Biosphere Project buildings seen at dusk. The Biosphere is a privately-funded experiment, designed to investigate the way in which humans interact with a small self-sufficient ecological environment, and to look at possibilities for future planetary colonisation. The $30 million Biosphere covers 2.5 acres near Tuscon, Arizona, and is entirely self-contained. The eight 'Biospherians' will share their air- and water- tight world with 3,800 species of plant and animal life over their two-year stay in the building, producing all of their own food and supporting the whole environment in five 'biomes'; agricultural, rain forest, savannah, ocean and marsh.