Prehistory
Further information: Prehistory of the Philippines
The metatarsal of Callao Man is reported to have been reliably dated by uranium-series dating to 67,000 years ago[22] thereby replacing the Tabon Man of Palawan, carbon-dated to around 24,000 years ago,[23][24] as the oldest human remains found in the archipelago. Negritos were among the archipelago's earliest inhabitants, but their appearance in the Philippines has not been reliably dated.[25] There are several opposing theories regarding the origins of ancient Filipinos. The most widely accepted based on linguistic and archeological evidence, is the "Out-of-Taiwan" model, which hypothesizes that Austronesians from Taiwan began migrating to the Philippines around 4000 BCE, displacing earlier arrivals.[26][27]
Other hypotheses include Wilhelm Solheim's Island Origin Theory[28] which postulates that the peopling of the archipelago transpired via trade networks originating in the Ice Age Sundaland area around 48000 to 5000 BCE rather than by wide-scale migration; and F. Landa Jocano's Local Origins Theory which postulates that the ancestors of the Filipinos evolved locally. Whatever the case, by 1000 BCE the inhabitants of the archipelago had developed into four kinds of social groups: hunter-gatherer tribes, warrior societies, highland plutocracies, and maritime harbor principalities.[29]