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
Line of beauty Line of beauty Line of beauty is a term and a theory in art or aesthetics used to describe an S-shaped curved line (a serpentine line) appearing within an object, as the boundary line of an object, or as a virtual boundary line formed by the composition of several objects. This theory originated with William Hogarth (18th-century English painter, satirist, and writer), and is an essential part of Hogarth's theory of aesthetics as described in his "Analysis of Beauty" (1753). According to this theory, S-shaped curved lines signify liveliness and activity and excite the attention of the viewer as contrasted