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The narwhal was scientifically described by Carl Linnaeus in his 1758 publication Systema Naturae. [5] The word "narwhal" comes from the Old Norse nárhval, meaning 'corpse-whale', which possibly refers to the animal's grey, mottled skin and its habit of remaining motionless when at the water's surface, a behaviour known as "logging" that usually happens in the summer.
However, in narwhals the tusk is implanted in the left maxilla, whereas the tusk in Odobenocetops originates in the right premaxilla. The tusks in these two genera are therefore not homologous, and the occurrence of tusks in Odobenocetops is a convergence with narwhals. [4] In the holotype of Odobenocetops peruvianus both tusks are incomplete ...
Tusks are generally curved and have a smooth, continuous surface. The male narwhal's straight single helical tusk, which usually grows out from the left of the mouth, is an exception to the typical features of tusks described above. Continuous growth of tusks is enabled by formative tissues in the apical openings of the roots of the teeth. [2] [3]
The cetacean family Monodontidae comprises two living whale species, the narwhal and the beluga whale and at least four extinct species, known from the fossil record. Beluga and Narwhal are native to coastal regions and pack ice around the Arctic Ocean.
Female beaked whales' teeth are hidden in the gums and are not visible, and most male beaked whales have only two short tusks. Narwhals have vestigial teeth other than their tusk, which is present on males and 15% of females and has millions of nerves to sense water temperature, pressure and salinity.
A former Royal Canadian Mounted policeman accused of smuggling $2 million worth of narwhal tusks into the United States is now in custody.
Tusks are continuously growing incisors. Typically, adult elephant teeth comprise 12 premolars, 12 molars, and two tusks. These twin teeth are composed of four layers, the outermost being the enamel.
"this behaviour may exhibit tusk use as a sensory and communication organ for sharing information about water chemistry sensed in tusk microchannels" this sentence in "Behavior and ecology" largely duplicates "The rubbing of tusks together by male narwhals is thought to be a method of communicating information about characteristics of the water ...