by A newly discovered ancestor of the extinct Tasmanian tiger had “extremely thick” jawbones that allowed it to crush its prey, including bones and teeth.
This is the result of a new study published on Saturday in Journal of Vertebrate Paleontology. It describes three ancient types of modern Tasmanian Wolvescommonly known as the Tasmanian tiger, which became extinct 88 years ago.
The research results were published on the occasion of Australia’s National Threatened Species Day, which commemorates the death of the very last Tasmanian tiger on September 7, 1936.
According to the researchers, the newly discovered species are “undoubtedly the oldest representatives” of the Tasmanian tiger, which roamed Australia 23 to 25 million years ago, in the late Oligocene.
Their fossils were excavated in the Riversleigh World Heritage Site.
The study sheds new light on the ecology of the region millions of years ago and changes previous ideas.
“The idea once put forward that Australia was dominated by carnivorous reptiles during this 25 million year period is increasingly being disproved as more and more fossils of marsupial carnivores such as these new Tasmanian wolves are found with each new discovery,” said lead study author Timothy Churchill.
Scientists now believe that the diversity of carnivorous mammals in the Riversleigh area during this period is comparable to that of any other ecosystem in the world.
The largest of the newly discovered species, Badjcinus timfaulkneriweighed up to 11 kg, about as much as a large Tasmanian devil.
It had an extremely thick jawbone that allowed it to crush even the bones and teeth of its prey. This species was related to the much smaller, previously discovered B turnbullithe only other Tasmanian wolf known from this period.
Another species found in recent excavations is Nimbacinus peterbridgeithat was about the size of a Maltese terrier, researchers said.
The scientists identified and named the species based on nearly complete tooth fossils. They believe it was a predator that fed on small mammals and other prey that lived with it in the primeval forests.
Researchers suspect N peterbridgei could be the oldest known direct ancestor of the Tasmanian tiger.
The last of the three species identified in the new study is Ngamalacinus nigelmarveniwhich was about the size of a red fox and weighed almost 5.1 kg.
Molar fossils of this species suggest that it was heavily carnivorous, “more than any other Tasmanian wolf of similar size.”
“These Tasmanian wolves have very different dental adaptations, suggesting that there were several unique carnivorous niches during this time. All of these lineages except one, which led to the modern Tasmanian wolves, became extinct about 8 million years ago,” said study co-author Michael Archer.
“The line of these creatures, which survived for more than 25 million years, ended with the death of Benjamin, the last Tasmanian tiger at Beaumaris Zoo in Hobart, on September 7, 1936.”
