T rex’s keyhole eye sockets helped its bite, research suggests - The Guardian

“They really had specialised eye socket shapes, which helped them deal with high bite forces,” said Dr Stephan Lautenschlager, a vertebrate palaeontologist at the University of Birmingham and author of the study.

“There’s a bit of a trade-off between better vision, larger eyes, but higher stresses in the skull because of [a circular eye socket],” he said.

“About two-thirds or three-quarters have the typical circular orbit and then the rest are deviating from that and doing something more extreme or more fancy,” said Lautenschlager.

Lautenschlager used a series of computer models to explore the ramifications of the different eye socket shapes, finding that a circular orbit is associated with greater deformation of the bones around the eye socket during biting, and that key-hole or figure-of-eight shaped orbits helped to distribute stresses across the skull so they were not concentrated at one point.

“Interestingly, you see that in juvenile T rex, they still have the perfectly circular or nearly circular orbits, because they didn’t produce that high bite forces presumably, or had slightly different diet, or different prey repertoire,” Lautenschlager added.