- The Wallace Line is a faunal boundary line drawn in 1859 by the British naturalist Alfred Russel Wallace that separates the ecozones of Asia and Wallacea (a transitional zone). - West of the line are organisms of Asian origin (e.g., tigers, monkeys, elephants), while east of the line are organisms of Australasian origin (e.g., marsupials, cockatoos). - It runs through the Malay Archipelago, between Borneo and Sulawesi (Celebes), and through the Lombok Strait between Bali and Lombok.