The Ingavi are a primitive humanoid species. They are related to the Jumerians, who believe them to be representative of their evolutionary precursors. The Ingavi have no spoken or written language and communicate through signs. Unlike the jumerians, the Ingavi did not become technologically advanced. Early in their shared history, the jumerians came into conflict with the Ingavi and polluted their homeland. As a result, the Peladon erected an energy barrier over the Ingavi's territory on the southern continent for their protection. The jumerians eventually developed in a warp-capable civilization, while the Ingavi remained a tribal hunter-gatherer society.