Paleontologist Lida Xing has made history after discovering what's thought to be the first known dinosaur tail preserved in a piece of amber. Thought to be from the mid-Cretaceous Period the 1.4-inch segment of tail is around 99 millions years old and consists of 8 vertebrae that are very clearly covered in primitive feathers. Based on its structure scientists have been able to rule out the possibility of the tail belonging to a bird and instead believe that it belongs to a juvenile coelurosaur.
Whilst the evidence to support the idea that feathered dinosaurs has been previously found in fossil impressions and dinosaur-era feathers have been found in amber, this discovery is the first that scientists have been able to associate with a dinosaur.
Through this discovery it's hoped that scientists can further their understanding on the evolution and structure of dinosaur feathers. You can read more about the find on National Geographic.