Here is a ‘surprise.’ Another creature appears to have the mouth of a duck, the body of an otter and the tail of a beaver.” | Find Wildlife

Australia is a long from nowhere and it has been a very long time. The country clearly separated from the supercontinent of Gondwana 40 million years ago, and since then, it has existed – as a large area in the middle of an even larger ocean – in a beautiful isolation.

This fragmentation, combined with different habitat types and changing global temperatures, suggested a unique evolution.

Australia is now home to a high proportion of species found nowhere else. About 85 percent of the continent’s mammals, 93 percent of its reptiles and 94 percent of its frog species are unique to this continent.

When the split occurred, there were no mammals living in Australia, but there were ancient lineages of marsupials and monotremes (egg-laying animals).

These survived and diversified, leading to the evolution of the 300 or so modern marsupial species, including bandicoots and quolls, and two living species of Australian monotreme, the platypus and the short-lipped echidna.

Here, ‘miracle’ abounds. For example, the platypus appears to have the mouth of a duck, the body of an otter and the tail of a beaver.

It lays skin eggs like a reptile, yet feeds its young with milk like a mammal, with special openings in the stomach that leak a liquid that is absorbed through its fur. Males have venomous ankle spurs, while their lips are electrified.

Echidnas are covered in spikes and can detect electricity, but it’s their reproductive system that takes the spotlight. Males have a distinctive, four-headed button, while females have two separate holes.

In fact, some male marsupials, including opossums, have a double-sided penis, which delivers sperm to the female’s two breasts. Females also produce a third, temporary female organ, which they use to give birth.

And let’s not forget, marsupials are big on bags. These provide a safe haven for their young babies, who are born immature and embryo-like after a short gestation period.

To the uninitiated, all these features may seem strange. But look at them through an evolutionary lens and they make perfect sense.

How do these amazing features help Australia’s amazing animals?

Each ‘surprise’ piece represents a solution to a survival problem, which is also related to the animal’s lifestyle and habitat, which are themselves related to their home continent of Australia.

When it swims with its eyes closed and nostrils closed, electro-sensing cells in its mouth help the platypus detect the electrical signals produced by the muscle movements of its prey.

Glands on the upper part of the male’s thigh make a poison, which is then released through the ankles, and is used as a weapon when fighting other males for territory or mating rights.

Meanwhile, the Echidna’s spikes are self-defensive, while the males use two of the four heads of their penis at the same time, then alternate with one successive mating.

This is thought to help increase the chances of successful fertilization, especially when females come into contact with many males during breeding.

The reproductive system of the echidna has evolved in the same way as that of its loved ones, although the same process has evolved in opossums, the addition here of a third female, a temporary reproductive system helps the passage of the small embryonic baby from the womb to the bag, where it can continue to grow safely.

Australia’s wildlife is some of the strangest, yet most magnificent in the world – nowhere else like it.

Above image: a platypus swimming in a log. Credit: Martin Harvey/Getty Images