One hundred and forty-five million years ago, a sauropod wandered who must have felt bad. His nose was bleeding with mucus, and the Jurassic herbivore had a fever and coughing fits that caused his long, muscular neck to shake up and down. The condition may be fatal for him; The disease had such a significant impact on the health of the dinosaurs that it left visible traces in the fossilized bones of the animal.
Paleontologists say these strange remains are the first evidence of infection of the respiratory system of the 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 Carrie Woodruff of the Great Plains Dinosaur Museum in the US state of Montana studied this double focusLike a herbivore and saw something strange. The cavities of the cervical vertebrae contained abnormalities somewhat similar to cauliflower.
“I’ve seen a lot of sauropod vertebrae and come across a lot of strange things, but I’ve never seen such structures before,” Woodruff says.
Take pictures and post them on social media. He soon received responses from scientists who stated that the structures resembled the distortions seen in modern birds and reptiles. Some of these experts contributed to Woodruff’s research. The team concluded that the fossils showed signs of disease in the lungs of dinosaurs, according to a recent research paper in the journal. Scientific Reports.
“Animals have suffered from all kinds of diseases since the dawn of evolution,” said study co-author Ewan Wolf, a paleontologist at the Rocky Mountain Museum in Montana.
Fossils like Dolly allow experts to trace the evolution of contemporary diseases and conditions.
“With these kinds of research organisms, we can learn more about the kinds of diseases that dinosaurs had millions of years ago,” said paleontologist Joseph Peterson of the University of Wisconsin Oshkosh, who was not involved in the study.
It is difficult to diagnose a disease that a dinosaur suffered, especially when the patient died nearly 150 million years ago. There are all kinds of diseases that lead to respiratory diseases, so scientists had to narrow down the options.
Using tools such as X-rays, CT scans, and analysis of thin slices of bone, the microstructure of the fossils can be seen, which provides a lot of information. But the main evidence for the air condition of this dinosaur came from comparing the bones with those of other animals.
Birds are living dinosaurs, Wolf said, and crocodiles are the group most closely related to dinosaurs today. It’s also possible that their common diseases or immune responses were also important to dinosaurs that couldn’t fly, like Dolly. Sauropods like Dolly, like modern birds, had a complex system of air sacs in and around their bones, which were part of their airways.
Based on their research on Dolly and other organisms, Woodruff, Wolf and colleagues suggest it was most likely a pneumonia-like condition known as air sac infection. This can be caused by bacteria, fungi, or viruses. For example, modern chickens can get an air sac infection due to coli bacteria When they live in unsanitary conditions.
“The researchers provided strong evidence of an infection in the air sac,” said paleontologist Cynthia Fu from 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 disease on dinosaur bones is very similar to the effect of disease on vertebrates that still exist today.
“We can apply our knowledge about the effects of disease on bone material from living animals to prehistoric animals and draw logical conclusions,” Fu says.
Based on observations of contemporary birds with an air sac infection, Woodruff and colleagues hypothesize that Dolly suffered greatly from the disease. “Coughing, difficulty breathing, lethargy, fever, sneezing, diarrhea: these are the kinds of symptoms we see in today’s birds with respiratory disease,” Woodruff says.
Illness was also likely the cause of Dolly’s death. While it’s impossible to determine how the dinosaurs died, Woodruff notes that bisexuals like Dolly lived in herds, but diseased animals may have stayed or left the group. Dolly may have died later from the effects of the disease, or it was an easy snack for a hungry predator.
Discovering what kinds of diseases the dinosaurs developed may provide scientists with more knowledge about previously undiscovered aspects of dinosaur behavior, Peterson says.
Wolf notes that one of the ways air sac infections are now spreading among birds is when animals live closely together in conditions where high concentrations of feces and eggs spread bacteria and lead to disease. Sauropods like Dolly have been known to have their young in colonies. In certain cases, an outbreak of air sac infection can occur in these breeding areas.
Dolly’s crumbling bones are also a unique connection to the past. It’s hard to imagine certain fossil injuries, such as bite marks or fractures, Woodruff said. But respiratory illness is something people know all too well.
“We’ve all had symptoms like this, and we probably felt as bad as Dolly as a result,” Woodruff says. “Personally, I don’t know a single fossil I can sympathize with more.”