Buzz
Dinosaurs have always intrigued us. Occasionally, a fossil is unearthed that sheds new light on their lives—offering insights into their diets, injuries, or living conditions. Interestingly, some fossils also show signs of diseases that once plagued these mighty creatures. Indeed, dinosaurs weren't exempt from illnesses, just like any other living beings.
These diseases severely impacted the dinosaur population, with many falling victim to them. Some of these ailments still exist today, and even affect humans, which adds another layer of intrigue to the story. We've also included some early reptiles that coexisted with dinosaurs during that era.
10. Dandruff
A 125-million-year-old dinosaur holds the record as the oldest known creature to have suffered from dandruff. This dinosaur is the microraptor, a small carnivorous species comparable in size to a modern crow. Additionally, evidence of dandruff has been found in two other dinosaurs: the beipiaosaurus and the sinornithosaurus, both of which were roughly twice the size of the microraptor.
The discovery of dandruff came about serendipitously as scientists were investigating how dinosaurs shed their feathers. During their research, they noticed that certain sections of the fossilized feathers contained corneocytes. This was significant because corneocytes are the same cells involved in human dandruff.
Although the researchers didn't immediately refer to the findings as dandruff, as corneocytes were thought to only form on skin and not on feathers, their discovery provided new insights. The team also observed that dinosaurs shed their feathers in small fragments, much like modern birds, rather than in large clumps as one might expect from creatures of their size.
9. Cancer
Dinosaurs also battled cancer, as revealed by a study conducted by Bruce Rothschild from the Northeastern Ohio Universities College of Medicine in Rootstown, Ohio. Rothschild and his team made this groundbreaking discovery after scanning 10,000 dinosaur fossils stored in various North American museums using an X-ray machine.
The study showed that 29 out of the 97 hadrosaur bones tested contained cancerous tumors. It’s important to note that not all tumors are cancerous, but these were considered to be due to their similarity to tumors found in human cancer patients.
The cause of the hadrosaur's cancer remains unclear, but researchers speculate that it may have been linked to the conifers in their diet. Conifers, with their needlelike leaves, are known to contain substances that can cause cancer.
8. Malaria
Malaria has been claiming lives of organisms since the age of the dinosaurs. Some researchers, such as George Poinar Jr., an entomologist from Oregon State University, even propose that it might have contributed to the extinction of dinosaurs.
Interestingly, this early form of malaria was spread by flying insects, likely not mosquitoes. Research shows that a now-extinct midge, a small flying insect found near rivers, was responsible for transmitting malaria over 140 million years ago. However, scientists also suggest that sand flies and horseflies may have been involved in spreading the disease as well.
These flying insects would have fed on the dinosaurs, much like how the female Anopheles mosquito relies on humans for blood today. The flies infected their dinosaur hosts with an ancient strain of malaria called Paleohaemoproteus burmacis.
While malaria certainly affected the dinosaurs, Poinar does not believe it was the cause of their extinction.
7. Cataracts
While there is no concrete proof that dinosaurs suffered from cataracts, the idea was proposed by L.R. Croft in his book, The Last Dinosaurs. Croft even suggests that the widespread occurrence of cataracts might have contributed to the extinction of dinosaurs.
Croft theorized that dinosaurs began to develop cataracts due to excessive heat and harmful ultraviolet radiation from the Sun, which led to global warming. This radiation caused many dinosaurs to go blind from cataracts, and their inability to survive after losing their sight played a role in their extinction.
Croft also argued that mammals and reptiles managed to survive because they adapted by avoiding the Sun and becoming nocturnal hunters, while dinosaurs continued their daytime activity.
However, many reject the idea that cataracts were responsible for the extinction of dinosaurs. Natural selection would likely have led dinosaurs to develop some kind of defense against the radiation. Moreover, the theory itself is seen by some as implausible.
But then again, this is the explanation you get when you ask an ophthalmologist like L.R. Croft about why dinosaurs went extinct.
6. Osteoarthritis
Osteoarthritis is the most prevalent form of arthritis in humans today. It occurs when the smooth cartilage at the ends of bones deteriorates, causing the rough bone surfaces to rub directly against one another. This leads to friction, gradually wearing down the bones and resulting in pain.
Researchers have found that the Caudipteryx, a small flying dinosaur about the size of a modern peacock, also suffered from osteoarthritis. Remarkably, this dinosaur, which roamed 130 million years ago, is the oldest known creature to have experienced this condition.
The discovery was made while examining the ankle bones of various birds and flying dinosaurs housed in Chinese museums. Out of 10 fossils of the Caudipteryx, 3 showed signs of the condition. The cause of the dinosaur’s vulnerability remains unclear, although many small modern birds also suffer from osteoarthritis.
5. Osteomyelitis
In 1997, researchers uncovered the remains of a Lufengosaurus huenei, a dinosaur that lived between 170 and 200 million years ago. Upon examination, they noticed that its ribs were oddly damaged, with several sections missing, suggesting it had sustained injuries prior to its death. However, the researchers didn’t investigate the cause of the injuries and left the fossil in storage.
Two decades later, researchers revisited the fossil and concluded that the rib damage had been caused by an attack from a larger predator. The identity of the predator remains a mystery, but given the size of the Lufengosaurus huenei, which grew to 6 meters (20 ft) and weighed nearly two tons, the attacker must have been enormous.
The Lufengosaurus huenei managed to escape, but it suffered a serious rib injury that became infected with harmful bacteria. The infection led to the formation of pus within the rib bones, causing a deadly bone disease known as osteomyelitis.
In humans, osteomyelitis is typically caused by Staphylococcus aureus. However, researchers did not determine whether this same bacteria was responsible for the bone disease in dinosaurs. Still, the disease likely caused high fever, fatigue, and nausea, potentially leading to the dinosaur's death. In some cases, the bacteria might have spread to the brain, accelerating the animal's demise.
Interestingly, the dinosaur may have still developed this condition even without being bitten. The bacteria could have entered the body in another manner and then spread to the rib bones via the bloodstream.
4. Septic Arthritis
The hadrosaur, a plant-eating duck-billed dinosaur, appeared to be one of the unluckiest creatures, suffering from a range of ailments. In addition to cancer, it also battled septic arthritis, a painful joint condition that would have caused significant discomfort.
Unlike osteoarthritis, septic arthritis occurs when germs enter the bloodstream and travel to the joints. It can also be introduced directly into the joints through injury. In either case, it results in severe joint pain, sometimes making movement difficult or even impossible.
While examining the elbow fossil of a hadrosaur, researchers discovered signs of septic arthritis. They found three abnormal growths around the joints, all caused by the disease. Although the exact cause of the infection remains unclear, scientists believe it was so painful that the dinosaur may have had trouble walking.
3. Tuberculosis And Pneumonia
Pneumonia and tuberculosis existed long before dinosaurs. The earliest traces of these lung diseases were found in the Proneusticosasiacus, a marine reptile that lived over 245 million years ago.
The discovery was made when researchers analyzed a Proneusticosasiacus fossil using X-ray technology. They observed that some of its ribs appeared abnormal. Initially, they considered possibilities like injury, cancer, fungi, and scurvy, but eventually concluded the cause was pneumonia and Pott’s disease, a severe form of tuberculosis that typically affects the bones.
The researchers found that the reptile likely suffered from this infection for months or possibly years before its death. However, other scientists believe the fossil could belong to a Cymatosaurus, a marine reptile closely related to the Proneusticosasiacus.
The Proneusticosasiacus and Cymatosaurus share a close relation to the nothosaur, a reptile that lived and reproduced on land but hunted in water, much like today's seals. Interestingly, seals are the most likely marine mammals to contract tuberculosis.
2. Tooth Decay
The Labidosaurus hamatus (also known as the lipped lizard) is an extinct creature that many of us have probably never encountered. This 1-meter-long (3 ft) reptile lived during the same time that dinosaurs roamed the Earth, but it is famous for another reason: it is the earliest known creature to have experienced toothache and decay.
This discovery was made a few years ago when Robert Reisz from the University of Toronto Mississauga led a research team to scan the lower jaw of a Labidosaurus hamatus fossil. The analysis revealed that this creature had suffered severe tooth decay, leading to the loss of several of its teeth.
Although the exact cause of the infection remains unclear, researchers believe it could be related to the creature’s diet. The Labidosaurus hamatus was an omnivore, but its primary food source consisted of plants. Herbivores and omnivores with a primarily plant-based diet often have teeth specialized for chewing.
This posed a significant problem for the Labidosaurus hamatus. The constant chewing wore down its enamel, exposing the nerves inside its teeth. Bacteria then infected these nerves, leading to an abscess and a painful toothache, which eventually resulted in tooth decay.
1. Intestinal Worms
Dinosaurs were afflicted by various parasitic worms, including tapeworms and trematodes. While researchers are unsure how large these tapeworms grew, it’s believed they could have reached lengths of up to 30 meters (100 ft), which might seem small compared to the immense size of some dinosaurs. For comparison, tapeworms in humans can stretch to more than 24 meters (80 ft).
Finding direct evidence of parasitic worms in dinosaur bones or skin fossils is incredibly rare, as these worms would have likely died and decomposed after the dinosaurs’ extinction. However, scientists can infer the types of worms that affected dinosaurs by studying coprolites (fossilized dinosaur feces), which sometimes contain worm eggs or cysts.
In 2006, researchers George Poinar and Arthur Boucot discovered the first evidence of parasitic worms in dinosaur coprolites. The fossilized poop came from an unidentified carnivorous dinosaur that lived in what is now modern-day Belgium. The researchers identified traces of trematode and nematode worms, along with a protozoan that they suspect to be Entamoeba.
