A theory conceived by Alfred Crosby in his 1986 book Ecological Imperialism: The Biological Expansion of Europe, 900–1900, which proposes that colonization was not only a form of cultural and political tyranny, it was also a form of environmental terrorism. Indeed, Crosby goes so far as to argue that the ecological dimension was in fact primary. His reason for suggesting this is the evident fact that wherever colonists settled they brought with them diseases that devastated the local populations (of both people and plants and animals) as well as invasive pests and weeds that encroached on the existing flora and fauna, and eventually starved them out of existence. European-style agricultural practice utilized in dry regions like Australia and South Africa has had a catastrophic environmental impact. Crosby's work has sparked an enhanced interest in the role and significance of the environment in understanding colonial history in Postcolonial Studies.