Stegosaurus Had a Stronger Bite Than Its Herbivorous Brethren

Photo courtesy of Stephan Lautenschlager.


Photo courtesy of Stephan Lautenschlager.

The stegosaurus roamed the earth 150 million years ago, eating ferns and horsetails to sustain its bulk. Despite its herbivorous diet, though, it had a strong bite, according to a multiuniversity team of scientists in the United Kingdom. In fact, this bite enabled it to eat a wider range of plants than other herbivorous dinosaurs with similar skulls.

The researchers compared the skull of “Sophie,” a stegosaurus specimen from the Natural History Museum, with the skulls of a plateosaurus and an erlikosaurus. All 3 skulls feature a large, low snout with feeble, peg-shaped teeth and a scissor-like jaw that only can move up and down. Yet computer modeling shows they had different biting abilities.

Lead author Dr. Stephan Lautenschlager, a postdoctoral researcher at the University of Bristol’s School of Earth Sciences, used data from 3-D scans of the skulls and lower jaws as well as engineering software to give the skulls the material properties that would match as closely as possible to the real thing.

For example, Lautenschlager used data on crocodile teeth to help model the teeth of the dinosaurs. Then, by attaching muscles to these models, he was able to examine the forces that the jaws could produce, in addition to the subsequent stresses on the skulls. As computers and software improve, more modeling will be used in research, he said.

“Using computer modeling techniques, we were able to reconstruct muscle and bite forces very accurately for the different dinosaurs in our study,” Lautenschlager said. “As a result, these methods give us new and detailed insights into dinosaur biology, something that would not have been possible several years ago.”

The researchers speculate that the greater bite strength enabled the stegosaurus to eat a broader range of plants. Possibly, then, it may have helped spread the seeds of cycads, which are woody evergreen plants that were abundant during the time of the dinosaurs and whose seeds are contained in large cones.

“Far from being feeble, as usually thought, the stegosaurus actually had a bite force within the range of living herbivorous mammals such as sheep and cows,” said Paul Barrett, a dinosaur researcher at the Natural History Museum.

“The extra information provided by computer modeling is invaluable. Although we can roughly tell what a dinosaur ate from the shape of its teeth and jaws, the differences highlighted by this study indicate that the biology and ecology of these animals is more complex than previously thought,” said Dr. David Button of the University of Birmingham’s School of Geography, Earth, and Environmental Sciences. “As we study the lives of dinosaurs in greater detail, they continue to surprise us.”

The study, “Decoupled Form and Function in Disparate Herbivorous Dinosaur Clades,” was published by Scientific Reports.

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