Why did the men and women in Vandread split up to begin with?
Once upon a time, in the future (roughly two thousand years from now), a colonist ship departed Earth, heading for the stars on it's journey to discover a new world to populate for the human race. This journey proved successful with the discovery of not one but two neighbouring planets suitable of colonisation. However, the colonists grew into conflict with each other - A conflict that divided the crew by gender! The men settled on one planet, which was dubbed Taraaku while the woman settled for the neighbouring planet, Mejarru.


I couldn't find much to support this but it sounds like something that fits the anime.

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