 These stories are set a century or two after a race of mysterious and omnipotent aliens, the Invaders, have almost completely eradicated humans from the Earth (they regard whales and dolphins to be the superior Terran lifeforms and humans as only a dangerous infestation).But humans have inhabited virtually every other corner of the solar system, often through the use of biological modifications learned, in part, by eavesdropping on alien communications.Varley's "Overdrawn at the Memory Bank" was adapted and televised for PBS in 1983.