A segment from the feathered tail of a dinosaur that lived 99 million years ago is preserved in amber. A Cretaceous-era ant and plant debris were also trapped in the resin.
The tail of a 99-million-year-old dinosaur, including bones, soft tissue, and even feathers, has been found preserved in amber, according to a report published today in the journal Current Biology.
A Telling Tail
The semi-translucent mid-Cretaceous amber sample, roughly the size and shape of a dried apricot, captures one of the earliest moments of differentiation between the feathers of birds of flight and the feathers of dinosaurs.
Inside the lump of resin is a 1.4-inch appendage covered in delicate feathers, described as chestnut brown with a pale or white underside.
CT scans and microscopic analysis of the sample revealed eight vertebrae from the middle or end of a long, thin tail that may have been originally made up of more than 25 vertebrae.
Feathered, but might It Fly?
The presence of articulated tail vertebrae in the pattern enabled researchers to rule out the probability that the feathers belonged to a prehistoric fowl. Contemporary birds and their closest Cretaceous ancestors function a set of fused tail vertebrae known as a pygostyle that permits tail feathers to maneuver as a single unit.
“[A pygostyle] is the style of factor you’ve got seen if you happen to’ve ever cook a turkey,” says gain knowledge of co-author Ryan McKellar, curator of invertebrate paleontology at Canada’s Royal Saskatchewan Museum.
The current study concludes that if the entire length of the dinosaur tail was covered in the type of feathers seen in the sample, the dinosaur “would likely have been incapable of flight.” Rather, such feathers may have served a signaling function or played a role in temperature regulation, says McKellar.
“MAYBE WE CAN FIND A COMPLETE DINOSAUR.”
The weakly developed tail feathers also suggest that the owner of the Cretaceous tail falls somewhere lower down on the evolutionary tree of theropod dinosaurs, “perhaps a basal [primitive] maniraptoran,” Xida suggests, referring to the subgroup of coelurosaurs that includes oviraptorosaurs and therizinosaurs.
That study revealed the presence of ferrous iron, a decomposition product from the blood hemoglobin that was once present in the dinosaur’s soft tissue.
“The fact that [the iron] is still present gives us a lot of hope for future analysis, to obtain other chemical information on things like pigmentation or even to identify parts of the original keratin,” says McKellar. “Maybe not for this particular specimen, but for other [samples] down the road.”
Meanwhile, Xing believes that the “nearing end” of a decades-old conflict between the Myanmar government and the Kachin Independence Army, which controls the Hukawng Valley, will lead to increased scientific access to the amber mines and, in, turn, to an increase in spectacular discoveries.
“Maybe we can find a complete dinosaur,” he speculates, rather confidently.
source: National Geographic Channel