Wallace Line to the west of the Philippines. Wallace's studies in Indonesia demonstrated the emerging theory of evolution, at about the same time as Joseph Dalton Hooker and Asa Gray published essays also supporting Darwin's hypothesis. Understanding of the biogeography of the region centers on the relationship of ancient sea levels to the continental shelves. Wallace's Line is visible geographically when the continental shelf contours are examined; it can be seen as a deep-water channel that marks the southeastern edge of the Sunda Shelf which links Borneo, Bali, Java, and Sumatra underwater to the mainland of southeastern Asia. Australia is likewise connected
Blakiston's Line and spiders, Hatta’s line (Soya line): for reptiles, amphibians and freshwater invertebrates, Hachisuka’s line for birds and Miyake’s line for insects. There has been speculation about why Blakiston was the person who discovered this faunal boundary line and no one before him had done so. Andrew Davis, who has been a professor at Hokkaido University for four years, argued that this may have been because of his unusual position in Japanese society as a European"." Blakiston spent much time researching bird species in Japan. At that time, Japanese ornithology was at its infancy. In 1886 Leonhard Stejneger remarked: "Our knowledge