Australia and the islands of Oceania are ancient lands that have been isolated from other continents for millions of years. That is why 84% of Australia’s mammals and plants and almost half of its birds cannot be found anywhere else in the world. These include the koala, kangaroo, platypus, echidna, brush-tailed possum and wombat, and birds like the emu and the kookaburra. Other native animals include reptiles like crocodiles, snakes and lizards.Note: The tuatara, the most ancient reptile, is found in New Zealand. It can live for up to 100 years.