Austral Physical Geography & Ecology
is the world’s smallest continent and the second least populous.
It is also the only continent in the world to be entirely under the
government of one country—which makes it the sixth largest country in
the world and the largest in the region. It covers 2,967,909
*Australia only has one major series of mountains, the Great Dividing
Range, which does create a continental divide, separating the western
watershed from the eastern watershed. It is actually a series of
small ranges, none of which are much higher than the Appalachian
Mountains. The highest point in the range (and in Australia),
Mount Kosciuszko, is 7,310 feet high.
*Australia has one other major highland area, the Western Plateau in
central and western Australia. It covers almost 2/3 of the
country and is fairly arid.
*The dry interior of Australia is known as the outback, and is not good
for much except some grazing on vast ranches called stations.
Because only 10% of the land is arable, it is sparsely populated.
*Most of the outback is outright desert: (clockwise from north)
the Great Sandy Desert, the Gibson Desert, and the Great Victoria
Desert, as well as the Nullarbor (no tree) Plain.
*There are some small rivers in Australia, notably the Darling River and the Murray River in the southeast.
*In theory, Australia also has a large lake, Lake Eyre. However,
most of the time this lake is just a nearly-dry basin in the outback
with just a few small lakes or mudflats to show where the entire lake
should be. During the rainy season, the lake may fill up to 5
feet deep, and a few times a century (perhaps 4 times in 100 years) it
will fill to about 13 feet deep. The salt pans of the Lake Eyre
Basin are the lowest point in Australia, being about 50 feet below sea
*Because the interior of Australia is so inhospitable (being mostly
desert and steppe, with a little savannah, most people live along the
coast, which enjoys Mediterranean climates along the southwest, marine
west coast climates along the southeast, and humid sub-tropical
climates along the northeast.
*Australia does not have much tectonic activity today, despite being
very near one of the most tectonically active places in the world, the
Ring of Fire.
*Many of the islands of Oceania were created by volcanic activity, and
volcanoes still erupt fairly frequently in the region.
*New Zealand is part of the Ring of Fire, and it has a number of active
volcanoes and its national parks feature hot springs, geysers, and
other wonders of geothermal energy.
*New Zealand’s climate is essentially all marine west coast, while most
of the rest of Oceania, including Papua New Guinea, is primarily
tropical rainforest in its climate and vegetation.
*Antartica, the 5th largest continent in the world, covers about 5.4
million square miles. Almost all of it is covered by ice, and
almost all of it can be considered desert, because it receives almost
no precipitation during the year. Technically, a desert may be
defined as a place receiving less than 10 inches of rainfall a year
(although Köppen allows temperature to supersede that, making
Antarctica a Polar climate).
*Most of Antarctica is covered by ice sheets about 1½ miles
thick, some of which extend out over the ocean, apparently enlarging
Antarctica during the winter (and melting to form icebergs in the
summer). Some of these ice shelves are semi-permanent, most
notably the largest of them, the Ross Ice Shelf, which covers over half
the Ross Sea.
*Most of the scientific research stations in Antarctica are on the
Antarctic Peninsula (where temperatures occasionally rise above
freezing—into the upper 30s), sometimes known as Palmer Land (the
American name) or Graham Land (the British name), although currently
the northern part of Palmer Land and the southern part is Graham Land.
*The Geographic South Pole, the point through which the imaginary axis
on which the earth rotates passes, was found on 14 December 1911 by
Roald Amundsen of Norway—an American team led by Robert Falcon Scott
found it a month later, but died on the way back to the coast.
*The relative isolation of this region from the rest of the world
(which was once greater, as Australia and Melanesia are on their own
tectonic plate) has allowed it to develop a unique ecology beyond the
Wallace Line (located between Borneo and Celebes).
*Almost all of the world’s marsupials and all of the remaining
monotremes live in Australia, New Guinea, or New Zealand (or right
around them). Mammals elsewhere are mostly placental mammals.
*Monotremes are mammals that lay eggs, notably the echidna and the platypus (one of very few poisonous mammals in the world).
*Marsupials are creatures that give birth to babies that are not
sufficiently developed to live on their own. They are then raised
in pouches on their mother’s bodies where they nurse and continue
growing. This makes it less likely that the young will survive
birth and youth, but greatly reduces the mother’s chances of
complications with pregnancy.
*Most of Australia’s famous animals are marsupials: the kangaroo,
the wallaby, the koala (which is not a bear at all), and many other
creatures. Almost all of Australia’s animals are unique to the
continent, and fill niches normally filled by other creatures elsewhere.
*Australia does have a few placental mammals, notably a type of wild
dog called the dingo, but this is thought to have been introduced by
the Aborigines perhaps as recently as 5,000 years ago.
*Australia also has the widest variety of venomous creatures in the
world, and is the only place to have more poisonous than non-poisonous
*Australia has a major problem today with invasive species:
species brought from outside the region that have spread uncontrolled
by any local predators. Wild rabbits (which eat grass and crops
are a serious problem), but so are wild cats, wild goats, wild pigs,
certain types of toads (brought in to eat up an earlier invasive
beetle), and wild camels.
*It is thought that, by eating up native plants, rabbits alone have
wiped out an untold number of native plant species and because so many
animals ate those plants, they have also rendered 1/8 of all mammalian
species in Australia extinct as well.
*Australia has made serious efforts to control the rabbit population,
even attempting biological warfare in 1950, when a disease that kills
rabbits was released. This killed off 5/6 of the rabbit
population, but since then they have developed a resistance to it.
*Today, Australia is very careful to prevent the importation of any unapproved animal or plant live into the country.