The surprising lunch of a cat-sized dinosaur has been discovered in a 120-million-year-old Microraptor fossil. thought the fossil was first described in 2000hid an intriguing and historical secret: a new analysis of the fossil found the bones of a mammal’s foot inside the raptor’s ribcage, the first evidence of a dinosaur eating a mammal.
the find, described in the Journal of Vertebrate Paleontology on Tuesdayis based on previous research of the Microraptor zhaoianus fossil, discovered in the Jiufotang Formation in western China. That fossil is missing the middle part of its body, but the ribcage is visible, and inside, the bones of a tiny right foot, less than half an inch in size, were perfectly preserved.
Microraptors were three-toed carnivorous dinosaurs that inhabited the trees of ancient Earth and are among the smallest dinosaurs ever discovered. Fossils of different species of microraptor show evidence of long feathers on each limb, which may have been used for gliding.
Unsurprisingly, being eaten doesn’t usually result in very well-preserved fossil remains. All that biting and chewing, plus digestion, usually leaves little trace of a meal. However, scientists have a pretty good idea of the microraptor’s diet thanks to fossils with undigested remains in their stomachs.
A bird, a fish and a squamate, the class of animals that contain lizards and snakes, have all been found previously, but the new find helps paint a more complete picture of what went down the gorge during a prehistoric tasting.
“It’s very rare to find examples of food inside dinosaurs, so each example is really important as it provides direct evidence of what they were eating,” said David Hone, a paleontologist at Queen Mary University of London and first author of the paper. new study.
While scientists can say one foot ended up in the microraptor’s stomach, they aren’t sure which species it belonged to. The slender digits are similar to the small extinct opossum-like mammals known as synodelfis or the most similar to a mouse Eomaia. However, the digits are not long enough to be from any of these species.
Another remaining question is whether Microraptor preyed on the mammal or simply stole the foot. That’s impossible to say with this fossil, but some scientists have suggested that the microraptor’s feathered limbs may have allowed the species to slither from branches to the ground to hunt terrestrial species. The size of the mammal’s foot suggests that the creature would have been in the size range expected for microraptor prey.
The amazing fossil builds on previous evidence that these smaller, three-toed dinosaurs would feast on whatever was around them; they may even have eaten plants on occasion.