Tag Archives: wombat

Marsupial rave: wombats have glow-in-the-dark fur

Besides wombats, scientists found that many other marsupials are also biofluorescent under UV light.

Ever seen a wombat under a blacklight? Not a lot of people have, it seems — it’s only recently that scientists have found that wombat fur is actually biofluorescent, meaning it absorbs blue light and then re-emits it as the color green. The same investigation found that echidnas, possums, and other mammals are biofluorescent.

An accidental discovery revealed that marsupials must love a good rave

It was just a couple of weeks ago that American researchers at the Field Museum accidentally discovered that platypuses glow in dark/purple when UV light is shone on the peculiar mammal’s fur. Now, a new creature can join that lit club: the wombat.

Biofluorescence has long been known to occur in some insects and sea creatures, but no one really thought of verifying the pink-glowing phenomenon in mammals. Naturally, everyone was pretty amazed — and it turns out biofluorescence in mammals is a lot more common than we thought. At least among Australian marsupials.

Platypuses glow green under UV light. Credit: Mammalia.

Spurred by the serendipitous discovery of the biofluorescent platypus fur, the curators of the Western Australian Museum decided to shine UV light on some of their own museum specimens.

Much to their surprise, out of two dozen mammals in their collection, around a third of them had glowing fur. This includes the platypus, echidna, bandicoots, bilbies, possums, some bats, as well as the iconic wombat.

Most of these animals, including wombats, are either nocturnal or crepuscular (active at dawn or dusk). So perhaps the biofluorescence may improve their survivability, especially since ultraviolet light is more prevalent at dusk and dawn.

“Perhaps they are able to see much more than we are able to see,”  Kenny Travouillon, the Western Australian Museum curator of Mammalogy, told Science Alert.

“Predators don’t seem to glow. I think this is because if predators could be seen, they would lose all chance of catching their prey,” he added.

Then again, a lot of marsupials are nocturnal, so perhaps something else may explain the evolutionary drive for biofluorescence. Since these observations have been made in museum specimens on a tiny sample size, perhaps field investigations could provide more answers. In the future, researchers at the Australian Museum want to do just that with the help of different lights.

Extinct giant wombat-like marsupial the size of a black bear found in Australian desert

There are three species of wombats alive today, all perfectly adapted to Australia’s rough wilderness. Some 25 million years ago, however, the continent was roamed by a giant wombat-like marsupial, which was only recently described by scientists.

The animal was more than four times the size of any living wombats today and had some unique features deserving of its own new family of marsupials.

Mukupirna was roughly the size of a black bear and had strong teeth and powerful limbs for digging. Credit: Peter Schouten.

The newly identified ancient mammal is called Mukupirna – meaning “big bones” in the Dieri and Malyangapa Aboriginal languages.

The extinct giant creature was now described based on a partial skull and almost complete skeleton originally discovered in 1973 in the clay floor of Lake Pinpa — a remote, dry salt lake east of the Flinders Ranges in South Australia.

Mike Archer, co-author of the new study and a professor at the University of New South Wales (UNSW), was part of the team that performed the original fieldwork in the 1970s.

Like many amazing paleontological discoveries before them, Archer recounts how they came across the fossils by accident, after a fortunate change in atmospheric conditions revealed the 25 million-year-old fossil deposits on the floor of the dry lake.

“It was an extremely serendipitous discovery because in most years the surface of this dry lake is covered by sands blown or washed in from the surrounding hills,” he says.

“But because of rare environmental conditions prior to our arrival that year, the fossil-rich clay deposits were fully exposed to view. And this unexpected view was breathtaking.”

Besides the remains of Mukupirna, the paleontologists also collected a wealth of fossils belonging to other extinct ancient creatures.

“On the surface, and just below we found skulls, teeth, bones and in some cases, articulated skeletons of many new and exotic kinds of mammals. As well, there were the teeth of extinct lungfish, skeletons of bony fish and the bones of many kinds of water birds including flamingos and ducks.

“These animals ranged from tiny carnivorous marsupials about the size of a mouse right up to Mukupirna which was similar in size to a living black bear. It was an amazingly rich fossil deposit full of extinct animals that we’d never seen before.”

It took almost 50 years to properly describe Mukupirna since its fossils had been solidly encased in clay for all this time. It was only recently that Archer and collegues revisited the fossils, finding that the clay pristinely preserved the remains of a new marsupial family.

A gentle giant

Judging from its skeleton, the paleontologists estimate that Mukupirna was a very powerful beast the size of a black bear today — more than four times the size of any living wombats, weighing about 150 kilograms.

Mukupirna likely foraged in an open forest environment, where it used its powerful teeth to feed on sedges, roots, and tubers, which it would have dug out with its muscular front legs.

Given its voluminous size, Mukupirna sits on the top end of vombatiform marsupials — the taxonomic group that includes Mukupirna, as well as modern wombats, koalas, and their fossil relatives.

“Koalas and wombats are amazing animals,” Dr. Robin Beck from the University of Salford in the UK said in a statement, “but animals like Mukupirna show that their extinct relatives were even more extraordinary and many of them were giants.”

How wombats make cubed poop

The adorable wombats have a unique ability which has puzzled biologists for quite a while now: they make cubical poop.

Out of all the superpowers in the world, that seems like the strangest one. It’s so strange, in fact, that Patricia Yang, a postdoctoral fellow at the Georgia Institute of Technology, didn’t believe it at first.

“The first thing that drove me to this is that I have never seen anything this weird in biology. That was a mystery,” said Yang. “I didn’t even believe it was true at the beginning. I Googled it and saw a lot about cube-shaped wombat poop, but I was skeptical.”

Yang studies how fluids, including blood, processed food, and urine, move about inside the bodies of animals — so she was perfect for the task. She carried out an analysis of wombat digestive systems on individuals which had been euthanized following motor vehicle collisions in Tasmania, Australia.

The researchers found that near the end of the digestive system, the poop turned from liquid to solid, and that’s when it becomes a cube. The group believes that the elasticity of the wombats’ intestinal walls allow for this process to take place, and at quite a high pace — wombats typically produce 80-100 cubes per night.

Credits: P. Yang and D. Hu.

Wombats used their squared scat to stack pieces on top of each other, making them more visible as a territory marking. Because the sides are flat, they’re also less likely to roll away or be blown by the wind. However, this ability appears unique in the animal world. Although cubes and other squared surfaces are quite common in industrial and some geological processes, they’re almost inexistent in the biological world, which makes the topic much more attractive, both for researchers and the general public.

“We currently have only two methods to manufacture cubes: We mold it, or we cut it. Now we have this third method,” Yang said. “It would be a cool method to apply to the manufacturing process — how to make a cube with soft tissue instead of just molding it. We can learn from wombats and hopefully apply this novel method to our manufacturing process,” Yang said. “We can understand how to move this stuff in a very efficient way.”

Co-author Scott Carver says that public interest, as well as the unusual nature of the problem, drove this study.

“There is much general interest from the public, both in Australia and internationally, about how and why wombats create cube-shaped feces. Many ideas, some more entertaining than others, have been put forward to explain this, but until this study nobody had ever investigated the cause. This has been a fantastic collaboration which shows the value of interdisciplinary research for making new scientific discoveries.”

The study “How do wombats make cubed poo?” was presented at the Annual Meeting of the APS Division of Fluid Dynamics.