Fascinating facts about Australia

We have been re-reading Bill Bryson's fantastic (and hilarious) travel book about Australia called "Down Under" as well as "The Lonely Planet Australia."

Here are some of the fascinating facts we have gleaned:

GEOGRAPHY

• Australia is the only island that is also a continent and the only continent that is also a country.

• Australia's population is small by world standards - only about 20 million. China grows by a larger amount every year.

HISTORY

• It is conjectured that Aborigines arrived in Australia about 46,000 years ago, at a time of lower sea levels, during the ice age. They came via South East Asia and had to cross water passages at least 70 km's wide

• The first colonists from Europe nearly starved to death waiting for shipped in supplies rather than finding out what the indigenous population was eating.

• Several of the early European explorers were so convinced that they would encounter mighty river systems or even an inland sea that they took boats with them into the interior. Thomas Mitchell, who explored vast tracks of New South Whales and Victoria in the 1830's, dragged two wooden skiffs over 3000 miles of arid scrub without once getting them wet, but refused to the last to give them up.

• The gold rush of the 1850's marked the end of Australia as a penal colony and its beginning as a nation. In less than a decade, the country took in 600,000 new faces, more than doubling its population.

LANDMARKS

• When Sydney's city burghers decided to put a bridge across the harbour, they determinded to make it the longest bridge in the world. Stretching 1650 feet, it took almost 10 years to build. Just before it was completed in 1932, the Bayonne Bridge in New York quietly opened and was found to be 25 inches longer.

DANGEROUS CREATURES

• Five of Australia's creatures - the funnel web spider, box jellyfish, blue ringed octopus, paralysis tick and stone fish are the most lethal of their type in the world.

• Australia is home to 10 of the world's 15 most venomous snakes.

• Of Australia's 155 species of land snakes, 93 are venomous.

• The Australian Taipan is the most poisonous snake in the world with a lunge so swift and a venom so potent that your last mortal utterance is likely to be: "I say, is that a sn-"

GEOLOGY

• For the last 90 million years, Australia has been geologically comatose. It was too flat, warm and dry to attract glaciers, its crust to ancient and thick to be punctuated by volcanoes or folded into mountains. Under such conditons, no new soil is created and the old soil is leached of its goodness, making much of Australia's soil infertile.

• Ayer's Rock (Uluru) is the eroded stump of a mountain that 350 million years ago was the height of the Andes.

AMAZING CREATURES

• The largest roo 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

• One of the most common marsupials in Australia are nocturnal rat like creatures called antechinus. They live for only 11 months, the first 10 of which are spent eating and growing. Then their minds suddenly become obsessed with sex, so much so that they forget to eat and sleep. Instead, they gather in groups and try to woo passing females with serenading squeeks. By the end of August, just two weeks after reaching puberty - every male is dead, exhausted by sex, and by carrying around swollen testes.

• 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.