Amazing Creatures in Australia

• The largest kangaroo that ever existed was the giant short-faced kangaroo, which lived during the Pleistocene era. It grew to heights of up to 3 m!

• The saltwater crocodile is the world's largest reptile - males can reach a staggering 6 m long

• Marsupials are so energy efficient that they need to eat one-fifth less food than equivilent-sized placental mammals.

• Kangaroos hop because it is the most energy efficient way of getting around at medium speeds. The energy of the bounce is stored in the leg tendons, much like a pogo stick.

• Koalas eat gum leaves which are so toxic that they use 20% of their energy just detoxifying their food. They make up for this by having tiny brains (our human brains take up 20% of our energy.) Living in tree tops with so few predators means koalas can get by with few wits at all.

• So challenging are conditions in Australia that several of its birds (kookaburras, magpies and blue wrens toname a few) have developed a breeding system called "helpers at the nest" Young adults stay with their parents to help bring up new chicks.

• The dingo is thought to have been the world's first domesticated dog and the ancestor of all domestic dog breeds.

Source: Bill Bryson