Cetacea (/sɪˈteɪʃə/; from Latin cetus 'whale', from Ancient Greek κῆτος (kêtos) 'huge fish, sea monster')[3] is an infraorder of aquatic mammals belonging to the order Artiodactyla that includes whales, dolphins, and porpoises. Key characteristics are their fully aquatic lifestyle, streamlined body shape, often large size and exclusively carnivorous diet. They propel themselves through the water with powerful up-and-down movement of their tail which ends in a paddle-like fluke, using their flipper-shaped forelimbs to maneuver.[4]
While the majority of cetaceans live in marine environments, a small number reside solely in brackish water or fresh water. Having a cosmopolitan distribution, they can be found in some rivers and all of Earth's oceans, and many species inhabit vast ranges where they migrate with the changing of the seasons.
Cetaceans are famous for their high intelligence, complex social behaviour, and the enormous size of some of the group's members. For example, the blue whale reaches a maximum confirmed length of 29.9 meters (98 feet) and a weight of 173 tonnes (190 short tons), making it the largest animal known ever to have existed.[5][6][7]
There are approximately 89[8] living species split into two parvorders: Odontoceti or toothed whales (containing porpoises, dolphins, other predatory whales like the beluga and the sperm whale, and the poorly understood beaked whales) and the filter feeding Mysticeti or baleen whales (which includes species like the blue whale, the humpback whale and the bowhead whale). Despite their highly modified bodies and carnivorous lifestyle, genetic and fossil evidence places cetaceans as nested within even-toed ungulates, most closely related to hippopotamus within the clade Whippomorpha.
Cetaceans have been extensively hunted for their meat, blubber and oil by commercial operations. Although the International Whaling Commission has agreed on putting a halt to commercial whaling, whale hunting is still going on, either under IWC quotas to assist the subsistence of Arctic native people or in the name of scientific research, although a large spectrum of non-lethal methods are now available to study marine mammals in the wild.[9] Cetaceans also face severe environmental hazards from underwater noise pollution, entanglement in abandoned ropes and nets, collisions with ships, plastic and heavy metals build-up, to accelerating climate change,[10][11] but how much they are affected varies widely from species to species, from minimally in the case of the southern bottlenose whale to the baiji (or Chinese river dolphin) which is considered to be functionally extinct due to human activity.[12]
^Uhen, M.D. (2008). "New protocetid whales from Alabama and Mississippi, and a new Cetacean clade, Pelagiceti". Journal of Vertebrate Paleontology. 28 (3): 589–593. doi:10.1671/0272-4634(2008)28[589:NPWFAA]2.0.CO;2. JSTOR 20490986. S2CID 86326007.
^Fordyce, E.; de Muizon, C. (2001). "Evolutionary history of the cetaceans: a review". In Mazin, J.-M.; de Buffrénil, V. (eds.). Secondary Adaptations of Tetrapods to Life in the Water: Proceedings of the international meeting, Poitiers, 1996. München, Germany: Verlag Dr. Friedrich Pfeil. pp. 169–233. ISBN 3-931516-88-1. LCCN 2002550356. OCLC 52121251. OL 20591860M.
^M. Raneft, D.; Eaker, H.; W. Davis, R. (2001). "A guide to the pronunciation and meaning of cetacean taxonomic names" (PDF). Aquatic Mammals. 27 (2): 185. Archived (PDF) from the original on 2016-03-27.
^E. Fish, Frank (2002). "Balancing Requirements for Stability and Maneuverability in Cetaceans". Integrative and Comparative Biology. 42 (1): 85–93. doi:10.1093/icb/42.1.85. PMID 21708697. S2CID 25036870.
^Wood, Gerald The Guinness Book of Animal Facts and Feats (1983) ISBN 978-0-85112-235-9
^Davies, Ella (2016-04-20). "The longest animal alive may be one you never thought of". BBC Earth. Retrieved 2018-02-14.
^Notarbartolo di Sciara, G.; Briand, F. (2004). "Investigating the Roles of Cetaceans in Marine Ecosystems - An overview". CIESM Workshop Monographs. 25: 1–15.[1]
^Cara E. Miller (2007). Current State of Knowledge of Cetacean Threats, Diversity, and Habitats in the Pacific Islands Region(PDF). Whale and Dolphin Conservation Society. ISBN 978-0-646-47224-9. Archived from the original (PDF) on 8 September 2015. Retrieved 5 September 2015.
^Nowacek, Douglas; Donovan, Greg; Gailey, Glenn; Racca, Roberto; Reeves, Randall; Vedenev, Alexander; Weller, David; Southall, Brandon (2013). "Responsible Practices for Minimizing and Monitoring Environmental Impacts of Marine Seismic Surveys with an Emphasis on Marine Mammal". Aquatic Mammals. 39 (4): 356–377. doi:10.1578/am.39.4.2013.356.
^Lovgren, Stefan (December 14, 2006). "China's Rare River Dolphin Now Extinct, Experts Announce". National Geographic News. Washington, D.C.: National Geographic Society. Archived from the original on December 18, 2006. Retrieved 2015-10-18.
Cetacea (/sɪˈteɪʃə/; from Latin cetus 'whale', from Ancient Greek κῆτος (kêtos) 'huge fish, sea monster') is an infraorder of aquatic mammals belonging...
Cetacea is an infraorder that comprises the 94 species of whales, dolphins, and porpoises. It is divided into toothed whales (Odontoceti) and baleen whales...
Zalmout I.S. (2019). "Aegicetus gehennae, a new late Eocene protocetid (Cetacea, Archaeoceti) from Wadi Al Hitan, Egypt, and the transition to tail-powered...
Pangolins, sometimes known as scaly anteaters, are mammals of the order Pholidota (/fɒlɪˈdoʊtə/). The one extant family, the Manidae, has three genera:...
Cetacea Rocks (63°43′S 61°37′W / 63.717°S 61.617°W / -63.717; -61.617) are a small group of rocks off the northeast side of Hoseason Island, in the...
derived cognitive ability of aquatic mammals belonging in the infraorder Cetacea (cetaceans), including baleen whales, porpoises, and dolphins. In 2014...
present-extending Cenozoic Era. Molecular and morphological analyses suggest Cetacea share a relatively recent closest common ancestor with hippopotami and...
have been recovered from the formation, as well as other flora and fauna. Cetacea Pseudosuchians Snakes Turtles Datta, Debajit; Bajpai, Sunil (18 April 2024)...
address this problem, the traditional order Artiodactyla and infraorder Cetacea are sometimes subsumed into the more inclusive Cetartiodactyla taxon. An...
colloquial grouping, they correspond to large members of the infraorder Cetacea, i.e. all cetaceans apart from dolphins and porpoises. Dolphins and porpoises...
The Cetacean Conservation Center (Centro de Conservación Cetacea or CCC) is a Chilean NGO dedicated to the conservation of cetaceans and other marine...
taxa are separate orders. Molecular studies, however, have shown that the Cetacea descend from artiodactyl ancestors, although the precise phylogeny within...
Remingtonocetidae is a diverse family of early aquatic mammals of the order Cetacea. The family is named after paleocetologist Remington Kellogg. Remingtonocetids...
overwhelmingly supported an evolutionary relationship between Hippopotamidae and Cetacea. Modern Whippomorphs all share a number of behavioural and physiological...
observed members of the order Cetacea, including whales, dolphins and porpoises, show a range of surfacing behaviours. Cetacea is usually split into two suborders...
(2022). "A redescription and re-evaluation of Kekenodon onamata (Mammalia: Cetacea), a late-surviving archaeocete from the Late Oligocene of New Zealand"...
Landini, W. (2006). "Killer sperm whale: a new basal physeteroid (Mammalia, Cetacea) from the Late Miocene of Italy" (PDF). Zoological Journal of the Linnean...
Monodon monoceros, narwhal Bohaskaia monodontoides, a New Monodontid (Cetacea, Odontoceti, Delphinoidea) from the Pliocene of the Western North Atlantic...
extinct cetaceans features the extinct genera and species of the order Cetacea. The cetaceans (whales, dolphins and porpoises) are descendants of land-living...
nouveau Platanistidae Cetacea du Pliocene de la cote peruvienne" [Pliopontos littoralis nov. gen. nov. sp. a New Platanistidae (Cetacea) from the Pliocene...
former maintains precedent. Whippomorpha is the crown clade containing Cetacea (whales, dolphins, etc.) and hippopotamuses. Members of the whippomorph...
evolutionary history of flipper development and hyperphalangy in dolphins (Cetacea: Mammalia)", ResearchGate, doi: 10.1002/dvg.23076. October 2017 Mittra...
Balaenoptera (Cetacea: Mysticeti). Marine Mammal Science 2(4):277-298 M. Bosselaers and K. Post. 2010. A new fossil rorqual (Mammalia, Cetacea, Balaenopteridae)...
Cetacea) from Italian Pliocene. Systematics and Phylogenesis of Delphinidae". Palaeontographia Italica. 84: 97–98. Lydekker, R. (1887). "The Cetacea of...
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