Scientists have been arguing about who was the ancestor of birds for a long time. There are mainly three theories about the origin of birds: the origin of slotted teeth, the origin of dinosaurs and the sister group of crocodiles, among which the origin of slotted teeth and the origin of dinosaurs have been hotly debated recently. The newly discovered fossils in recent years, especially a series of fossils found in western Liaoning, China, have once again stirred up the debate about the origin of birds, proving that birds are really descendants of dinosaurs.
Using an electron microscope, scientists found a melanosome in dinosaur fossils, which is also found in bird feathers, which is a continuation of dinosaur genes best supports the above conclusion.