Separatist societies

Genders live apart, with little intermingling or only at fixed times.

• Eleanor Arnason. A Woman of the Iron People and Ring of Swords (1993)
• Joanna Russ. The Female Man
• Sheri S. Tepper. The Gate to Women's Country
• Sheri S. Tepper. A Plague of Angels (1993) (one community has men and women living separately)

Plus see all the stories in which the gender ratios are skewed.