Dinosaurs Once Had Furs and Feather Covering Their Body, Study Finds Evidence of Bird-Like Features

We have learned about dinosaurs being ferociously built with scales on their skin. Little did we know that some dinosaurs used to be covered in furs and feathers. There used to be a relative of the Tyrannosaurus Rex who had a shaggy coat of filaments to cover their skin. These dinosaurs lived about 150 million years ago and were called Yutyrannus huali and they weighed almost 1.5 tons, according to the American Museum of Natural History.

The Yutyrannus' coarse coat was made out of filaments known as proto-feathers, like those found in birds. A range of different species of dinosaurs were discovered along with the Yutyrannus who had feathered bodies. Most of these dinosaurs belonged to the family tree of theropods. Experts also stumbled upon evidence of feathered ornithischians distantly related to birds. Paleontologists uncovered more of these feathered fossils of Sinornithosaurus from the Liaoning Province of China, helping them understand the evolution of birds from dinosaurs. 

The fossils discovered in China were well-preserved and even showed the feathered features of the dinosaurs. Some scientists theorized that all the dinosaurs, including sauropods, had feathers similar to all the mammals having some hair on their bodies. A study published in Nature revealed how researchers from the University College Cork, the Stanford Synchrotron Radiation Light Source at the Department of Energy's SLAC National Accelerator Laboratory and other instituted joined hands to study the traces of protein that were found in the fossils of the feathered dinosaurs. 

"It’s really exciting to discover new similarities between dinosaurs and birds," Tiffany Slater, a paleontologist at UCC and lead author on the new study, said according to the Lab Manager. "Using X-rays and infrared light, we found that feathers from the dinosaur Sinornithosaurus contained lots of beta-proteins, just like feathers of birds today. This finding validates our hypothesis that dinosaur birds had stiff feathers—like in modern birds."

Slater and fellow UCC paleontologist, Maria McNamara, teamed with SSRL scientists to analyze 125-million-year-old feathers from the dinosaur Sinornithosaurus and the early bird Confuciusornis. Their analysis shed some light on the fossil feathers having high concentrations of alpha proteins which developed over time. "So although some dinosaur feathers do preserve traces of the original beta-proteins, other fossil feathers contain alpha-proteins that formed during fossilization," Slater explained. "Traces of ancient biomolecules can clearly survive for millions of years, but you can’t read the fossil record literally because even seemingly well-preserved fossil tissues have been cooked and squashed during fossilization," McNamara added.

The real question is, what was the importance of those dinosaurs having feathers on their bodies? Bird-like raptors and horned dinosaurs also had a coat of filaments covering their bodies at one point, according to the Smithsonian Museum. The fur cover on their bodies helped the dinosaurs to stay warm and camouflage themselves. In 1996, experts discovered the Sinosauropteryx, a 124-million-year-old species of dinosaur that belonged to a group of small carnivores called compsognathids. They also had a fuzzy coat covering their bodies.

Another small and horned dinosaur called Psittacosaurus used to have bristle-like structures protruding along its tail. Those bristles were similar in structure to other protofeathers and only covered a portion of the dinosaur’s tail. The paleontologists also described a small flightless dinosaur in 1917 resembling ostriches with a long tail and clawed hands. The Struthiomimus and the feathers on its bodies were not initially detected after experts studied the fossils of that dinosaur. One of the most well-recognized feathered dinosaurs was the Caihong. The 161 million-year-old fossils of the Caihong revealed how they used to have colorful feathers and grew up to the size of a cow and could fly.