Marsupial Animals

Marsupial animals are the most famous animals of Australia.

They get their name from marsupium - the pouch.

Their young are born so early that they need to complete their embryonic development while nursing, which in most species occurs in their mother’s pouch.
Eastern Grey Kangaroo (MacropusGiganteus) Joey and Mother, Wilson's Promontory Nat'lPark, Australia
Kangaroo. Poster by AllPosters. Click on thumbnail to buy

A red kangaroo for example is about the size of a honeybee when it is born only 33 days after fertilisation.

Koala (Phascolarctos Cinereus) Mother with Baby in Eucalyptus Tree, Australia
Koala. Poster by AllPosters. Click on thumbnail to buy

Marsupials and Continental Drift
Marsupials are one of the largest and most successful groups of native mammals in Australia. The reason for this unique fauna is Australia’s long isolation from other continents. When the super-continent Pangaea broke up about 200 million years ago, reptiles still ruled the world. Dinosaurs were very successful - although small mammals existed, they never got a chance to dominate the Animal Kingdom.

Once the dinosaurs got extinct by what is believed to be a sudden climate change caused by a meteorite or a volcano (theories vary), Pangaea had already drifted apart to form two continents: the northern Laurasia, and the southern Gondwana. All of a sudden mammals got the chance to develop into many different species, and it so happened that on Laurasia, they developed into placental animals, and on Gondwanaland they developed into marsupials.

Common Brushtail Possum (Trichosurus Vulpecula), Pebbly Beach, Marramarang National Park, Australia
Possum. Poster by AllPosters. Click on thumbnail to buy

Marsupials and Placental Animals
When the Gondwana continent broke up, India got attached to Asia, Africa to Middle East and South America to North America. Marsupial and placental animals were joined, and marsupials got extinct.

Australia was never connected to any other continent, and here they survived. South America still has a few species of opossums, but generally placentals were more successful, or perhaps because in placental world there were more large predators (there are no large carnivorous animals in Australia), marsupials didn’t survive.

Close-Up of a Common Wombat (Vombatus Ursinus)
Wombat. Poster by AllPosters. Click on thumbnail to buy

Marsupial Animals and Convergent Evolution
It is interesting how placental and marsupial animals developed in separation. Animals that fill similar niches in both hemispheres look remarkably similar, although they have developed totally independently. Look at Australian animals - a marsupial mouse looks like a mouse of the Northern Hemisphere, a marsupial mole has got features like a mole of the Northern Hemisphere, and a sugar glider looks like a flying squirrel. Just because they lived in similar environments and used similar strategies they developed similar features in what is called convergent evolution.

You Are Secure!

Bookmark and Share

[?] Subscribe To This Site

follow us in feedly
Add to My Yahoo!
Add to My MSN
Subscribe with Bloglines