An illustration of Repenomamus robustus, a mammal, attacking the plant-eating dinosaur Psittacosaurus lujiatunensis moments earlier than a volcanic particles move buried them each, about 125 million years in the past in China.
| Photo Credit: Michael W. Skrepnick/Reuters
While there’s little doubt that many a Mesozoic mammal turned a meal for a dinosaur, it might come as a shock to be taught that some mammals additionally dined on dinos.
A dramatic fossil unearthed in northeastern China shows a badger-like mammal within the act of attacking a plant-eating dinosaur, mounting its prey and sinking its tooth into its sufferer’s ribs about 125 million years in the past, scientists mentioned on July 18.
Dated to the Cretaceous Period, it shows the four-legged mammal, Repenomamus robustus – the dimensions of a home cat – ferociously entangled with the beaked two-legged dinosaur Psittacosaurus lujiatunensis, as massive as a medium-sized canine. The scientists suspect they have been abruptly engulfed in a volcanic mudflow and buried alive.
“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 palaeobiologist Jordan Mallon of the Canadian Museum of Nature in Ottawa, who helped lead the research 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 added.
Most mammals in the course of the Mesozoic Era, the age of dinosaurs, have been shrew-sized bit gamers within the bigger theater of life, doing properly to keep away from changing into another person’s lunch. Repenomamus shows no less than some mammals gave nearly 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 just about full fossil was discovered is named the “Chinese Pompeii” owing to numerous fossils of animals buried in volcanic eruptions.
Examining the fossil was like a criminal offense scene evaluation. Repenomamus is perched atop the inclined Psittacosaurus, gripping the jaw and hind leg whereas biting into the ribcage. Repenomamus measures 47 cm lengthy. Psittacosaurus is 120 cm lengthy. Both are regarded as 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 palaeontologist and research co-author Xiao-chun Wu.
It is uncommon to search out fossils exhibiting animals interacting. Another fossil discovered within the Nineteen Seventies in Mongolia shows two dinosaurs, predator Velociraptor and plant-eater Protoceratops, combating about 80 million years in the past earlier than being buried alive, maybe in a collapsing sand dune.
