The first proof of a dinosaur devouring a mammal has been discovered by scientists.

 A raptor the size of a crow devoured a mammal for its final supper some 120 million years ago. A recent study indicates that when studying the fossilised bones of the Microraptor, a bird-like predatory dinosaur from China, researchers discovered its last meal.

The foot of a tiny animal, most likely a rat, lying inside the little theropod's rib cage was discovered in the well-preserved fossil of the Microraptor zhaoianus, according to a release

In their paper, which was released on December 20 in the Journal of Vertebrate Paleontology, the researchers said that the discovery represents the oldest known instance of a dinosaur devouring a mammal.

Hans Larsson, director of the Redpath Museum and a vertebrate palaeontologist at McGill University in Montreal, who is a research co-author, stated in a release, "At first, I couldn't believe it. These discoveries, which are incredibly uncommon, are the only reliable proof we have regarding the diet of these long-extinct species.

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According to the statement, there were previously just 20 instances of fossilised bones that included a carnivorous dinosaur's last meal. The bone of the Daurlong wangi, a raptor species also found in China, was among them. Its intestines was described as having "a huge, blue coating in the belly." Only four documented examples (not counting this one) of stomach contents from a Microraptor itself have been found among the 20 cases studied by experts.

According to the researchers, the latest find is also just the second instance of direct proof that theropods, a group of bipedal, primarily meat-eating dinosaurs that includes Tyrannosaurus rex, consumed mammals.

This Microraptor, whose name translates to "little plunderer," was discovered in the Jiufotang Formation of Liaoning province in northeastern China. Although the precise dates of Jiufotang are uncertain, a 2000 research that first reported the fossil in the journal Nature(opens in new tab)found that it contains fossils from the early Cretaceous era (145 million to 100.5 million years ago).

In their stomachs, preserved Microraptor specimens have been found containing pieces of fish, birds, and lizards, according to Larsson. The addition of a small animal to their diet by this latest discovery "indicates that these dinosaurs were opportunistic and not discriminating eaters."