To escape the notice of rival tribes and the huge, lanky insectoid predators on Geonosis, the Geonosians lived in underground hives.
A hive was divided into three main castes: queen, aristocrat, and drone. Drones were further divided into several subcastes.
Queens gave birth to all members of a colony, and were therefore the most important beings in it. A queen's only function was to lay eggs. They lived in the dark catacombs beneath the spire-hives, immobile and massive, where blind drones attended to their needs.
Aristocrats, composing 5% of Geonosis' population, ruled the Geonosians, including the queen. They were disdainful of drones and other species, and very competitive, using their armies of soldier drones and battle droids to fight each other. The drones were the lowest caste of Geonosians, born to work.
Subcastes amongst the drone population divided them further into pilots, soldiers, farmers, and so forth. All drones were nameless, as they were considered by the aristocracy to be interchangeable. Drones could win prestige in the combat arenas, and could rise above their station.
Geonosian hives included: