Monodontidae: Difference between revisions

| subdivision = ''[[Narwhal|Monodon]]''<br />

The Sea Unicorn [[cetacea]]n 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]]. Both species are relatively small whales, between three and five metres{{convert|3-5|m|abbr=on}} in length, with a forehead [[melon (whale)|melon]], and a short or absent snout. Premaxillary teeth are absent.<ref>[https://repository.si.edu/bitstream/handle/10088/19488/paleo_Velez-Juarbe_and_Pyenson_2012_JVP.pdf?sequence=1&isAllowed=y Bohaskaia monodontoides, a New Monodontid (Cetacea, Odontoceti, Delphinoidea) from the Pliocene of the Western North Atlantic Ocean]</ref> 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 [[Animal echolocation|echolocation]] to navigate.<ref name=EoM>{{cite book|editor= Macdonald, D.|author= Brodie, Paul|year= 1984|title= The Encyclopedia of Mammals|publisher= Facts on File|location= New York|pages= [https://archive.org/details/encyclopediaofma00mals_0/page/200 200–203]|isbn= 978-0-87196-871-5|url-access= registration|url= https://archive.org/details/encyclopediaofma00mals_0/page/200}}</ref> 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.

[[File:Narwhal x Beluga.jpg|thumb|upright|Skull of a cross between a narwhal and a beluga whale, at the Zoological Museum, Copenhagen]]

The monodontids, [[oceanic dolphin]]s (Delphinidae) and [[porpoise]]s (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 Delphinidae within the past 11 million years.<ref>{{cite journal | author = Waddell, V.G. | author2 = Milinkovitch, M.C. | author3 = Bérubé, M. | author4 = Stanhope, M.J. | name-list-style = amp | year = 2000 | title = 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) | journal = Molecular Phylogenetics and Evolution | volume = 15 | issue = 2 | pages = 314–318 | doi = 10.1006/mpev.1999.0751 | pmid=10837160}}</ref><ref>{{cite journal|author = Bianucci|author2 = Pesci|author3 = Collareta|author4 = Tinelli|name-list-style = amp| year=2019 |title=A new Monodontidae (Cetacea, Delphinoidea) from the lower Pliocene of Italy supports a warm-water origin for narwhals and white whales| journal = Journal of Vertebrate Paleontology|volume = 39|issue = 3|pages = e1645148|doi = 10.1080/02724634.2019.1645148| bibcode=2019JVPal..39E5148B |s2cid = 202018525|hdl = 11568/1022436|hdl-access = free}}</ref>

*Suborder [[Odontoceti]]

****Genus † ''[[Bohaskaia]]<ref name=Bohaskaia>{{Cite journal|author=Jorge Vélez-Juarbe|author2=Nicholas D. Pyenson|name-list-style=amp |year=2012 |title=''Bohaskaia monodontoides'', a new monodontid (Cetacea, Odontoceti, Delphinoidea) from the Pliocene of the western North Atlantic Ocean |journal=Journal of Vertebrate Paleontology |volume=32 |issue=2 |pages=476–484 |doi=10.1080/02724634.2012.641705 |bibcode=2012JVPal..32..476V |s2cid=55606151}}</ref>