An unusual new species of giant kangaroo has been discovered in Australia and New Guinea

Flinders University researchers have identified three new species Giant fossil kangaroos from Australia and New Guinea reveal more diversity in their shape, geographic distribution, and movement than previously thought.

Three new species belong to extinct species Protemnodon, It lived about 5 million to 40,000 years ago—an individual roughly twice the size of the largest red kangaroo alive today.

The research follows the discovery of several complete fossilized skeletons of kangaroos from Lake Kalabona in arid South Australia in 2013, 2018 and 2019. These unusual fossils enabled lead researcher Dr. Isaac Kerr, then a PhD student, to discover the nearly 150-year-old skeleton. The puzzle surrounds the identity of species Protemnodon.

Diversity among Protemnodon species

New Flinders University The study examined all categories Protemnodon, found them to be very different from each other. Species have evolved in different ways to adapt to different environments. Protemnodon A gray resembles a kangaroo, but is generally more mobile and muscular. Some species weigh around 50 kg, while others are much larger than a living kangaroo.

However, a new species – named as part of a recent study – has been named Viator Protemnodon – Very large, weighing up to 170 kg. This is twice the size of the largest male red kangaroos.

Viator Protemnodon It was well adapted to its arid habitat in central Australia, living in areas similar to present-day red kangaroos. It is a long-limbed kangaroo that can jump very quickly and efficiently. Its name, Viator, is Latin for “traveler” or “traveler.” Australian researchers have also discovered two new species: Protemnodon mamgurra And Protemnodon tawsonae – While revisiting the work of earlier researchers, including British naturalist Sir Richard Owen, who coined the term “dinosaur” in Victorian England.

The first species Protemnodon Described by the British paleontologist Owen in 1874, he followed the general approach of the time, focusing primarily on fossil teeth. He noted slight differences between the teeth of his specimens and described six types Protemnodon. Subsequent studies have dismissed some of these initial explanations, but a new study from Flinders University acknowledges one of its species, Protemnodon anak. The first described specimen, known as the holotype, is still in the Natural History Museum in London.

According to Dr. Kerr, it was previously recommended that all or part of Protemnodon were quadrupled. “However, our study suggests that this is true for only three or four species Protemnodon, It may have moved like a quacka or poturo—sometimes hopping on all fours, other times on two.

“Describes the new Protemnodon mamgurra Maybe one of them. A large but sturdy and thick-boned kangaroo, it can be very slow and inefficient. If he was startled, he would hardly have jumped.

The discovery of the largest known skeleton of Protemnodon viator, a specimen nicknamed “Old Greg” due to its large size and badly worn teeth, indicates an advanced age. A partial skeleton of Diprotodon, an extinct giant marsupial, is in the foreground. The location is the town of Tedford on Lake Calabona, northeast of the Flinders Ranges in South Australia. Credit: Aaron B Camens, Flinders University (September 2018)

Dr Kerr says the best fossils of this species come from Green Waterhole Cave in south-eastern South Australia, on the lands of the Pontic people. The species name Mamgurra was chosen by Pontic elders and linguists in the Purantis Corporation. It means “big kangaroo”.

He says it is unusual for one species of kangaroo to live in such a diverse environment. “For example, different races Protemnodon It is now known to inhabit a wide range of habitats, from arid central Australia to the forests of Tasmania and New Guinea, to the high rainfall mountains.

The third of the new species, Protemnodon dawsonae, is known from fewer fossils than the other two and is more mysterious. It is often a medium-speed jumper, similar to the swamp wallaby. It is named after the research work of Australian paleontologist Dr Lyndall Dawson, who studied kangaroo structure and fossil material from the “Big Sink”, part of the Wellington Caves in New South Wales, where the species is mainly known.

Implications of the study

To collect data for the study, Dr. Kerr visited the collections of 14 museums in four countries and examined “every piece of art”. Protemnodon is there. »

“We photographed and 3D scanned over 800 specimens collected from across Australia and New Guinea, took measurements and compared and described them. It was quite an effort. After five years of research, 261 pages and more than 100,000 words, it feels great to finally put it out into the world. I hope this will help further studies Protemnodon will happen, so we can learn more about what these kangaroos were doing. Living kangaroos are already remarkable animals, so it's amazing to think what these particular giant kangaroos could have done.

Paleontologist Isaac Kerr shows the fossilized jaw of the giant kangaroo Protemnodon viator and the much smaller jaw of the largest living kangaroo, the red kangaroo. Credit: Flinders University

when Protemnodon Fossils are very common across Australia, historically found as “isolated” or individual bones without other animals. This hampers the study of paleontologists Protemnodon In the past, it was difficult to tell how many species there were, how to tell them apart—and how species differed in size, geographic distribution, movement, and adaptation to their natural environment.

About 40,000 years ago, everything Protemnodon Extinct from the Australian continent, perhaps persisting for a little longer in New Guinea and Tasmania. This extinction occurred despite differences in their size, adaptations, habitat and geographical distribution.

For reasons still unknown, this does not happen to many similar and closely related animals, such as wallaroos and gray kangaroos. This question may soon be answered by further research, partly aided by this study.

“It would be great to have some clarity on the identity of race Protemnodon” says Flinders Professor Gavin Prideaux, co-author of the major new paper Megataxa. Fossils of this species are widely and regularly found, but often, you have no way of knowing which species you're looking at. This study will help you be more confident when working with researchers Protemnodon.”

This study was supported by grants from the Australian Research Council and Flinders University and the Australia and Pacific Science Foundation and the Royal Society of South Australia.