Neural spine sail

A neural spine sail is a large, flattish protrusion from the back of an animal formed of a sequence of extended vertebral spinous processes and associated tissues.

Such structures are comparatively rare in modern animals, but have been identified in many extinct species of amphibians and amniotes.

[2][3] Elaborate body structures of many modern-day animals usually serve to attract members of the opposite sex during mating.

[1] The structure may also have been more hump-like than sail-like, as noted by Stromer in 1915 ("one might rather think of the existence of a large hump of fat [German: Fettbuckel], to which the [neural spines] gave internal support")[4] and by Jack Bowman Bailey in 1997.

[7] In 2022, a detailed study was published by Cerda et al. analyzing the structure, morphology, and microanatomy of the vertebral spines of Amargasaurus.