Scientists Found a Fossilized Tumor on a Transylvanian Dinosaur’s Face

Dumbrava et al., 2016
Dumbrava et al., 2016 / Dumbrava et al., 2016

We have very little control over what happens to our bodies after we die. We may gradually crumble away to nothingness, or end up naturally mummified. We may leave behind baby-sized calcified organs. Or we, with all our lumps and bumps, may become fossils. Such was the case with the remains of a little duck-billed dinosaur, whose facial tumor may be the oldest one ever found, according to report on the tumor analysis in the journal Scientific Reports.

Transylvania’s Hateg Basin has produced a wealth of dinosaur specimens dating to the end of the Cretaceous Period more than 65 million years ago. One such specimen was a fossilized lower jaw recovered in the mid-2000s by the University of Bucharest’s Zoltán Csiki-Sava, an author on the current paper. At the time, Csiki-Sava identified the jawbones as those of a dwarf duck-billed dinosaur called Telmatosaurus transsylvanicus. The bones were small, even for a dwarf, which led the researchers to believe that their owner had died before reaching adulthood.

The specimen had another unusual feature: a bulge on its left side. To figure out what had caused that bulge without taking the specimen apart, Csiki-Sava and his colleagues brought the specimen to a micro-computed tomography (micro-CT) scanning facility in Switzerland.

Image credit: Dumbrava et al., 2016 in Scientific Reports

The scans revealed that the bump was an ameloblastoma, a type of non-cancerous facial tumor known to affect people and other mammals. Only last year did researchers find the first ameloblastoma in a snake.

Co-author Kate Acheson is a Ph.D. student at the University of Southampton in the UK. “This discovery is the first [ameloblastoma] described in the fossil record and the first to be thoroughly documented in a dwarf dinosaur,” she said in a press statement. “Telmatosaurus is known to be close to the root of the duck-billed dinosaur family tree, and the presence of such a deformity early in their evolution provides us with further evidence that the duck-billed dinosaurs were more prone to tumors than other dinosaurs.”

Was the tumor what killed this dinosaur? Probably not, but it wasn’t helping, says Csiki-Sava. “We know from modern examples that predators often attack a member of the herd that looks a little different or is even slightly disabled by a disease. The tumor in this dinosaur had not developed to its full extent at the moment it died, but it could have indirectly contributed to its early demise.” 

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