Brussels scientist discovers red-fanged rodent

A palaeontologist working for the Royal Belgian Institute for Natural Sciences in Brussels has discovered a 70-million-year-old mammal with blood-red teeth that lived on an island in the region of Transylvania in what is now Romania. 

According to researcher Thierry Smith, the fossil of Barbatodon transylvanicus (pictured) is the oldest known example of a mammal with iron in its teeth, and its skull is the most complete mammal fossil from the Upper Cretaceous period.

Transylvania. Blood-red teeth. Could it be? But no: The red in the enamel of Barbatodon’s incisors and on the surface of its molars is not from sucking blood but from the presence of iron in the enamel. Although Barbatodon was discovered by the river Barbat, just 200 kilometres from the castle of Vlad Dracul, the creature apparently didn’t drink blood.

“This rodent-like mammal had long incisors and ate very hard food, like grain,” explains Smith. “Thanks to spectrometric analyses carried out using an electron microscope, we observed that the red enamel was composed of 6.88% iron, which provides teeth with protection from wear and tear. This was particularly important for the animal as it couldn’t grow another set of teeth.” Some present-day rodents have also been observed with iron in their tooth enamel.

It’s significant, Smith says, that the unusual find came on what used to be Hateg Island, a part of southern Europe that was an archipelago 70 million years ago. Barbatodon lived there with a population of dwarf dinosaurs, and the specimen found is at least 15 million years older than the one previously thought to be the oldest.

“Islands are often a refuge for primitive species,” explains Smith, “They survive longer on them than on the mainland, and often natural selection on islands favours smaller species, like the Flores Man or Sicilian pygmy elephants.”

Smith’s work was in conjunction with Vlad Codrea of the university of Babès-Bolya in Romania, and their paper on Barbatodon transylvanicus appears in the latest edition of the journal PLOS One.

Photo courtesy Thierry Smith/RBINS