Pteranodon was notable for its skull crest. The crest has many blood vessels in it, found especially in male skeletons. It is belived that these were used as mating displays, in a similar fashion to how a male peacock uses its tail feathers. Finds indicate that pteranodon may have gathered in large rookeries during mating season. It is likely that males with bigger and brighter crests would be more appealing to the females.