Research overview: the island tigers of Bali, Java, and Sumatra

The Sunda islands once held three tiger populations, of which only the Sumatran survives; the Bali and Javan tigers are extinct. This overview examines how these island forms figure in tiger taxonomy. Under the traditional scheme each was a separate subspecies, while the two-subspecies arrangement groups all three as the Sunda subspecies Panthera tigris sondaica. It reviews evidence that the Sumatran tiger is the most genomically distinct living tiger, with small body size linked to island adaptation, and discusses ancient DNA work on the extinct Bali and Javan forms. The piece explains why the island tigers are central to the lump-versus-split debate: they show real divergence from mainland tigers, supporting at least a mainland-Sunda division, even where finer island distinctions are contested.