The fossil shows a badger-like creature devouring a small dinosaur with its beak, its skeletons intertwined. The discovery comes from a site known as “Chinese Pompeii,” where mud and debris from ancient volcanoes buried the creatures in their place.
“This appears to be a prehistoric haunt, captured in stone, like a frozen image,” University of Edinburgh paleontologist Steve Brusatte, who was not involved in the study, said in an email.
The fossil described Tuesday in the paper Scientific reportsshows two creatures dating from about 125 million years ago, during the Cretaceous period.
Although the mammals were much smaller, researchers believe they were attacking the tyrannosaurus when they were trapped in the volcanic flow, according to study author Jordan Mallon, a paleobiologist at the Canadian Museum of Nature. The mammal perched on top of the tyrannosaurus, its paws grasping the reptile’s jaw and hind limbs while its teeth sank into its ribcage.
“I’ve never seen a fossil like this before,” Mallon said.
It had previously been suggested that mammals ate dinosaur meat: another fossil showed a dead mammal with the remains of a dinosaur in its stomach.
Mallon explained that this new discovery also indicates that mammals could hunt dinosaurs many times their size and not only feed on dinosaurs that have already died.
“It disturbs the old story,” Brusatte said. “We used to think of the age of dinosaurs as a time when dinosaurs ruled the world and small mammals lurked in the shadows.”
The study authors acknowledged that there were few known pseudo-fossil finds in this region of the world, which Mallon said was a concern when they began their research. But after preparing the skeletons themselves and analyzing rock samples, he said they were confident the fossil — unearthed by a farmer in 2012 — was authentic and would welcome other scientists to study the fossil as well.
The mammal in the fossil duo, Malone said, is the domestic cat-sized, meat-eating Repinomamus robustus. The dinosaur – Psittacosaurus lujiatunensis – was the size of a medium-sized dog with a parrot-like beak.
This type was a herbivore, but other dinosaurs were carnivores or ate both. Ultimately, Mallon said, dinosaurs probably ate more mammals than the other way around.
“However, we now know that mammals were able to fight back, at least sometimes,” he added.
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