When a small, sparrow-sized dinosaur died about 99 million years ago, part of its tail was immaculately preserved in amber. Researchers who recently discovered the tail from a Hukawng Valley amber mine in Myanmar say it's a notable find not only because it is the first dinosaur tail ever identified, but also because it is covered in feathers. Co-first author Lida Xing of China University of Geosciences found the amber piece in a Myanmar market in 2015, according to NPR.