Discoveries

April 13, 2023

Killer Smile

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A new study has suggested that the famous Tyrannosaurus rex did not openly display its deadly teeth, Smithsonian Magazine reported.

Instead, paleontologists believe the king of the dinosaurs had lizard-like lips that would cover its large dentures.

Scientists have theorized that the T. rex had a mouth more akin to today’s crocodiles, in which the teeth are visible even with a closed jaw.

Still, there is the issue of tooth decay: Crocodilian teeth suffer lots of damage during a lifetime because of exposure to air. An American alligator can go through 3,000 teeth in its life.

The extinct T. rex, however, would have needed around two years to replace just one tooth, according to the researchers.

To figure out this mystery, a research team carefully studied the tooth of a T. rex relative, the Daspletosaurus. They noticed that the enamel in the giant lizard’s tooth lacked significant wear – meaning that it was not exposed to the elements.

The team then compared the skull lengths and tooth sizes of more than 20 theropod dinos and other lizard species. Their findings showed that the T. rex was hiding its killer smile behind a lipped mouth, similar to Komodo dragons.

While other paleontologists are not convinced by the findings, the authors noted that the discovery of a mummified T. rex fossil might help settle the debate.

This story originally appeared in the April 13, 2023 newsletter, Allies, Enemies and Other Horrors.