Why are koalas not found in western Australia and Tasmania?

Answer 1

Kangaroos are not limited to Australia, as tree kangaroos are found on the island of New Guinea.

However, the animal most commonly recognised as the kangaroo is native only to Australia because most of the countries used to be connected as a land called Gondwana. Kangaroos had probably inhabited the northern part of this land, (now known as Australia) due to the climate or just the way that God made it. When areas of Gondwana started breaking off and forming countries, the kangaroos stayed on their original habitats and thus were sectioned off into Australia. Some stragglers may have existed in other countries but died out due to climate, diet, habitat or inability to reproduce or, most likely, predators. The absence of large predators enabled relatively defenceless creatures such as the koala to proliferate. Prior to the advent of European settlers, there were many more native marsupial species in Australia, but with man came more predators, in the form of cats, dogs and foxes. Even the humble rabbit is a threat to Australian wildlife because it eats so much of the native animals' food.

Answer 2

Because that's where they developed. And Australia is a far way from anywhere else, separated by a lot of water, so they couldn't spread out.
They are native to it
According to geological history, Earth as we know it was once very different. All the continents were once joined to form a huge "super continent" call Pangaea. As years passed life forms evolved, but as they did so, the continents gradually began to drift apart creating the world as we know it today. During the process of continental drift, different species of animals became stranded on sections of land including the kangaroos which inhabited most of Australia. Land bridges were cut off and over time each continent became completely surrounded with water making it impossible for animals to leave. Kangaroos and many other species of animals around the world are unique to their continent. Today, the remains of ancient bones and geological records are left around the world to link animal migration and isolation as evidence of the days when Earth was young.

It is important to note that animals like the kangaroo have survived in great numbers because of the absence of predators in Australia. The continent lacks the large carnivorous predators found in Africa, Asia and the Americas, and this has enabled defenceless species like kangaroos to survive. They are more than a match for Australia's only true land predators, the Tasmanian devil and the now-extinct Thylacine (Tasmanian Tiger), both of which once roamed the mainland. The arrival of the dingo thousands of years ago did result in the extinction of some smaller species (including the Tasmanian devil and Thylacine from the mainalnd), but has made no impact on the kangaroo population.

Answer 3

Human activity caused the extinction of koalas in Western Australia, but they have since been re-introduced. Small colonies of koalas are thriving in that state.

There is no fossil evidence to indicate that koalas ever moved to Tasmania from the mainland.

Answer 4

The main reason is the lack of natural predators.

Australia is isolated geographically from the rest of the world, being an island continent. This has allowed relatively defenceless animals in the marsupial family to thrive without many natural predators. Even marsupial carnivores such as the Tasmanian devil and Thylacine fitted the niche perfectly: the arrival of dingoes thousands of years ago led to the extinction of both of these carnivorous marsupials from the mainland.

Answer 5

Koalas are native to Australia because their food source is specific to Australia.

While there are hundreds of different eucalyptus species in Australia, koalas eat from only about 60 of the species, consuming about half a kilogram of eucalyptus leaves every day. Koalas will not eat all types of eucalyptus, feeding on just 14 species as their primary food source, specifically, the subgenus Symphyomyrphus. Preferred eucalyptus species vary depending on their locality, so that the species eaten by Victoria koalas will be different to those eaten by north Queensland koalas.

Answer 6

Continental drift.

Marsupials, including kangaroos, once lived on the ancient continent Gondwana, which split into Antarctica, Australia, and South America. There was an absence of large predators on the Australian continent, so animals such as kangaroos were not threatened, and proliferated.

There are other marsupials on other continents, but because these continents have carnivorous predators, fewer species of marsupials have survived.

Answer 7

Quite simply, there are no similar biomes anywhere else in the world.

Australia has over 600 species of eucalyptus trees, in various shapes and sizes, and these species make up the majority of native bushland in Australia of the sort that is favoured by kangaroos for their habitat. This particular biome is not found anywhere else. Wallabies, however, have been introduced to other countries, and they have thrived in different types of biomes, as long as there is food they can eat.

Answer 8

Koalas are uniquely adapted to life in Australia. Only Australia has the right conditions and proper food sources to ensure their survival in the wild.