Australasia is one of the world's geographical regions. It is unified in natural history and geology because of its ancient origin as part of the supercontinent Gondwana. It is the geographical area which contains the Australasian ecozone.
Its islands are all south-east of the Bali–Lombok line, known as the Wallace Line, after Alfred Russel Wallace. The main political entities are Australia, Indonesia, New Zealand, and Papua New Guinea. The main islands are:
Australasia's region is Oceania. It includes Australia, New Zealand, the island of New Guinea, and neighbouring islands in the Pacific Ocean.