A study published in Nature Communications by a team of paleontologists with the China University of Geosciences has revealed the discovery of a pair of intact 100-million year-old bird wings fully encased in amber. The tiny wings, which weigh only 1.6 and 8.51 grams respectively, show plumage patterning and colors similar to modern birds.
The wings belonged to specimens of a group of late Cretaceous-era birds called Enantiornithes, first discovered in the 1980s. The birds had teeth and claws on the end of their wings, but otherwise were very similar to the birds of today.
While it has long been suspected that many, if not all, dinosaurs were covered in feathers, the find shows that birds very similar to today’s avians were present by the Cenomanian period, which marked the beginning of Earth’s late Cretaceous period:
At this point, the primary insight gained from the mummified amber wings is that most of the feather types found in modern avialans were likely also present in Enantiornithes, with comparable feather arrangement, pigmentation and microstructure.
The perfectly preserved wings are believed to have belonged to juvenile birds, based on the development of the bones within them. The wings are so intact that scientists are able to study claws, muscles, and skin, as well as microscopic structures such as follicle arrangement and feather microstructures, a first for the ancient species of birds to whom the wings belong.
According to Ryan McKellar, curator of invertebrate palaeontology at Canada’s Royal Saskatchewan Museum, it is unusual for prehistoric bird wings to be so perfectly preserved:
The biggest problem we face with feathers in amber is that we usually get small fragments or isolated feathers, and we’re never quite sure who produced [them] […] We don’t get something like this. It’s mind-blowingly cool.
The tiny black wings were discovered in a cache of amber fossils in the Kachin state of Myanmar/Burma. Burmese amber is highly prized among paleontologists due to the abundance of fossilized biological specimens it has produced.
Burmese amber, however, is also highly prized by jewelry makers, making the discovery and preservation of fossils difficult. The piece of amber in which these wings were found were originally slated to be made into jewelry, one piece of which was to contain the smaller of the two wings.