Why does only Australia have kangaroos?

Answer 1

Marsupials evolved when Australia, Antarctica and the Americas were all joined together. When they separated, placental mammals evolved and quickly replaced marsupials except in Australia and New Guinea. A few marsupials survived in the Americas, the opossums.

In Australia there was always a water barrier between Asia and Australia. This is called the Wallace Line after Alfred Wallace whose work on evolution was read to the Linnaean Society at the same time as Darwin's. On the Asian side of the Wallace Line are placental mammals, on the Australian side are the marsupials.

A few placental mammals have arrived in Australia, bats, rats and mice, and they have evolved further here but most ecological niches are taken by marsupials.

Kangaroos are the grazers - they are to Australia what the placental bison, sheep, antelope, horses etc are to the other continents.

Australia is not the only country with kangaroos, New Guinea has some native wallabies and tree kangaroos and there are feral wallabies in New Zealand and the UK.

Answer 2

The first mammals laid eggs a few of these stored those eggs in a pouch. Then some began giving live birth to undeveloped young, these were marsupials. Before placental mammals developed however, Australia became separated from the rest of the world. This isolation prevented placental mammals from getting there. When the placental mammals developed elsewhere they were so much better at reproducing that they replaced almost all the marsupials of the world. Only the Opossum and pygmy opossums escaped extinction.

Answer 3

There are many species in Australia found nowhere else (naturally). Australia is an island, and seperated from larger land masses hundreds of millions of years ago.

Animals and plants on Australia after it separated went down their own evolutionary paths, and the species that came about didn't have any way of travelling to the rest of the world (until of course man came along.)

Answer 4

Because both Australia and Kangaroos are awesome. So they go together. Like wombats and Australia. And English convicts and Australia.

Sincerely,
Your future queen of Australia (And Avocado juggler, and pretzel folder, and of course, walrus trainer)

Answer 5

Just a mammal that evolved living on an island continent TLC or the discovery channel not to be rude but u do have internet right