Ancient Creature Unveiled as a Predator of Dinosaurs: Revealed by ScienceAlert

**Unlikely Predator: Mammal Feasts on Dinosaur in the Cretaceous World**

*Psittacosaurus and Repenomamus: An Unusual Predation*
The Cretaceous world was a dangerous place, where life struggled to survive amidst constant danger. Recent evidence has revealed a surprising predation event involving a dinosaur and an unexpected predator. The fossilized remains of Psittacosaurus lujiatunensis, a dinosaur species, were discovered with its rib cage held in the mouth of a much smaller predator. This predator turned out to be Repenomamus robustus, an opossum-like mammal. What makes this discovery remarkable is that it provides the first evidence of predatory behavior by a mammal on a dinosaur.

**The Noteworthy Fossil**
A fascinating fossil was unearthed, depicting the entangled bodies of the mammal and the dinosaur, frozen in a deadly embrace. This fossil paints a vivid picture of the ferocious battle that took place millions of years ago. It signifies the coexistence of these two creatures, shedding light on their complex relationship and adding to our understanding of the Cretaceous world.

**Psittacosaurus: A Powerful Dinosaur**
Psittacosaurus, a genus of dinosaurs, existed between 125 and 101 million years ago, thriving across Asia, Russia, Mongolia, and Thailand. These dinosaurs possessed parrot-like beaks, walked on their hind legs, and had clawed forelimbs. Growing up to approximately 2 meters in length, these creatures were formidable predators in their own right.

**Repenomamus: The Ancient Mammal**
Repenomamus robustus belonged to the Repenomamus species that lived during the early Cretaceous period. Although smaller than its contemporary counterparts, it was still considered one of the largest mammals of its time. The age of dinosaurs was dominant during this period, leaving mammals as a minority in the diverse ecosystem.

**Understanding the Predatory Dynamics**
Initially, it was believed that the Repenomamus robustus was merely scavenging on the remains of a deceased Psittacosaurus. After careful examination, experts discovered that this assumption was incorrect. The arrangement of the bones and the absence of characteristic scavenging bite marks indicated that an active attack had taken place. The mammal’s position on top of the dinosaur suggested its role as the predator rather than a scavenger.

**Unusual Predators in the Animal Kingdom**
In the modern world, smaller predators sometimes overcome larger prey through their aggression and tenacity. The fossilized evidence of Repenomamus attacking a larger dinosaur aligns with such occurrences. Examples from today’s animal kingdom, such as packs of lions and wolves, demonstrate how smaller animals can coordinate to bring down larger prey. Moreover, solitary predators like wolverines and honey badgers have been known to tackle prey much larger in size. This fierce instinct for survival could potentially have been an early trait of Repenomamus, leading it to prey on dinosaurs like Psittacosaurus.

**The Enduring Story**
Millions of years after their demise, the fossilized remains of these entangled creatures tell a compelling story. It offers a glimpse into the perilous existence of life during the Cretaceous period, where every creature fought to survive. The extraordinary fossil of Psittacosaurus and Repenomamus immortalizes an unlikely predator-prey relationship, leaving a lasting legacy for paleontologists to study and piece together.

**The Remarkable Findings**
The findings of this groundbreaking research have been published in Scientific Reports, unveiling the incredible world of the Cretaceous era. The discovery of a mammal preying on a dinosaur highlights the intricate interplay between different species during this time. This fossilized evidence provides a significant contribution to our understanding of the predator-prey dynamics in prehistoric times.