An ancient, hummingbird-size bird got its wing stuck in sticky tree resin and likely struggled for its life about 99 million years ago. Researchers nicknamed this specimen “Angel Wing.”Credit: Chung-tat Cheung
The preserved wings feature bones, soft tissue, and feathers. They most likely belonged to Enantiornithes, a group of avians that died out at the end of the Cretaceous period.
A team of researchers from China, Canada and the U.S. has found an example of mummified remains of a bird from the mid-cretaceous period, in amber. The study of the mummified wings, published in the June 28 issue of Nature Communications and funded in part by the National Geographic Society’s Expeditions Council, indicated they most likely belonged to enantiornithes , a group of avian dinosaurs that became extinct at the end of the Cretaceous period. (Read more about the evolution from dinosaurs to modern birds.)
The team found two bird samples inside a single small piece of amber (which was originally found in Myanmar), both of which belong to enantiornithines—a group of birds that went extinct at approximately the same time as the other dinosaurs—66 million years ago. Prior research had found that such birds had both teeth and wings with claws on their tips. The birds were tiny (the amber piece as a whole was just a few cubic centimeters) and likely juveniles.
In their paper revealing their findings, the researchers “tentatively” suggest that the two wings come from the same species of enantiornithes. And they’re so well-preserved that they show how similar the feathering is to that of modern birds. An x-ray micro-CT analysis revealed that both samples appeared to belong to juveniles, based on bone size and stage of development. Similarities in bone structure and proportion, as well as some plumage characteristics, suggest that they may belong to the same species.
These findings are critical because it’s incredibly rare to find fossils this old and well-preserved. In normal fossilisation processes, feathers tend to disappear, leaving behind only difficult-to-interpret impressions on surrounding rock. And when feathers do turn up in amber, it’s usually alone and without much context. These wings though are astonishingly complete.
- Lida Xing et al. Mummified precocial bird wings in mid-Cretaceous Burmese amber, Nature Communications (2016). DOI: 10.1038/ncomms12089