Evolution of Sousa chinensis: A scenario based on mitochondrial DNA study

Hypothesis of the origin and dispersal of the Sousa chinensis in the Indo-Pacific and Australian waters. Sousa chinensis originated in the east of Australian waters (cross shade), and spread west into the Indo-pacific area through the Torres Strait. A part of the dispersal population continued east through the Malacca strait, while the other part moved north to the South China Sea. The dot shade illustrates the contour of Southeast Asia and Austral-Asia 120 m below present sea level (mod. from Voris, 2000). The minor box in the top right corner shows the present distribution of Sousa chinensis in shallow coast water of the West Pacific Ocean (mod. from Jefferson et al., 1993; Rice, 1998).