Biosphere 2Rises From Southern Arizona's High Desert Like An immense greenhouse spaceship. Packed with 3,800 carefully selected plant, animal, and insect species, this terrarium is one of the world's most biodiverse, lush-and artificial-wildernesses. Only recently transformed from an abandoned ghost dome to a University of Arizona research center, the site marks one of the largest ecology experiments ever undertaken; and it was the setting of a grand drama about humans and the Earth at the end of the twentieth century.