Two paleontologists have uncovered evidence that a dinosaur fossil, excavated way back in 1942, was hiding a record number of injuries. It had at least eight bone fractures and sites of damage through infection. As the new study in PLOS ONE reveals, this beast lived on despite its dramatic injuries – but it probably would have been in a considerable amount of pain.
The dinosaur in question is a species called Dilophosaurus wetherilli, a feathered creature that roamed the Earth 193 million years ago, during the Early Jurassic. It was made famous by the film "Jurassic Park" as the small, venom-spitting reptile with a retractable frill around its neck, although these two features were fabrications.
In reality, this dinosaur was larger, at about six meters (20 feet) long and up to 500 kilograms (1,100 pounds) in weight. Based on its frightening array of sharp teeth and powerful legs, it was a carnivore. This new study, which reexamined the original D. wetherilli fossil, reveals that it appeared to have experienced a range of injuries rather suddenly – perhaps the result of a single, brutal battle.
A fractured left shoulder blade, a serious bone infection in its left thumb, trauma to its upper right arm, and a break in its lower left arm are just some of its afflictions. It also appeared to have examples of bone deformation, leaving it with at least one permanently twisted finger; this is likely to be the result of a condition called osteodysplasia, where unusual skeletal growth causes imperfectly aligned or positioned joints or bones.
According to Phil Senter, a professor of biology at Fayetteville State University in North Carolina and co-author of the study, as this finger was always protruding from the hand, the dinosaur was constantly flipping the bird. “It wasn’t being rude,” Senter said in a statement. “It just couldn’t help it.”
The dinosaur’s right hand had a permanently extended finger. Phil Senter & Sara Juengest/PLOS ONE
A long section of bone in one of its forearms is also completely missing. Unlike mammals, dinosaurs were unable to re-grow lost bone, meaning that this particular Jurassic beast had to live without this chunk of bone for the rest of its life. The fractures, however, show signs of healing and growth, meaning that this dinosaur lived on for many more months or even several years after acquiring the injuries.
Its hands, presumably used in combat, were rendered partly inoperable, meaning that it would have been unable to pounce on large dinosaurs in order to kill and consume them. Consequently, it would likely have had to live off smaller, passive prey to get by, which may have caused it to experience a dramatic loss in weight.
The cause of these eight injuries is impossible to determine for sure, but the authors suggest that a battle with a fellow dinosaur may have been to blame. Being thrown quite aggressively against a rock or tree while fending off a predator, or even some particularly defensive prey, may have done the trick.
All in all, this D. wetherilli has the most upper-body injuries ever seen for a theropod dinosaur, a group of bipedal, mostly carnivorous dinosaurs. The previous record-holder was a Tyrannosaurus rex named Sue, which had four bone injuries.