Unfolded egg discovered in fossilized bird remains
Chinese scientists have discovered the fossilized remains of a bird in whose body an undecomposed egg was preserved. The bones belong to a previously unknown species of sparrow-sized bird that lived about 110 million years ago. This is the first such discovery in history.
The fossil was discovered 11 years ago in ponorthwest China. In 2018, paleontologists led by Alida Bailleul of the Chinese Academy of Sciences took a closer look at the fossil and noticed something intriguing: the bird had a strange band of tissue between its pubic bones. Only microscopic examination revealed that the piece of tissue was an unfolded egg, whichore preserved in the body of the bird.
The fossil belongs to a bird the size of wroblah, ktory lived around 110 millionow years ago in the area of present-day China. The previously unknown species was named Avimaia schweitzerae, in honor of the paleontologist Mary Schweitzer, to which theorej of the name refers to the second part of the name. The new species belongs to an extinct group of birdsoin Enantiornithes, whichore commonly found during the Cretaceous period.
DetailedoA detailed description of the finding appeared on the pages of „Nature Communications”.
Scientists were initially surprised by the discovery. They did not suspect that the strange, squashed mass in the headless fossil might be the remains of an egg. But microscopic analysis of the fragmentoIn the fossil, she indisputably pointed out that it is the shell of the j. Further research revealed anomalies thatore suggest that the egg may have been the cause of the bird’s death. The discovery is detailedolnie noteworthy because fully formed eggs usually stay in the body of an adult bird for about 24 hours.
The research also showed that the outermost layer of the eggshell contains mineral particles similar to structures present in eggs wspoof modern waterfowl, such as ducks. This suggests that the species nested near the reservoiroin water. These spheres probably performed the function of protecting the embryo from microbial infections. Similar structures have never before been found in any fossilized eggs.
The egg shell does not have the correct proportions seen in healthy eggs. Researchers have identified numerous layers of it, ktore are very thin. If the egg is not laid, it is covered with another layer of. This can be seen in wspomodern birdow, ktore are exposed to severe stress. This suggests that the egg stayed too long in the bird’s body and was probably the cause of its death.