Researchers were perusing an amber market in Myanmar when they stumbled across a truly extraordinary specimen, National Geographic reports. Trapped inside a golden piece of amber—already partially shaped to be sold as jewelry—was a fully feathered section of a dinosaur's tail. According to the Los Angeles Times, the person selling the amber thought it was some kind of plant. While scientists have found evidence of feathered dinosaurs, not to mention feathered prehistoric birds, this piece of amber is the first time feathers have been found perfectly preserved and attached to what is unmistakably a dinosaur. The find was published Thursday in Current Biology.
The tail section is believed to belong to a young, sparrow-sized coelurosaur that lived 99 million years ago. Researchers know the tail belongs to a dinosaur because of its articulated vertebrae; birds have vertebrae that are fused together. And because of the way the features are structured, researchers believe they were useless for flight. It remains unclear exactly what purpose the feathers served, though researchers theorize dinosaurs may have used them for camouflage, regulating their body heat, or signaling to other animals. Now that researchers can see how feathers actually appeared on a dinosaur's body, they hope to learn how they evolved for flight in modern-day birds. They also believe that, given access to Myanmar's amber mines, they may one day find a whole preserved dinosaur.