Lynn Margulis is an ardent supporter of the Gaia hypothesis: the idea that due to the finely balanced interdependence of all life forms, the planet functions as a single, giant cell. She argues that no organism is an island, and that all are linked to each other. Written with tremendous zest and authority The Symbiotic Planet traces the evolution of Earth from the origins of life and sex to the emergence of 'hyperseas' and an eerie future she describes for humanity.