Forty Thousand in Gehenna
C. J. Cherryh
 A group of 42,363 Union humans and azi are dispatched to set up a base on a very rare habitable planet named Gehenna II. Unknown to the settlers, their mission is designed to fail; they are deliberately abandoned in order to create long-term problems for the rival Alliance. The native Caliban are first presented as annoying lizard-like creatures. The humans at first attempt to keep them outside a perimeter or to drive them away. In time, larger and larger Caliban are seen, with differences in color, size, and even a social structure (some Caliban are subservient to the larger, different-colored Caliban). It becomes clear that the creatures are capable of communication, at least at the level of symbology, and of developing empathic or possibly telepathic links to humans. Eventually a symbiosis develops, with some of the Caliban pairing off with humans. Over a period of decades and several generations cut off from resupply, the colonists lapse into a primitive lifestyle. By necessity, the azi are allowed to raise families. The non-azi humans are in the minority from the beginning and over time, intermarry with the majority. An Alliance mission first seeks to intervene, then withdraws from direct contact, content to watch as two quasi-feudal, fundamentally opposed societies develop, while a third, smaller group called the "weirds" becomes much more closely associated with the Caliban, living with them rather than the other humans and becoming less comprehensible in the process. The novel follows several generations of descendants of one particular azi, who establish different lines and rise to become the leaders of two rival cultures. Historical moments depict the decline of the colony, the establishment of human/azi-Caliban relations, cultural development, and the planetary environment. Finally, the two cultures, one "masculine"-aggressive, the other more "feminine"-receptive, meet and fight for dominance. A Union delegation arrives at the very end, just in time to be given short shrift by Elai, the girl-ruler who has emerged victorious.