing the seven realms of The CORE, the natural path to rebirth will lead you down the Prime path!