by A version of the mythical Australian “drop bear,” a carnivorous marsupial similar to a koala, actually lived on the continent until at least about 40,000 years ago, scientists revealed in a new study.
The “drop bear” is a classic Australian myth about a carnivorous version of the koala that is said to live in trees and attack people by dropping on their heads from above.
In contrast to the docile koalas, the mythical drop bears are described in Australian folklore as unusually large and vicious marsupials.
Now researchers have found fossil evidence that a carnivorous marsupial that resembled koalas actually lived on the continent until their extinction 40,000 years ago.
Today’s koalas are the closest living relatives of this “marsupial lion.” Thylacoleo carnifex, according to a new study published in the journal Proceedings of the Royal Society B.
These carnivorous marsupials thrived on the continent during the late Pleistocene period from about 126,000 years ago until one of the largest waves of large animal extinctions on the planet about 40,000 years ago.
A large proportion of the planet’s giant animals were lost during this time, with Australia losing almost 90 percent of its land species weighing over 44 kg around 46,000 years ago.
Thylacoleo carnifex sculpture in the Australian Museum (Australian Museum/Wikimedia Commons)
This period, which also coincided with the arrival of humans on the continent, severely affected Australia’s biodiversity and represented a major loss in evolutionary history.
However, the causes of this mega-extinction are still poorly understood.
In the latest study, scientists used a new technique that creates a unique fingerprint for species based on the collagen proteins in their fossils.
Using this method, researchers were able to trace the evolutionary history of three extinct Australian giant animals: Zygomaturus – a herbivore that looked like a 500 kg wombat, Palorchestes – another herbivore that resembled a tapir, and Thylacoleo carnifex – the marsupial lion.
The analysis showed that the Thylacoleo is more closely related to the koala than to any other group of animals.
“The strength of the collagen peptide data suggested a close relationship between Thylacoleo (the so-called “marsupial lion”) and the koala as part of a larger group that also includes wombats,” the researchers wrote.
These results also suggest the usefulness of the new technique of using collagen protein from fossil samples to construct evolutionary trees and better understand the diversity of past life on Earth, scientists say.
The researchers hope that further research using their new method can finally clarify the cause of the mass extinction.
