The Softer Side of Dinosaur Fossils

Wednesday, November 14, 2018

Usually, when a plant or animal becomes a part of the fossil record, it is a hard part of the organism that preserves. Dinosaur bones, petrified wood, fossil shells – these are all common fossils that represent the hardest parts of those animals and plants. Very little else is usually preserved.

However, in exceptional circumstances, exceptional fossilization can occur. One of the places that palaeontologists have been finding many exceptionally preserved fossils recently has been from the Jiufotang Formation of Liaoning Province, China.

Recently, researchers from China, including friend of the Philip J. Currie Dinosaur Museum Dr. Jingmai O’Connor, have described a fossil bird from 120 million years ago with fossilized lung tissue preserved in the specimen. The find was published in the scientific journal Proceedings of the National Academy of Sciences of the United States of America.

The bird is called Archaeorhynchus (meaning “ancient beak”), and it is one of the oldest fossil birds known with a toothless beak. Not only does this specimen preserve the remains of lung tissue, which look remarkably similar to modern bird lungs, but it also contains roughly 100 small stones that would have occupied a muscular gizzard. The soft tissue evidence in this specimen has brought to light many similarities to features in modern birds that would be unknown without the incredible preservation of the fossil. The lungs themselves were preserved as a whitish mineral of uncertain origin, but the preservation was so good that the microscopic tissue structure was preserved.

There are a lot of uncertainties around exactly how these soft tissues were preserved. But we are learning more and more about dinosaurs from exceptionally preserved fossils, in addition to what we have been able to determine solely from fossil bones. Every new fossil find reveals an exciting new mystery.