The colonists on board The Habria found themselves cut off from all their sister ships and alone in space. As they reached the last of their supplies, they found a habitable planet.
Unfortunately, the planet was already inhabited. The native population was humanoid, but primitive. They had a life span of only about ten years. Humans settled on only one continent in an attempt to preserve the native populace. The native populace, for their part, welcomed the newcomers from the stars hospitably, making Habria one of the few recorded instances of a wholly peaceful first contact.
The natives, affectionately dubbed ‘elves’ due to their delicate features, befriended the humans. And humans, being human, well, it was discovered that the two species were capable of cross-breeding. Rather than proving sterile or mutated, the offspring proved to heavily benefit from hybrid vigor. Rather than inherit the shorter lifespan of the native population, these hybrids proved capable of living twice as long as humans. Many also displayed signs of possessing psychic powers.
As time passed, both the native ‘elves’ and the original ‘humans’ vanished from Habria in favor of the hybrids. The hybrids began to spread through their section of the galaxy and eventually made contact with humans.