Southeast Asia Philippines. The eastern half of Indonesia and East Timor (east of the Wallace Line) are considered to be biogeographically part of Oceania (Wallacea) due to its distinctive faunal features. New Guinea and its surrounding islands are geologically considered as a part of Australian continent, connected via the Sahul Shelf. The region was already inhabited by Homo erectus from 1,000,000 years ago during the Middle Pleistocene age. "Homo sapiens" reached the region by around 45,000 years ago, having moved eastwards from the Indian subcontinent. Rock art (parietal art) dating from 40,000 years ago (which is currently the world's oldest) has been
Alfred Russel Wallace the Cambridge University Museum of Zoology. His observations of the marked zoological differences across a narrow strait in the archipelago led to his proposing the zoogeographical boundary now known as the Wallace line. Wallace collected more than 126,000 specimens in the Malay Archipelago (more than 80,000 beetles alone). Several thousand of them represented species new to science. One of his better-known species descriptions during this trip is that of the gliding tree frog "Rhacophorus nigropalmatus", known as Wallace's flying frog. While he was exploring the archipelago, he refined his thoughts about evolution and had his famous insight on natural selection.