John Polk Allen (born May 6, 1929, Carnegie, Oklahoma) is a systems ecologist, engineer, metallurgist, adventurer, and writer. Allen is a proponent of the science of biospherics and a pioneer in sustainable co-evolutionary development. He is the founder of Synergia Ranch, and is best known as the inventor and director of research of Biosphere 2, the world's largest vivarium and research facility to study global ecology. Biosphere 2 set multiple records in closed ecological systems work, including degree of sealing tightness, 100% waste and water recycle, and duration of human residence within a closed system (eight people for two years). He is also involved with forestry and reforestation in Puerto Rico where he owns a 1000 acre Mahogany tree farm at Patillas.