Chevron (anatomy)
Diplodocus chevron
Caudal vertebrae of Diplodocus carnegii showing the double-beamed chevron bones that the genus name refers to, Natural History Museum, London.
A chevron is one of a series of bones on the ventral (under) side of the tail in many reptiles, dinosaurs (such as Diplodocus; see picture), and some mammals such as kangaroos and manatees.
Their main function is to protect critical elements in the tail such as nerves and blood vessels from being damaged when the animal either supports its weight on its tail, or pushes it against a hard surface to propel itself.