Monodontidae









































Monodontidae
Temporal range: Late Miocene–Recent

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Belugawhale MMC.jpg

Beluga whale

Scientific classification edit
Kingdom:
Animalia
Phylum:
Chordata
Class:
Mammalia
Order:
Artiodactyla
Infraorder:
Cetacea
Superfamily:
Delphinoidea
Family:
Monodontidae
Gray, 1821
Genera

See text



The cetacean family Monodontidae comprises two unusual whale species, the narwhal, in which the male has a long tusk, and the dorsal fin-lacking, pure white beluga whale. They are native to coastal regions and pack ice around the Arctic Ocean. Belugas can be found in the far north of the Atlantic and Pacific Oceans; the distribution of narwhals is restricted to the Arctic and Atlantic Oceans.


Both species are medium-sized whales, between three and five metres in length, with a forehead melon, and a short or absent snout. They do not have a true dorsal fin, but do have a narrow ridge running along the back, which is much more pronounced in the narwhal. They are highly vocal animals, communicating with a wide range of sounds. Like other whales, they also use echolocation to navigate.[1]


Monodontids have a wide-ranging carnivorous diet, feeding on fish, molluscs, and small crustaceans. They have reduced teeth, with the beluga having numerous simple teeth, and the narwhal having only two teeth, one of which forms the tusks in males. Gestation lasts 14–15 months in both species, and almost always results in a single calf. The young are not weaned for a full two years, and do not reach sexual maturity until they are five to eight years of age. Family groups travel as part of herds, or 'pods', which may contain several hundred individuals.[1]



Taxonomy




Skull of a cross between a narwhal and a beluga whale, at the Zoological Museum, Copenhagen


The monodontids, oceanic dolphins (Delphinidae) and porpoises (Phocoenidae) together comprise the Delphinoidea superfamily. Genetic evidence suggests the porpoises are more closely related to the white whales, and these two families constitute a separate clade which diverged from the Delphinoidea within the past 11 million years.[2]


Suborder Odontoceti


  • Superfamily Delphinoidea
    • Family Monodontidae

      • Subfamily Delphinapterinae

        • Genus Delphinapterus

          • Delphinapterus leucas, beluga


        • Genus † Denebola
          • Denebola brachycephala


        • Genus † Bohaskaia[3]
          • Bohaskaia monodontoides




      • Subfamily Monodontinae
        • Genus Monodon

          • Monodon monoceros, narwhal







References





  1. ^ ab Brodie, Paul (1984). Macdonald, D., ed. The Encyclopedia of Mammals. New York: Facts on File. pp. 200–203. ISBN 0-87196-871-1..mw-parser-output cite.citation{font-style:inherit}.mw-parser-output q{quotes:"""""""'""'"}.mw-parser-output code.cs1-code{color:inherit;background:inherit;border:inherit;padding:inherit}.mw-parser-output .cs1-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/thumb/6/65/Lock-green.svg/9px-Lock-green.svg.png")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-lock-limited a,.mw-parser-output .cs1-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/thumb/d/d6/Lock-gray-alt-2.svg/9px-Lock-gray-alt-2.svg.png")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/thumb/a/aa/Lock-red-alt-2.svg/9px-Lock-red-alt-2.svg.png")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registration{color:#555}.mw-parser-output .cs1-subscription span,.mw-parser-output .cs1-registration span{border-bottom:1px dotted;cursor:help}.mw-parser-output .cs1-hidden-error{display:none;font-size:100%}.mw-parser-output .cs1-visible-error{font-size:100%}.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registration,.mw-parser-output .cs1-format{font-size:95%}.mw-parser-output .cs1-kern-left,.mw-parser-output .cs1-kern-wl-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right,.mw-parser-output .cs1-kern-wl-right{padding-right:0.2em}


  2. ^ Waddell, V.G. and Milinkovitch, M.C. and Bérubé, M. and Stanhope, M.J. (2000). "Molecular Phylogenetic Examination of the Delphinoidea Trichotomy: Congruent Evidence from Three Nuclear Loci Indicates That Porpoises (Phocoenidae) Share a More Recent Common Ancestry with White Whales (Monodontidae) Than They Do with True Dolphins (Delphinidae)". Molecular Phylogenetics and Evolution. 15 (2): 314–318. doi:10.1006/mpev.1999.0751. PMID 10837160.CS1 maint: Multiple names: authors list (link)


  3. ^ Jorge Vélez-Juarbe and Nicholas D. Pyenson (2012). "Bohaskaia monodontoides, a new monodontid (Cetacea, Odontoceti, Delphinoidea) from the Pliocene of the western North Atlantic Ocean". Journal of Vertebrate Paleontology. 32 (2): 476–484. doi:10.1080/02724634.2012.641705.




External links




  • Media related to Monodontidae at Wikimedia Commons


  • Data related to Monodontidae at Wikispecies










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