A giant marsupial that roamed prehistoric Australia 25 million years ago is so different from its womb cousins that scientists have had to create a new family to welcome it.
The unique remains of a prehistoric and gigantic marsupial similar to a wombat ̵
Mukupirna – which means “big bones” in the Aboriginal languages Dieri and Malyangapa – is described in a document published June 25, 2020 in Scientific reports by an international team of paleontologists including researchers from UNSW in Sydney, Salford University in the United Kingdom, Griffith University in Brisbane, the Museum of Natural History in London and the American Museum of Natural History in New York. The researchers reveal that the partial skull and most of the skeleton originally discovered in 1973 belonged to an animal more than four times the size of any living wombat today and may have weighed about 150 kg.
An analysis of MukupirnaEvolutionary reports reveal that although it was closely related to wombats, it is so different from all known wombats and other marsupials that it had to be placed in its only family, the Mukupirnidae.
UNSW Science professor Mike Archer, co-author of the document, was part of the international international team of paleontologists along with Professor Dick Tedford, another co-author, who found the skeleton in 1973 on the clay bottom of Pinpa Lake – a remote, dry salt lake at east of the Flinders Ranges, in southern Australia. Their discovery says Mukupirna it was partly due to good luck after an unusual change in local conditions revealed the fossil deposit 25 million years ago on the bottom of the dry salt lake.
“It was an extremely serendipitous discovery because in most years the surface of this arid lake is covered in sands blown or wet by the surrounding hills,” he says.
“But due to the rare environmental conditions before we arrived that year, the fossil-rich clay deposits were completely exposed to view. And this unexpected vision was breathtaking.
“On the surface, and just below, we found skulls, teeth, bones and, in some cases, articulated skeletons of many new and exotic types of mammals. In addition, there were the teeth of an extinct lung fish, bone fish skeletons and the bones of many types of waterfowl including flamingos and ducks.
“These animals ranged from small carnivorous mouse-sized marsupials to Mukupirna which was similar in size to a living black bear. It was an incredibly rich fossil deposit full of extinct animals that we had never seen before. “
Professor Archer says when MukupirnaThe skeleton was first discovered just below the surface, no one had any idea what kind of animal it was because it was solidly enclosed in clay.
“We found it by probing the flat and dry surface of the lake with a thin metal pole, like acupuncture the skin of Mother Earth. We only dug down into the clay if the stake touched something hard below the surface – and in this case it turned out to be the articulated skeleton of a mysterious new creature. “
The recent study by researchers on the partial skull and skeleton reveals that, despite its bear-like size, Mukupirna he was probably a gentle giant. His teeth indicate that he only existed on plants, while his powerful limbs suggest that he was probably a strong digger. However, a careful examination of its characteristics revealed that the creature was more suitable for digging, and would probably not have been a real den like modern wombats, say the authors.
This was stated by the main author of dr. Robin Beck of the University of Salford Mukupirna it is one of the best preserved marsupials that emerged from the end of Oligocene Australia (about 25 million years ago).
“Mukupirna clearly it was an impressive and powerful beast, at least three times larger than modern wombats, ”he says. “He probably lived in an open forest environment without herbs and developed teeth that would allow him to feed on sedges, roots and tubers that he could dig with his powerful front legs.”
Griffith University associate professor Julien Louys, who co-authored the study, said that “the description of this new family adds a huge new piece to the diversity puzzle of the ancients, and often seriously strange marsupials that preceded those who govern today the continent. “
Scientists examined how body size evolved in wombatiform marsupials – the taxonomic group that includes Mukupirna, wombats, koalas and their fossil relatives – and have shown that body weights of at least 100 kg have evolved at least six times in the past 25 million years. The largest known wombat-shaped marsupial was relatively recent Diprotodon, which weighed over 2 tons and survived until at least 50,000 years ago.
“Koalas and wombats are fantastic animals,” says Dr. Beck, “but animals like it Mukupirna they show that their extinct relatives were even more extraordinary and many of them were giants. “
Reference: “A new family of Protododont marsupials from the last Oligocene of Australia and the evolution of wombat, koala and their relatives (Vombatiformes)” by Robin MD Beck, Julien Louys, Philippa Brewer, Michael Archer, Karen H. Black and Richard H. Tedford, June 25, 2020, Scientific reports.
DOI: 10.1038 / s41598-020-66425-8
The original party that discovered Mukupirna in 1973 was an international exploration team led by Professor Dick Tedford of the American Museum of Natural History together with paleontologists from the South Australian Museum (Neville Pledge), Queensland Museum (where Professor Archer was a fossil curator and modern Mammals at the moment), Flinders University (Professor Rod Wells) and Australian Geological Survey Organization (Mike Plane and Richard Brown).