Get Regular Updates!
|Unearthing ancient Australia winds back the clock millions of years



Sheepbaa, via Wikimedia Commons*

Unearthing ancient Australia winds back the clock millions of years

Unearthing ancient Australia winds back the clock millions of years

What did prehistoric life look like in Australia? The skeletons of ancient creatures buried for millions of years are shedding light on marsupial evolution.

Unearthing ancient Australia winds back the clock millions of years

Beneath the dry, dusty landscape of a sprawling South Australian cattle station lies an ancient graveyard.

Twenty-five million years ago, Etadunna Station was a lake surrounded by woodland.

Now, its treasure trove of prehistoric fossils are helping scientists unravel the mysteries of life on Earth aeons ago.

View Larger
Image|Judd Case/East Washington University
“We’re working on a million-acre cattle station. It’s dry and sparse. Etadunna Station, named after the rocks,” says Judd.

Dental detective work

WA Museum palaeontologist Dr Kenny Travouillon is an expert on bandicoot and bilby evolution.

Kenny analysed fossils collected from Etadunna by US researchers to shed light on the marsupials’ evolution.

Comparing the teeth of modern bilbies and their distant ancestors shows how their diet changed over time.

Kenny combined his dental detective work with geological data from other scientists. These records show what the climate was like by way of chemicals in the atmosphere added to the soil by plants.

Slowly, these puzzle pieces begin to form a picture.

The big chill

During the Miocene era (roughly 23 to 5 million years ago), the tropical rainforests that once covered Australia were shrinking.

The polar caps were freezing, meaning less rain, and Earth cooled over millions of years.

Species competed fiercely over the remaining resources; causing many to change size over time.

“The bilby that was discovered there was probably the largest species by far,” Kenny says.

“It would have been about the size of today’s lesser bilby. Everything else at that point was much smaller – the size of a mouse.”

But it wasn’t alone.

Hop to it

The first hopping kangaroos evolved from their rainforest-dwelling ancestors to cover vast plains in search of food and mates.

Small cat-like marsupials called dasyurids hunted ground-dwelling bilbies and bandicoots. The quoll and Tasmanian devil are modern-day dasyurids.

“The dasyurids don’t seem to be very prevalent, whereas today, they’re the most diverse group of marsupials, with kangaroos the second most diverse,” says Kenny.

But the fossils collected at Etadunna Station met a different end – crocodile attack.


Crocodile ‘larders’

Professor Judd Case is an evolutionary biologist at Eastern Washington University. His team found the fossils at Etadunna Station by combing through ancient lake deposits.

“We find lakes with partial skeletons where crocs have pulled the animals in,” says Judd.

“It’s their larder, to come back later. Then it gets covered up and they can’t find it – until we do millions of years later.”

But even when you know where to look, finding fossils isn’t easy.

Judd’s team built quarries in areas where they expected to find fossils.

View Larger
Image|Judd Case/East Washington University
When they found fossil deposits, the team would build a quarry

“You’re on your knees in the quarry to find these larger bones,” says Judd. “But most of the fossils are fragments of skull or teeth. You need to sieve through them with water.”

With not enough water to sift all the dirt and rock, the team ended up bringing kilos of potential fossils back to Adelaide.

“It’s the last, most tedious part of the process to pick through that,” says Judd. “You sort through grain by grain, picking out any bone that’s there.”

Each excavated rock layer can represent millions of years. Over these massive timespans, the climate changed many times. These changes caused some species to go extinct and slowly moulded Australia’s modern-day marsupial species.

“The fossils show changes in climate really shaped the modern bandicoots,” says Judd.

“It was the combination of many climate changes that caused multiple extinction events.”

*Feature image full credit: Sheepbaa, Public domain, via Wikimedia Commons

Particle Puns


Creative Commons Logo

Republishing our content

We want our stories to be shared and seen by as many people as possible.

Therefore, unless it says otherwise, copyright on the stories on Particle belongs to Scitech and they are published under a Creative Commons Attribution-NoDerivatives 4.0 International License.

This allows you to republish our articles online or in print for free. You just need to credit us and link to us, and you can’t edit our material or sell it separately.

Using the ‘republish’ button on our website is the easiest way to meet our guidelines.


You cannot edit the article.

When republishing, you have to credit our authors, ideally in the byline. You have to credit Particle with a link back to the original publication on Particle.

If you’re republishing online, you must use our pageview counter, link to us and include links from our story. Our page view counter is a small pixel-ping (invisible to the eye) that allows us to know when our content is republished. It’s a condition of our guidelines that you include our counter. If you use the ‘republish’ then you’ll capture our page counter.

If you’re republishing in print, please email us to let us so we know about it (we get very proud to see our work republished) and you must include the Particle logo next to the credits. Download logo here.

If you wish to republish all our stories, please contact us directly to discuss this opportunity.


Most of the images used on Particle are copyright of the photographer who made them.

It is your responsibility to confirm that you’re licensed to republish images in our articles.


All Particle videos can be accessed through YouTube under the Standard YouTube Licence.

The Standard YouTube licence

  1. This licence is ‘All Rights Reserved’, granting provisions for YouTube to display the content, and YouTube’s visitors to stream the content. This means that the content may be streamed from YouTube but specifically forbids downloading, adaptation, and redistribution, except where otherwise licensed. When uploading your content to YouTube it will automatically use the Standard YouTube licence. You can check this by clicking on Advanced Settings and looking at the dropdown box ‘License and rights ownership’.
  2. When a user is uploading a video he has license options that he can choose from. The first option is “standard YouTube License” which means that you grant the broadcasting rights to YouTube. This essentially means that your video can only be accessed from YouTube for watching purpose and cannot be reproduced or distributed in any other form without your consent.


For more information about using our content, email us:

Copy this HTML into your CMS
Press Ctrl+C to copy

We've got chemistry. Want something physical?