Over the last few years, a massive deposit of amber in Myanmar has provided a treasure trove of ancient animal remains trapped in fossilized resin. And now researchers have discovered the most complete bird fossil yet found in these amber deposits, as reported exclusively by National Geographic.
The bird was a juvenile that lived 99 million years ago, in the late Cretaceous era. The small animal is encased in cloudy amber and while it might not appear as spectacular as other findings from the last few years, it is what’s inside (the amber) that counts.
As reported in Science Bulletin, the bird is 6 centimeters (2.8 inches) long, making it slightly bigger than the specimen recovered last year, which was 4.5 centimeters (1.8 inches) long. The bird's interior is unusually visible, allowing the researchers to peek inside its body. The specimen features the back of its skull, parts of one wing, bits of one leg, most of the spine, and the hips.
“All of this is now trapped in a wafer of amber about as large as a belt buckle,” co-author Ryan McKellar, from the Royal Saskatchewan Museum in Regina, Canada, told National Geographic. “Even though they are hatchlings, they already have a full set of flight feathers. They have a weakly developed rachis, or central shaft, so they may not have been excellent flyers.”
Based on what the team can extrapolate from the find, the poor creature fell into the resin, although it is unclear if it was dead or alive. When the hatchling died, some of the soft tissue and bones decomposed, and other sediments took their place. Eventually, another layer of resin covered the original deposit. Bits of wood were found in the amber, a strong indication that it settled near or on the forest floor. It also must have been humid when the bird fell, as the specimen's cloudiness is a result of moisture that caused the amber to foam.
“This Myanmar fossil deposit is clearly game-changing. It’s arguably the more important breakthrough for understanding bird evolution right now,” Julia Clarke, an expert on the evolution of birds and flight at the University of Texas at Austin who wasn’t involved in the study, told National Geographic. “We used to think we’d never have a whole bird in Cretaceous amber, but now we have multiple examples.”
Jurassic Park might have crystallized the idea of finding small insects in amber in the public mind, but the reality has been even more exciting, with dinosaur feathers, lizards, and flowers discovered in the fossilized sap.
[H/T: National Geographic]