Round 120 million years in the past, four-winged dinosaurs roughly the dimensions of crows referred to as Microraptors stalked the traditional woodlands of what’s now China.
Whereas researchers have studied a number of Microraptor specimens, there’s nonetheless rather a lot we do not learn about these feathered bird-like creatures – together with what and the way they ate.
Now an extremely uncommon fossil has revealed the preserved closing meal of 1 particular person: and unexpectedly, it was a mammal.
“At first, I could not imagine it,” says vertebrate paleontologist Hans Larsson from McGill College in Canada, who discovered the fossil whereas trying by means of samples at museum collections in China.
“There was a tiny rodent-like mammal foot a few centimeter lengthy completely preserved inside a Microraptor skeleton.”
“These finds are the one strong proof we have now concerning the meals consumption of those lengthy extinct animals – and they’re exceptionally uncommon,” Larsson adds.
The primary Microraptor fossil was found in Liaoning, China, in 2000. There are three identified species, which lived within the early Cretacious interval, and the fossil in query belongs to Microraptor zhaoianus.
The Microraptors had been amongst a number of the first dinosaurs that had been discovered with absolutely feathered wings on each its legs and arms – and alongside the well-known feathered dinosaur Archaeopteryx, have strengthened theories that suggest trendy birds are carefully associated to classes of dinosaur.
While some studies have proven that Microraptors would have been able to powered flight, it is typically thought that they largely used their wings to glide.
Up till now, the small dinosaurs had solely been confirmed to eat birds, fish, and lizards, they usually had been regarded as arboreal hunters that glided down from the bushes to seize prey.
The newest discovery expands on that concept, suggesting they had been extra more likely to be opportunistic eaters that each scavenged and preyed upon quite a lot of vertebrates.
“We already know of Microraptor specimens preserved with elements of fish, a chicken, and a lizard of their bellies. This new discover provides a small mammal to their food regimen, suggesting these dinosaurs had been opportunistic and never choosy eaters,” says Larsson.
That is a giant deal, as a result of though generalist carnivores are widespread and necessary stabilizers in right now’s ecosystems – consider foxes and crows – this might very nicely be the primary proof of a generalist carnivores in a dinosaur ecosystem, Larsson and his team write.
It is extremely uncommon to seek out dinosaur fossils that protect their final meal inside their abdomen, they add. Out of all of the carnivorous dinosaur fossils which have been discovered, we solely know of 20 that comprise their final meals.
The newest discovery takes that number to 21.
Understanding extra about their diets is not simply fascinating for these of us making an attempt to think about how the world appeared 120 million years in the past, it additionally supplies necessary clues for the researchers working onerous to know precisely how dinosaurs left the land for the sky, and developed into the true birds we see right now.
“Figuring out that Microraptor was a generalist carnivore places a brand new perspective on how historical ecosystems could have labored and a doable perception into the success of those small, feathered dinosaurs,” says Larsson.
The analysis has been printed in The Journal of Vertebrate Paleontology.