Return To Eden is a 1988 science fiction novel by American writer Harry Harrison. The novel is the third and final volume in Harrison's Eden. The first two stories of the trilogy are West of Eden and Winter in Eden. The novel tells an alternate history of planet Earth in which the extinction of the dinosaurs never occurred. There is a war between a group of Cro-Magnon-level humans, who are descended from New World monkeys, and a reptilian race called Yilanè, who are descended from the prehistoric mosasaur and have become the dominant lifeform on the planet.