Wallace Line Wallace Line The Wallace Line or Wallace's Line is a faunal boundary line drawn in 1859 by the British naturalist Alfred Russel Wallace and named by English biologist Thomas Henry Huxley, that separates the ecozones of Asia and Wallacea, a transitional zone between Asia and Australia. West of the line are found organisms related to Asiatic species; to the east, a mixture of species of Asian and Australian origin is present. Wallace noticed this clear division during his travels through the East Indies in the 19th century. The line runs through Indonesia, between Borneo and Sulawesi (Celebes), and through the
Indomalayan realm Indomalayan realm The Indomalayan realm is one of the eight biogeographic realms. It extends across most of South and Southeast Asia and into the southern parts of East Asia. Also called the Oriental realm by biogeographers, Indomalaya extends from Afghanistan through the Indian subcontinent and Southeast Asia to lowland southern China, and through Indonesia as far as Java, Bali, and Borneo, east of which lies the Wallace line, the realm boundary named after Alfred Russel Wallace which separates Indomalayan from Australasia. Indomalaya also includes the Philippines, lowland Taiwan, and Japan's Ryukyu Islands. Most of Indomalaya was originally covered by forest,