Mammal and dinosaur found locked in combat at ‘China’s dinosaur Pompeii’ | 24CA News

A badger-like mammal died whereas chomping into the ribs of a hapless horned plant-eating dinosaur struggling to flee greater than 100 million years in the past. The pair had been completely preserved, nonetheless locked in fight, in “China’s dinosaur Pompeii,” researchers report.

Dating to the Cretaceous Period, the dramatic fossil unearthed in northeastern China reveals the four-legged mammal Repenomamus robustus — the dimensions of a home cat — ferociously entangled with the beaked two-legged dinosaur Psittacosaurus lujiatunensis, as huge as a medium-sized canine.

Scientists suspect they had been all of a sudden engulfed in a volcanic mudflow and buried alive throughout mortal fight.

“Dinosaurs nearly always outsized their mammal contemporaries, so traditional belief has been that their interactions were unilateral — the bigger dinosaurs always ate the smaller mammals,” mentioned paleobiologist Jordan Mallon of the Canadian Museum of Nature in Ottawa, who helped lead the examine revealed within the journal Scientific Reports.

“Here, we have good evidence for a smaller mammal preying on a larger dinosaur, which is not something we would have guessed without this fossil,” Mallon mentioned.

A posh meals internet

Most mammals throughout the Mesozoic Era, the age of dinosaurs, had been shrew-sized bit gamers within the bigger theatre of life, doing nicely to keep away from turning into another person’s lunch. Repenomamus reveals that a minimum of some mammals gave pretty much as good as they bought.

“I think what’s key here is that Mesozoic food webs were more complex than we had imagined,” Mallon mentioned.

The space in Liaoning Province the place the nearly full fossil was discovered is known as the “Chinese Pompeii,” owing to numerous fossils of animals buried in volcanic eruptions.

Examining the fossil was like against the law scene evaluation. Repenomamus is perched atop the susceptible Psittacosaurus, gripping the jaw and hind leg whereas biting into the ribcage. Repenomamus measures 47 centimetres (18 inches) lengthy. Psittacosaurus is 120 centimetres (4 ft) lengthy. Both are considered not fairly full adults.

“There have been specimens of carnivorous dinosaurs preying on plant-eating dinosaurs before, but there has never been an example of a mammal preying on a dinosaur,” mentioned Canadian Museum of Nature paleontologist and examine co-author Xiao-Chun Wu.

Preserved in battle

It is uncommon to seek out fossils displaying animals interacting. Another fossil discovered within the Seventies in Mongolia reveals two dinosaurs — predator Velociraptor and plant-eater Protoceratops — preventing about 80 million years in the past earlier than being buried alive, maybe in a collapsing sand dune.

The researchers discounted the concept that the Repenomamus and Psittacosaurus fossil confirmed a mammal merely scavenging a carcass.

“For one, the mammal is on top of the dinosaur as though it was trying to subdue it, which the scavenging hypothesis doesn’t account for,” Mallon mentioned.

“Second, there are no bite marks on the bones of the dinosaur, which we would expect if it had been sitting out for long, exposed to scavengers. Lastly, the hind foot of the mammal is trapped by the folded hind leg of the dinosaur, which is unlikely to have happened if the dinosaur had already been dead when the mammal came across it,” he mentioned.

While Psittacosaurus was an early relative of the horned dinosaur lineage, it lacked facial horns and a head crest. It possessed a parrot-like beak to crop plant materials.

Repenomamus, one of many dinosaur age’s largest mammals, had quick and sprawling limbs, an extended tail, a sinuous physique, a strong cranium and shearing enamel. Mallon in contrast its look to the dwelling Chinese ferret-badger.

There was earlier proof of the dino-eating habits of Repenomamus. One Repenomamus fossil from the identical space had child Psittacosaurus bones in its abdomen.

“What’s unique about our fossil is the fact that it demonstrates that Repenomamus was capable of tackling larger dinosaur prey,” Mallon mentioned.