Prehistoric Australia

Australia's ancient past shaped the extraordinary biodiversity we see today. Around 33 million years ago, Australia finally broke away from Antarctica, its last Gondwanan link, and began drifting in isolation. This separation enabled a unique evolutionary path, giving rise to remarkable creatures and landscapes found nowhere else – fanged kangaroos, strange monotremes, towering eucalypt forests and megafauna like giant wombats and huge lizards.

Follow Australia through the ages with the interactive below and see how drifting continents shaped our of remarkable biodiversity. 

The Early Miocene: 23 to 16 million years ago

By the Early Miocene, Australia had completely spilt from Gondwana and had become an island. Isolated from the rest of the world, animals began to evolve in ways seen nowhere else. This was a time of booming diversity and evolutionary experimentation.

Lush rainforests were home to distant ancestors of animals that populate Australia today. But others were far less familiar – like giant flightless birds and marsupial predators.

Step back into the Early Miocene with the interactive below and uncover the extraordinary animals that lived in Australia’s ancient landscapes.

Rainforest roos

The earliest known kangaroos were small, ground-dwelling marsupials that bounded through the fallen branches of Australia’s ancient rainforests. They were more like tree-scrambling possums than the hopping kangaroos we see today.

Meet the first kangaroos

The Late Miocene - Pliocene: 11.6 to 2.6 million years ago

By the Late Miocene, Australia's lush rainforests had shrunk as the climate became cooler and drier. Open canopy forests dominated by plants like eucalypts expanded, and grasslands spread across the continent.

During the Early Pliocene, the Australia we know today was emerging. Like today, the forests were dominated by gum and wattle trees. As the land continued to dry, grasslands expanded and wildflowers bloomed into new open spaces. Familiar animals like Budgerigars and Saltwater Crocodiles started to appear.

As the environment changed, animals changed, too. The diprotodontids, once tree-climbing creatures, started to explore the wide, open spaces. Over time they became specialised giants. They evolved to become bigger and stronger which was ideal for walking long distances.

Explore the interactive below to see how changing landscapes shaped remarkable animal adaptations, giving rise to both giants and familiar species.

The mighty Diprotodon

Diprotodon optatum was by far the largest marsupial that ever lived, and the heaviest of Australia’s megafauna, weighing up to 2700 kilograms. It was a giant specialised for walking – its long and columnar legs with stout feet helped this massive animal roam far and wide in search of shrubs and trees on which to browse. It may look a lot like a giant wombat but it’s not. While it is a relative of today’s wombats and Koalas, it belongs to an extinct family, the diprotodontids.

Pleistocene: 2.6 million to 11,700 years ago

Australia’s modern land animals aren’t all that big. There are no elephants, hippos or big cats. But the fossil record tells a different story: Australia’s animals included giants.

During the late Pleistocene, as the climate turned cooler and drier, the great interior deserts started to form, sea levels fell and grasslands spread. In response, some animals evolved into true titans: giant wombats, towering kangaroos, massive monitor lizards and fearsome pouched predators.

These ‘megafauna’ once ruled the continent. Today, we can only imagine what it would be like if they still roamed Australia.

Meet the megafauna

Short-faced king

Giant Short-faced Kangaroo, Procoptodon goliah

Meet one of the largest kangaroos of all time – Procoptodon goliah weighed over 250 kilograms. Its short face wasn’t the only odd thing about it; it also had long arms with long claws on its hands, and only one toe on each foot. Its feet and hips suggest it walked on two legs instead of hopped, and footprint evidence records them doing so.

Prehistoric brawler

Lord Howe Island Horned Turtle, Meiolania platyceps

This turtle was a prehistoric brawler. Only found on Lord Howe Island, it had horns, a tail club and a shell about a metre long. These giants were like ‘turtle-tanks’. They likely head-butted and tail-whacked rivals when fighting over resources.

The great extinction

In a wave of rolling extinctions that affected megafauna all over the world, an incredible 86 per cent of Australia’s giant land animals had disappeared by the end of the Pleistocene, 11,800 years ago. The event was so dramatic it’s referred to as ‘the Late Pleistocene megafauna extinction’.

The arguments about why they died have raged since the first megafauna fossils were discovered. There is a range of possibilities, but it is most likely related to climate change and human impact.

McGraths Flat fossil site

An exceptional, recently discovered site is McGraths Flat in New South Wales. This site is a Konservat-Lagerstätte, or a fossil site known for exceptional preservation. Fossils here have been preserved down to the microscopic level and include plants, insects and fish from around 16 to 11 million years ago. These fossils show us what the environment was like in the past and how ecosystems change over time.

The site was identified by a local farmer and is now researched by the Australian Museum’s palaeontology team who continue to discover new species.

How was the McGraths Flat fossil site formed?

Fossil of Baladi warru

The incredible preservation at McGraths Flat offers rare glimpses into relationships between species and their environments. This fossil sawfly still carries pollen grains from a plant called Quintiniapollis psilatospora on its head. Like many sawflies today, Baladi warru was a pollinator.