In ancient Earth, humanity faced an existential crisis and split into two factions:
The interstellar sailing faction chose to leave the earth and carry out deep space colonization and genetic adaptation projects to survive.
The left-behinders on Earth choose to stay on Earth and stick to the "pure" human genes and homeland. In order to adapt to the extreme cosmic environment, Star Navigators' genes were modified to obtain the "Consciousness-Guided Gene Absorption (CAGA)" ability. It can unconsciously or consciously absorb favorable gene fragments from the surrounding environment (microorganisms, alien creatures, and even elements), temporarily or permanently change its own form and abilities (elementary, animal, plant, etc.), And can transform back into human form with the dominant consciousness of "humanity".
Years of gene absorption and fusion have resulted in the Star Navigator's "human" dominant gene chain being extremely unstable. The mutations are becoming more frequent and violent, and are accompanied by severe loss of sanity, insanity, and even irreversible permanent alienation (becoming a real "other than human" monster). They urgently need the most original, stable, and unmodified "pure human genes" as anchors and repair templates.
The Star Voyager fleet returned to the solar system with overwhelming technological power, instantly blocking all exits and quickly taking control of the earth. They:
Disarm all Mortians' weapons and smart devices (to prevent resistance and information leakage).
All Mortians were forced to isolate themselves at home, and basic survival supplies were uniformly distributed by Star Navigators.
On the surface, they maintain order and do not engage in unnecessary killing or obvious abuse, but the essence is to "imprison" them as precious gene pools.
