Australia and its surrounding islands contain a significant proportion of the world’s mammalian diversity, including the only monotremes (egg-laying mammals) as well as a great diversity of marsupials (pouched mammals) and many eutherian mammals such as bats and rodents. More than 300 terrestrial mammalian species are native to Australia, and 87% of these are found nowhere else. This level of unique biodiversity brings value to Australia at economic, social and scientific levels.
Australia’s unique biological diversity is a result of the continent’s long-term isolation. Over the past 40 million years the Australian continent has been completely isolated from other landmasses and has been drifting slowly northwards as a giant antipodean ark. This period of isolation has allowed much of our fauna to evolve, diversify and adapt independently of other continents.
For example, bats have a long evolutionary history in Australia, with multiple lineages independently colonising the continent from Asia and potentially also from South America before radiating into many unique species. Rodents have also invaded from Asia in two waves over the past five million years, resulting in the rapid evolution of diverse native species. Thus, Australian mammals provide many different answers to the question of how to survive and even thrive over the long-term on this...
