Tusk

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Tusks are elongated, continuously growing front teeth, usually but not always in pairs, that protrude well beyond the mouth of certain mammal species. They are most commonly canine teeth, as with warthogs, pigs, and walruses, or, in the case of elephants, elongated incisors. In most tusked species both the males and the females have tusks although the males' are larger. Tusks are generally curved, though the narwhal's sole tusk is straight and has a helical structure. Continuous growth is enabled by formative tissues in the apical openings of the roots of the teeth.[1][2] In earlier times[when?] elephant tusks weighing over 90 kg (200 lb) were not uncommon, though it is rare today to see any over 45 kg (100 lb).[3]

Function[edit]

Tusks have a variety of uses depending on the animal. Social displays of dominance, particularly among males, are common, as is their use in defense against attackers. Elephants use their tusks as digging and boring tools. Walruses use their tusks to grip on ice and to haul out on ice.[4] The presence of a tusk in only the male narwhals suggests that for these whales the tusk is a secondary sex characteristic.[5]

Use by humans[edit]

Tusks are used by humans to produce ivory, which is used in artifacts and jewellery, and formerly in other items such as piano keys. Consequently, many tusk-bearing species have been hunted commercially and several are endangered. The ivory trade has been severely restricted by the United Nations Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES).

Gallery[edit]

See also[edit]

References[edit]

  1. ^ "Tusk". The Oxford English Dictionary. 2010.
  2. ^ Konjević, Dean; Kierdorf, Uwe; Manojlović, Luka; Severin, Krešimir; Janicki, Zdravko; Slavica, Alen; Reindl, Branimir; Pivac, Igor (4 April 2006). "The spectrum of tusk pathology in wild boar (Sus scrofa L.) from Croatia" (PDF). Veterinarski Arhiv. 76 (suppl.) (S91–S100). Retrieved 9 January 2011.
  3. ^ "Still Life" by Bryan Christy. National Geographic Magazine, August, 2015, pp. 97, 104.
  4. ^ Fay, F.H. (1985). "Odobenus rosmarus". Mammalian Species. 238 (238): 1–7. doi:10.2307/3503810. JSTOR 3503810.
  5. ^ "Monodon monoceros". Fisheries and Aquaculture Department: Species Fact Sheets. Food and Agriculture Organization of the United Nations. Retrieved 20 November 2007.