99-Million-Year-Old Feathery Dinosaur Tail Discovered Frozen in Amber

Researchers have discovered a 99-million-year-old dinosaur tail, complete with feathers, remarkably preserved in a piece of amber, as described in an article in the journal Current Biology.

This finding, which first emerged in Myanmar, provides much more rich evidence about dinosaurs' soft tissues, which are not present in most fossils.

While feathers have been found in amber before, it's usually difficult to determine the animal they come from. But in this case, the researchers are quite certain.

"The feathers definitely are those of a dinosaur, not a prehistoric bird," said Ryan McKellar, from the Royal Saskatchewan Museum, in a press release.

In particular, the tail is from a theropod, a group of dinosaurs from which birds are believed to have evolved.

"The new material preserves a tail consisting of eight vertebrae from a juvenile; these are surrounded by feathers that are preserved in 3D and with microscopic detail," he said. "We can be sure of the source because the vertebrae are not fused into a rod or pygostyle as in modern birds and their closest relatives. Instead, the tail is long and flexible, with keels of feathers running down each side."

The discovery was made by Lida Xing, from China University of Geosciences and the lead author of the paper, in an amber market in Myitkyina, Myanmar, in 2015.

While it was sold as a mere curiosity, Xing recognized it as something special and suggested the Dexu Institute of Paleontology buy it. The research team determined that the tail is around 99 million years old, and it is from the mid-Cretaceous period.

"It's amazing to see all the details of a dinosaur tail – the bones, flesh, skin, and feathers – and to imagine how this little fellow got his tail caught in the resin, and then presumably died because he could not wrestle free," said University of Bristol professor Mike Benton, another of the study's lead authors. "There's no thought that dinosaurs could shed their tails, as some lizards do today."

The feathers themselves appear "chestnut brown" with a lighter underside. This gives researchers rare glimpse into the color of dinosaurs, whose hue is usually lost in fossilization. It also speaks to the power of amber as preserver of ancient organisms.

"Amber pieces preserve tiny snapshots of ancient ecosystems, but they record microscopic details, three-dimensional arrangements, and labile tissues that are difficult to study in other settings," McKellar said. "This is a new source of information that is worth researching with intensity and protecting as a fossil resource."

Movie fans may remember that in the film Jurassic Park, scientists used dinosaur DNA, preserved in amber, to clone the prehistoric animals and bring them back from extinction. However, in the film, the DNA was extracted from ancient mosquitoes that has fed off dinosaurs, rather than from body parts of the dinosaurs.

In November, the journal Paleontology also published a study detailing the discovery of bird plumage that had been preserved from the Cretaceous period, which was revealed to be iridescent and unlike the feathers of modern birds.

Watch the video below for more images of the dinosaur feathers:

Photo credit: Ryan McKellar/Royal Saskatchewan Museum