Oldest evidence of 'generalist carnivorous dinosaurs' found in fossils suggesting dinosaurs ate mammals

Small mammals that are human ancestors have existed since dinosaurs lived on the earth, and some dinosaurs may have preyed on mammals. Newly, 'evidence that dinosaurs ate mammals' was discovered from the fossils of

https://doi.org/10.1080/02724634.2022.2144337

The other paleo diet: Rare discovery of dinosaur remains preserved with its last meal - McGill University
https://www.mcgill.ca/newsroom/channels/news/other-paleo-diet-rare-discovery-dinosaur-remains-preserved-its-last-meal-344495

Scientists find the earliest evidence of a dinosaur eating a mammal | Live Science
https://www.livescience.com/microraptor-rodent-foot-meal-china

Rare Dinosaur Fossil Found With Perfectly Preserved Final Meal Inside : ScienceAlert
https://www.sciencealert.com/rare-dinosaur-fossil-found-with-perfectly-preserved-final-meal-inside

Microraptor is a small feathered dinosaur that lived in the early Cretaceous period (about 145 million to 105 million years ago), and fossils have been excavated in Liaoning Province , China. It is about the size of a modern crow and is characterized by well-developed flight feathers on both its front and hind legs. Previous research suggests that Microraptor could use its wings to glide through the air, jumping from trees and preying on small animals.

Hans Larsson , a vertebrate paleontologist and director of the Redpath Museum at McGill University in Canada, was investigating a private collection housed in a Chinese museum when he discovered that a Microraptor fossil had a thorax. found to contain 'fossilized mammalian feet'. The following picture is the fossil of Microraptor investigated by Larson et al.'s research team, and the fossil of the predated mammal was in the part surrounded by the yellow border.

This is a close-up picture of a mammalian fossil. Foot fossils are included in the part surrounded by a red frame.

Looking at the color-coded diagrams of the research team, you can clearly see which part is the mammal's foot. The fossils found are about 1 cm long and are believed to be small rodents.

'I couldn't believe it at first,' Larsen said. 'The find is the only solid evidence of food consumption in a long-extinct animal, and it's extremely rare.'

In the past, 20 cases have been reported in which ``fossils of the last prey'' were discovered from the fossils of carnivorous dinosaurs, and among them, Microraptor preyed on fish, birds, lizards, etc. It is said that the fossils shown are also included. However, this fossil is the first to show that Microraptor ate mammals.

The discovery that Microraptor preyed on mammals in addition to fish, birds, and lizards shows that Microraptor's diet was very diverse. Like modern foxes and crows, ``generalist carnivores'', which have a variety of diets, function as ``ecosystem stabilizers'' because they can change the target of predation according to the number of individuals.

According to the research team, this fossil may be the oldest evidence of the existence of a ``generalist carnivore''. 'Finding out that Microraptor was a generalist carnivore has given us a new perspective on how ancient ecosystems worked, and helped us learn more about the success of small, feathered dinosaurs,' Larson said. I can,' he said.