A comparison of the largest wide plate (A) next to the largest tall plate (B) of the studied Stegosaurus mjosi plates. (Saitta ET (2015) Evidence for Sexual Dimorphism in the Plated Dinosaur Stegosaurus mjosi (Ornithischia, Stegosauria) from the Morrison Formation (Upper Jurassic) of Western USA. PLOS ONE 10(4): e0123503. doi:10.1371/journal.pone.0123503)
The plates of the Stegosaurus — the large, bony discs that lined the dinosaur's neck, back and tail in two staggered rows — may have differed between males and females, a new study finds.