The tusk of the narwhal ( Monodon monoceros L.): interpretation of its function (Mammalia: Cetacea)

• Published in: Canadian Journal of Zoology
• Main Author: Best, Robin C.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Canadian Science Publishing 1981
• Subjects: The Tusk; Monodon monoceros; narwhal*; Sea ice
• Online Access: http://dx.doi.org/10.1139/z81-319; http://www.nrcresearchpress.com/doi/pdf/10.1139/z81-319

For over a century, scientists have speculated on the biological function of the tusk of the male narwhal. Proposed functions have included use of the tusk as a weapon, use for opening breathing holes in sea ice, use in feeding, use as an acoustic organ, and function as a secondary sex character. The weight of evidence in this literature review supports a theory that the narwhal tusk serves as a secondary sex character of males, for nonviolent assessment of hierarchical status on the basis of relative tusk size. Relative tusk size is evidently determined in frontal encounters by rival males.