Cetacea

Also known as Cetaceans, cetaceans

Cetaceans are marine mammals belonging to the infraorder Cetacea (), a secondarily aquatic clade under the order Artiodactyla that include whales, dolphins, porpoises and extinct groups such as Basilosaurus. Most cetaceans live in marine environments, particularly the pelagic zone, but some reside solely in brackish or fresh water. Having a cosmopolitan distribution, they can be found in some rivers and all of Earth's oceans. Many species migrate seasonally over vast ranges for food advantages.

OverviewAI-generated

Cetacea is an infraorder within the class Mammalia, belonging to the phylum Chordata and kingdom Animalia. The taxon was described by Brisson in 1762 and falls under the order Cetartiodactyla. Common names for this group include whales, dolphins, and porpoises. The taxon has been recognized since approximately 50 million years ago, during the Eocene epoch.

Members of this group inhabit marine, brackish, and freshwater bodies of water. Their primary food source is zooplankton, and they are characterized by cetacean intelligence. The taxon is the source of whale oil and includes whales as a part. The study of these animals is known as cetology.

Scientific nomenclature for Cetacea is governed by the International Code of Zoological Nomenclature. The taxon is accepted in the World Register of Marine Species. It has been described in sources such as the Brockhaus and Efron Encyclopedic Dictionary and the Encyclopædia Britannica 11th edition.

Synthesized by Vinony from 49 facts across 8 sources: Wikidata, GBIF, PubMed, iNaturalist, Gbif Occ, WoRMS, iDigBio, Vinony graph. Generated from structured data (not the Wikipedia text) and checked against those facts — may still contain errors.

Species

whales, dolphins and porpoises

Cetacea

ORDER

KingdomAnimalia
PhylumChordata
ClassMammalia
OrderCetacea

Habitatmarine, brackish, freshwater

Observations0

Observations recorded3,161,144

賞鯨, 瓦尔德斯半岛 (阿根廷) 鲸下目（学名：Cetacea）旧称鲸目，是偶蹄目的演化支之一，包含了大约八十种大型的有胎盘海洋哺乳動物，即鯨魚﹑海豚和鼠海豚。鲸下目的现存物种可分为两个小目：须鲸（Mysticeti）和齿鲸（Odontoceti）。根據化石相關資料，鲸魚和陸生哺乳動物(河馬)有共同的祖先，是五千萬年前的海洋動物。遠古鯨魚擁有四肢及尾巴，與爬行哺乳類無異。現今鲸魚為哺乳動物中最適應水中生活者，體形成流線型，前肢為鰭，後肢已退化，後肢與脊椎骨並不相連且隱入身體內。鲸下目中的一些動物以其高智商（英语：Cetacean intelligence）聞名。美國科學促進會2012年在加拿大溫哥華的大會中，與會者重申對於鯨類動物權利法案的支持，此權利法案將鯨類動物列為「非人類的人」（non-human persons）。鯨類動物一胎只有一隻，生長期長，又因為其經濟價值遭到人類獵殺，2008年的研究指出四分之一的鲸鱼及海豚受到绝种威胁，其中有9个品种已經到濒危或极度濒危的程度。

via GBIF

Museum specimens

Specimen records: 7,328
With media: 341
Collections: USNM
Recorded in: United States

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Research

11,880 papers

Meta-analysis of the Cetacea gut microbiome: Diversity, co-evolution, and interaction with the anthropogenic pathobiome.The Science of the total environment · 2024Radaelli E, Palladino G, Nanetti E et al.DOI: 10.1016/j.scitotenv.2024.172943
Molecular evolution tracks macroevolutionary transitions in Cetacea.ReviewTrends in ecology & evolution · 2014McGowen MR, Gatesy J, Wildman DEDOI: 10.1016/j.tree.2014.04.001
Alterations of pleiotropic neuropeptide-receptor gene couples in Cetacea.BMC biology · 2024Valente R, Cordeiro M, Pinto B et al.DOI: 10.1186/s12915-024-01984-0
Research on whales, dolphins, and porpoises.Integrative zoology · 2021Li S, Liu MDOI: 10.1111/1749-4877.12565
Cetaceans.ReviewScience (New York, N.Y.) · 1989Würsig BDOI: 10.1126/science.2662403
Cetacea are natural knockouts for IL20.Immunogenetics · 2018Lopes-Marques M, Machado AM, Barbosa S et al.DOI: 10.1007/s00251-018-1071-5
Aggressive behavior in Cetacea.ReviewUCLA forum in medical sciences · 1967Norris KS
More DNA support for a Cetacea/Hippopotamidae clade: the blood-clotting protein gene gamma-fibrinogen.Molecular biology and evolution · 1997Gatesy JDOI: 10.1093/oxfordjournals.molbev.a025790

via PubMed

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Encyclopedic overview

58 sections

Contents

Etymology
Baleen whales and toothed whales
Anatomy
Head
Skeleton
Fluke
Physiology
Brain
Senses
Vision
Chemical senses
Electroreception
Echolocation
Ears
Circulation
Respiration
Abdominal organs
Chromosomes
Ecology
Range and habitat
Whale migration
Behaviour
Sleep
Diving
Social relations
Whale song
Hunting
Intelligence
Decision-making
Life history
Reproduction and brooding
Suckling
Lifespan
Death
Disease
Evolution
Fossil history
Origins
Transition from land to sea
Marine animals
External phylogeny
Internal phylogeny
Threats
Whaling
Fishing
Strandings
Environmental hazards
Relationship to humans
Research history
Culture
Middle Ages to the 19th century
Modern culture
Captivity
Belugas
Orcas
Others
References
External links

Key characteristics of cetaceans are their fully aquatic life cycle, streamlined, fish-like body shape, the need to periodically surface and breathe air, and exclusively carnivorous diet. All extant cetaceans are capable of echolocation.

Excerpted from Wikipedia’s “Cetacea” article, available under the CC BY-SA 4.0 licence.