Found in the stomach of one of the smallest dinosaurs, known as “Microraptor”, the fossilized remains of a 120-million-year-old mammal.

According to CNN, Hans Larsson, a professor of biology at McGill University and an author of the study, discovered a fossilized claw of another mammal in the stomach of Microraptor, which is about one meter in size, while examining the collections of a museum in China.

They found a “perfectly preserved” small leg of a rodent-like mammal, about one centimeter long, in the stomach of the Microraptor skeleton, Larson said.

Microraptor dinosaurs ate fish, birds and lizards, Professor Larson said, but this is the first time concrete data has been found of them hunting mammals.

Larson noted that evidence of consumption of these long-extinct animals is rarely found, and said this new discovery offers a fresh perspective on ancient ecosystems.

The Microraptor fossil was first discovered in China’s Liaoning Province in the early 2000s, and is considered one of the first feathered dinosaurs to be discovered.

The research has been published in the Journal of Vertebrate Palaeontology.