One hundred and forty-five million years ago, there was a sauropod walking around that must have felt bad. Mucus was dripping from his nostrils, and the Jurassic herbivore had fevers and fits of coughing that made his long, muscular neck shake. The condition may prove fatal to him; The disease had such a profound effect on the health of the dinosaur that it left visible traces in the animal’s fossilized bones.
According to paleontologists, these strange remains are the first evidence of airway inflammation in a dinosaur.
Scientists who examined the remains of the animal nicknamed “Dolly” didn’t immediately see what was wrong with the poor sauropod. In 2018, paleontologist Kari Woodruff of the Great Plains Dinosaur Museum in Montana, USA, studied these DiplodocusLike a herbivore and saw something strange. In the recesses of the cervical vertebrae there were growths somewhat resembling cauliflower.
“I’ve seen a lot of sauropod vertebrae and found a lot of strange things, but I’ve never seen this kind of structure,” says Woodruff.
Take pictures of it and post it on social media. He soon received responses from scientists who stated that the structures resembled abnormalities also seen in modern birds and reptiles. Some of these experts contributed to Woodruff’s research. The team concluded that the fossils show evidence of a condition in the dinosaurs’ lungs, according to a recent article published in the journal. Scientific reports.
“Animals have suffered from all kinds of diseases since the beginning of evolution,” said co-author Ewan Wolfe, who works as a paleontologist at the Museum of the Rocky Mountains in Montana.
So thanks to paleontologists like Dolly, experts can trace the evolution of contemporary diseases and disorders.
“These kinds of things allow us to learn more about the types of diseases that dinosaurs suffered from millions of years ago,” said paleontologist Joseph Peterson of the University of Wisconsin-Oshkosh, who was not involved in the study.
It is not easy to diagnose a disease that a dinosaur suffered from, especially when the patient must have been dead for nearly 150 million years. There are all kinds of diseases that lead to respiratory illnesses, so scientists had to narrow down the possibilities.
Tools such as X-rays, computed tomography, and analysis of thin slices of bone allow the microstructure of fossils to be seen, providing a great deal of information. But the main evidence of this dinosaur’s air condition came from comparing its bones to those of other animals.
Birds are living dinosaurs, Wolf said, and crocodiles are the current group most closely related to dinosaurs. The diseases or immune reactions that occur in them may also have been important for dinosaurs that could not fly, such as Dolly. Sauropods like Dolly, like modern birds, had a complex system of air sacs in and around their bones that form part of their airways.
Based on their research on Dolly and other creatures, Woodruff, Wolfe, and colleagues suggest that a pneumonia-like condition, also known as air sac infection, is likely involved. This can be caused by bacteria, fungi, or viruses. For example, modern chickens can get air sac infection from coli when they live in unsanitary conditions.
“The researchers provide strong evidence of airborne infection,” said paleontologist Cynthia Fu of Washington State University, who was not involved in the study. It is difficult to make a definitive diagnosis, even in living animals, but the effect of the disease on dinosaur bones is very similar to the effect of the disease on vertebrates living today.
“We can apply our knowledge about the effects of disease on bone matter from living animals to prehistoric animals and draw logical conclusions,” Fu says.
Based on observations of contemporary birds with airborne infections, Woodruff and his colleagues believe that Dolly suffered greatly from the disease. “Coughing, difficulty breathing, lethargy, fever, sneezing, and diarrhea are the symptoms we see in today’s birds with respiratory disease,” Woodruff says.
It is likely that disease was the cause of Dolly’s death. While it’s impossible to say exactly how dinosaurs came to an end, Woodruff notes that tyrannosaurs like Dolly lived in herds, but that diseased animals may have stayed or left the group. Perhaps Dolly then died from the effects of the disease, or she was an easy snack for a hungry predator.
Discovering the types of diseases that affected dinosaurs could give scientists more insight into previously undiscovered aspects of dinosaur behavior, Peterson says.
One way air sac infections now spread among birds, Wolf notes, is when the animals live in crowded conditions where the high concentration of feces and eggs spreads bacteria and leads to disease. Sauropods like Dolly have been known to have had their young in colonies. In certain cases, outbreaks of airsac infection can occur in these breeding areas.
Dolly’s injured bones are also a unique connection to the past. Some fossil injuries, like healed wounds or broken bones, are hard to imagine, Woodruff says. But respiratory illness is something people know very well.
“We’ve all had symptoms like this, and we probably felt as bad as Dolly,” says Woodruff. “Personally, I don’t know of any fossil that I can empathize with better.”