Did Dinosaurs Eat Mammals? Yes

At last, there’s peer-reviewed evidence to back up a pop-culture nightmare. Did dinosaurs eat mammals? In fact, yes.

But don’t get an image of a Neanderthal skeleton inside a fossilized T-Rex’s belly. Groundbreaking as it may be, the news revolves around far smaller creatures.

A team of paleontologists found the partially digested foot of what appears to be a mouse-sized animal inside the rib cage of a small feathered dinosaur known as a microraptor.

The paleontologists published their findings in the October 2021 edition of the Journal of Vertebrate Paleontology. They constitute “[the] first record of a dinosaur eating a mammal.”

Dr. David Hone of London’s Queen Mary University is the first author listed on the study. He framed his comments about the discovery in the context of ancient humans.

“While this mammal would absolutely not have been a human ancestor, we can look back at some of our ancient relatives being a meal for hungry dinosaurs,” Hone said, according to The Guardian. “This study paints a picture of a fascinating moment in time — the first record of a dinosaur eating a mammal — even if it isn’t quite as frightening as anything in Jurassic Park.”

What’s a ‘microraptor’?

If you can picture a feathered predatory dinosaur shaped like a raptor, but about the size of a turkey, you’ve got a microraptor. According to the British Natural History Museum, the animals lived in the Early Cretaceous Period, about 125-122 million years ago. It ran on two hind legs, grew to about 0.8 metres in length, and weighed around a kilogram.


Microraptor, artist’s rendering. Image: British Natural History Museum.


Microraptors fed on other small animals and insects with their small, sharp, pointed teeth. One bizarre-looking species had long “flight feathers” on all four limbs, the museum said, which may have given it the ability of guided flight.

The team’s analysis of the digested foot inside the specimen suggested its mouse-sized mammalian prey lived on the ground. Compared to other similarly sized arboreal dwellers alive at the time, this animal likely had different habits.

did dinosaurs eat mammals

Diagram of the fossilized microraptor’s gut contents. Image: David W. E. Hone, T. Alexander Dececchi, Corwin Sullivan, Xu Xing & Hans C. E. Larsson


And while the discovery is the first of its kind, it’s not the first time researchers have found a preserved microraptor with food in its stomach. Previously, scientists have found microraptor fossils containing non-mammalian prey, such as a bird, lizard, or fish.

Sam Anderson

Sam Anderson takes any writing assignments he can talk his way into while intermittently traveling the American West and Mexico in search of margaritas — er, adventure. He parlayed a decade of roving trade work into a life of fair-weather rock climbing and truck dwelling before (to his parents’ evident relief) finding a way to put his BA in English to use. Sam loves animals, sleeping outdoors, campfire refreshments and a good story.