Australia’s mammal fauna has been shaped from around 40 million years of isolation from the other continents in the world. The monotremes and marsupials have a higher percentage of endemics than the bats and rodents, with the latter likely to be much more recent arrivals in Australia (perhaps as recent as 1 million years ago). Prior to this, as with other continents, mammal megafauna roamed Australia during the Miocene, Pliocene and Pelistocene. Animals like Procoptodon goliah (a 200kg, 2 metre tall kangaroo), Zygomarturus trilobus (a 500kg, 2.5 metre long ‘wombat-like’ diprotodontid), Thylacoleo carnifex (a 160kg, 1.5 metre long marsupial lion) and Zaglossus hacketti (a 30 kg, 1 metre tall echidna) would have roamed Australia along with the early Aboriginals. What caused their extinction is subject to much debate, with the latest evidence suggesting that many may have been hunted to extinction around 45,000 years ago, with the extinction of the remaining species linked to the last ice age, which occurred at the end of the Pleistocene, around 13,000 years ago.