Finite Element Comparison of Cranial Sinus Function in the Dinosaur Majungasaurus and Head-Clubbing Giraffes

Majungasaurus crenatissimus is a spectacularly preserved carnivorous dinosaur from latest Cretaceous Madagascar. Computed tomographic (CT) scans reveal unusual internal anatomy of the dinosaur’s cranium [1,2; Figure 1]: the nasals form a large hollow chamber traversed with bony struts, and a unicorn-like projection of the frontals is also hollow. The wall thickness and struts within these sinuses recall sinuses of giraffes, which strike each other with a median projection (ossicone) above a frontal sinus and lateral ossicones of the parietals [3]. Giraffe-like cranial sinuses, and large attachments for neck muscles [4], raise the hypothesis that Majungasaurus could engage in giraffe-like head strikes to each other’s necks and flanks.