A 120-million-year-old dinosaur fossil hid a surprise meal in its stomach

A cat-sized dinosaur’s surprise lunch has been discovered in a 120-million-year-old Microraptor fossil. anyway The fossil was first described in 2000it hid an interesting historical secret: A re-analysis of the fossil found a mammal’s foot bones inside the thorax of a raptor—the first evidence of a dinosaur eating a mammal.

finding, Described in the Journal of Vertebrate Paleontology on Tuesdaybased on the previous research of Microraptor zhaoianus Fossil discovered in the Jiufotang Formation in western China. This fossil is missing the midsection of its body, but its thorax is visible, and within it, the bones of a small right foot, less than half an inch in size, are perfectly preserved.

Microraptors were three-toed, carnivorous dinosaurs that occupied the Earth’s ancient trees and are among the smallest dinosaurs ever discovered. Fossils of various species of Microraptor show evidence of long feathers on each limb, which may have been used for gliding.

As you might expect, eating food doesn’t usually yield well-preserved fossil remains. All that biting and chewing, plus digestion, usually leaves little traces of the meal. However, scientists do have a fairly good idea of ​​Microraptor’s diet thanks to fossils with undigested remains in their stomachs.

Bird, fish, and egrets—the class of animals that includes lizards and snakes—were previously found, but the new discovery helps paint a more complete picture of what was going on in the esophagus during prehistory.

“It’s very rare to find examples of food inside dinosaurs, so every example is really important because it gives direct evidence of what they ate,” said David Hone, a paleontologist at Queen Mary University of London and first author of the new study.

While scientists can tell that the foot ended up in Microraptor’s stomach, they aren’t sure what species it belonged to. The slender figures resemble the small, extinct, possum-like mammals known as possums Synodlvis or more mouse-like Yumaya. However, the numbers are not long enough to be either of those two types.

The other outstanding question is whether Microraptor preyed on mammals or if it was just a scraper. It’s impossible to say with this fossil, but some scientists have suggested that Microraptor’s feathered limbs may have allowed the species to slip from branches onto the ground to prey on land-dwelling species. The size of the mammal’s foot indicates that the creature was in the size range expected for Microraptor’s prey.

The startling fossil builds on earlier evidence that these smaller, three-toed dinosaurs would have fed on whatever was around – it’s even possible that they ate plants at times.