At the northern tip of the Philippine island of Luzon lies Callao Cave, an expansive, seven-chamber limestone warren. In April, researchers reported in the journal Nature that they’d uncovered the bones of a now-extinct, previously unknown human species near the far end of the first chamber. The discovery adds to growing evidence that human evolution and dispersal out of Africa is much more complicated than scientists once thought — and that we’re just starting to understand Southeast Asia’s role in that story.