Wallace Line by the Sahul Shelf to New Guinea. The biogeographic boundary known as Lydekker's Line, which separates the eastern edge of Wallacea from the Australian region, has a similar origin to the Wallace line. During ice age glacial advances, when the , both Asia and Australia were united with what are now islands on their respective continental shelves as continuous land masses, but the deep water between those two large continental shelf areas was, for over 50 million years, a barrier that kept the flora and fauna of Australia separated from those of Asia. Wallacea consists of islands that were not
Line of Actual Control Line of 1899 as the boundary. In a letter dated 7 November 1959, Zhou told Nehru that the LAC consisted of "the so-called McMahon Line in the east and the line up to which each side exercises actual control in the west". During the Sino-Indian War (1962), Nehru refused to recognise the line of control: "There is no sense or meaning in the Chinese offer to withdraw twenty kilometers from what they call 'line of actual control'. What is this 'line of control'? Is this the line they have created by aggression since the beginning of September? Advancing forty or