Cetacea. Medical search

An order of wholly aquatic MAMMALS occurring in all the OCEANS and adjoining seas of the world, as well as in certain river systems. They feed generally on FISHES, cephalopods, and crustaceans. Most are gregarious and most have a relatively long period of parental care and maturation. Included are DOLPHINS; PORPOISES; and WHALES. (From Walker's Mammals of the World, 5th ed, pp969-70)

Artiodactyla is an order of mammals characterized by an even number of digits (two or four) on each foot, hooves as terminal appendages, and a specialized stomach for fermentative digestion, which includes taxonomic families such as Suidae, Cervidae, Bovidae, and Camelidae among others.

Mammals of the families Delphinidae (ocean dolphins), Iniidae, Lipotidae, Pontoporiidae, and Platanistidae (all river dolphins). Among the most well-known species are the BOTTLE-NOSED DOLPHIN and the KILLER WHALE (a dolphin). The common name dolphin is applied to small cetaceans having a beaklike snout and a slender, streamlined body, whereas PORPOISES are small cetaceans with a blunt snout and rather stocky body. (From Walker's Mammals of the World, 5th ed, pp978-9)

Large marine mammals of the order CETACEA. In the past, they were commercially valued for whale oil, for their flesh as human food and in ANIMAL FEED and FERTILIZERS, and for baleen. Today, there is a moratorium on most commercial whaling, as all species are either listed as endangered or threatened.

Mammals of the family Phocoenidae comprising four genera found in the North Pacific Ocean and both sides of the North Atlantic Ocean and in various other seas. They differ from DOLPHINS in that porpoises have a blunt snout and a rather stocky body while dolphins have a beak-like snout and a slender, streamlined body. They usually travel in small groups. (From Walker's Mammals of the World, 5th ed, pp1003-4)

The species Balaenoptera acutorostrata, in the family Balaenopteridae. It is the smallest of the WHALES in the family and though mainly oceanic, is often found in coastal waters including bays and estuaries.

Remains, impressions, or traces of animals or plants of past geological times which have been preserved in the earth's crust.

The relationships of groups of organisms as reflected by their genetic makeup.

The process of cumulative change over successive generations through which organisms acquire their distinguishing morphological and physiological characteristics.

Double-stranded DNA of MITOCHONDRIA. In eukaryotes, the mitochondrial GENOME is circular and codes for ribosomal RNAs, transfer RNAs, and about 10 proteins.

Fitzgerald factor (high molecular weight kininogen) clotting activity in human plasma in health and disease in various animal plasmas. (1/159)

Fitzgerald factor (high molecular weight kininogen) is an agent in normal human plasma that corrects the impaired in vitro surface-mediated plasma reactions of blood coagulation, fibrinolysis, and kinin generation observed in Fitzgerald trait plasma. To assess the possible pathophysiologic role of Fitzgerald factor, its titer was measured by a functional clot-promoting assay. Mean +/- SD in 42 normal adults was 0.99+/-0.25 units/ml, one unit being the activity in 1 ml of normal pooled plasma. No difference in titer was noted between normal men and women, during pregnancy, or after physical exercise. Fitzgerald factor activity was significantly reduced in the plasmas of eight patients with advanced hepatic cirrhosis (0.40+/-0.09 units/ml) and of ten patients with disseminated intravascular coagulation (0.60+/-0.30 units/ml), but was normal in plasmas of patients with other congenital clotting factor deficiencies, nephrotic syndrome, rheumatoid arthritis, systemic lupus erythematosus, or sarcoidosis, or under treatment with warfarin. The plasmas of 21 mammalian species tested appeared to contain Fitzgerald factor activity, but those of two avian, two repitilian, and one amphibian species did not correct the coagulant defect in Fitzgerald trait plasmas. (+info)

Purification and properties of whale thyroid-stimulating hormone III. Properties of isolated multiple components. (2/159)

Properties of the four purified components of whale thyroid-stimulating hormone (TSH) have been compared. The amino acid composition shows close similarity among these components. Their hexosamine and sialic acid contents are of the same magnitude, whereas the neutral sugar composition differs somewhat from each other. The molecular weight of whale TSH determined by sedimentation equilibrium is 29,000, and no difference in molecular weight as well as in Stokes radius as determined by gel filtration has been detected among these four components. The amino acid and carbohydrate compositions of whale TSH resemble those of TSH from other species, especially those of non-primate mammalian TSH. Whale TSH contains, unlike bovine TSH but like human TSH, 1-2 residues of sialic acid as a constituent carbohydrate. (+info)

Genealogy of families of SINEs in cetaceans and artiodactyls: the presence of a huge superfamily of tRNA(Glu)-derived families of SINEs. (3/159)

Several novel (sub)families of SINEs were isolated from the genomes of cetaceans and artiodactyls, and their sequences were determined. From comparisons of diagnostic nucleotides among the short interspersed repetitive elements (SINEs) in these (sub)families, we were able to draw the following conclusions. (1) After the divergence of the suborder Tylopoda (camels), the CHRS family of SINEs was newly created from tRNA(Glu) in a common ancestor of the lineages of the Suina (pigs and peccaries), Ruminantia (cows and deer), and Cetacea (whales and dolphins). (2) After divergence of the Suina lineage, the CHR-1 SINE and the CHR-2 SINE were generated successively in a common ancestor of ruminants, hippopotamuses, and cetaceans. (3) In the Ruminantia lineage, the Bov-tA SINE was generated by recombination between the CHR-2 SINE and Bov-A. (4) In the Suina lineage, the CHRS-S SINE was generated from the CHRS SINE. (5) In this latter lineage, the PRE-1 family of SINEs was created by insertion of part of the gene for tRNA(Arg) into the 5' region of the CHRS-S family. The distribution of a particular family of SINEs among species of artiodactyls and cetaceans confirmed the most recent conclusion for paraphyly of the order Artiodactyla. The present study also revealed that a newly created tRNA(Glu)-derived family of SINEs was subjected both to recombination with different units and to duplication of an internal sequence within a SINE unit to generate, during evolution, a huge superfamily of tRNA(Glu)-related families of SINEs that are now found in the genomes of artiodactyls and cetaceans. (+info)

A review of virus infections of cataceans and the potential impact of morbilliviruses, poxviruses and papillomaviruses on host population dynamics. (4/159)

Viruses belonging to 9 families have been detected in cetaceans. We critically review the clinical features, pathology and epidemiology of the diseases they cause. Cetacean morbillivirus (family Paramyxoviridae) induces a serious disease with a high mortality rate and persists in several populations. It may have long-term effects on the dynamics of cetacean populations either as enzootic infection or recurrent epizootics. The latter presumably have the more profound impact due to removal of sexually mature individuals. Members of the family Poxviridae infect several species of odontocetes, resulting in ring and tattoo skin lesions. Although poxviruses apparently do not induce a high mortality, circumstancial evidence suggests they may be lethal in young animals lacking protective immunity, and thus may negatively affect net recruitment. Papillomaviruses (family Papovaviridae) cause genital warts in at least 3 species of cetaceans. In 10% of male Burmeister's porpoises Phocoena spinipinnis from Peru, lesions were sufficiently severe to at least hamper, if not impede, copulation. Members of the families Herpesviridae, Orthomyxoviridae and Rhabdoviridae were demonstrated in cetaceans suffering serious illnesses, but with the exception of a 'porpoise herpesvirus' their causative role is still tentative. Herpes-like viruses and caliciviruses (Caliciviridae) give rise to cutaneous diseases in Monodontidae and Delphinidae. Antibodies to several serotypes of caliciviruses were found in odontocetes and mysticetes. An unrecognized Hepadnaviridae was detected by serology in a captive Pacific white-sided dolphin Lagenorhynchus obliquidens with chronic persistent hepatitis. Adenoviruses (Adenoviridae) were isolated from the intestinal tracts of mysticeti and a beluga Delphinapterus leucas but were not associated with any pathologies. We discuss the potential impact of Paramyxoviridae, Poxviridae and Papovaviridae on the dynamics of several odontocete populations. (+info)

Using protein structural information in evolutionary inference: transmembrane proteins. (5/159)

We present a model of amino acid sequence evolution based on a hidden Markov model that extends to transmembrane proteins previous methods that incorporate protein structural information into phylogenetics. Our model aims to give a better understanding of processes of molecular evolution and to extract structural information from multiple alignments of transmembrane sequences and use such information to improve phylogenetic analyses. This should be of value in phylogenetic studies of transmembrane proteins: for example, mitochondrial proteins have acquired a special importance in phylogenetics and are mostly transmembrane proteins. The improvement in fit to example data sets of our new model relative to less complex models of amino acid sequence evolution is statistically tested. To further illustrate the potential utility of our method, phylogeny estimation is performed on primate CCR5 receptor sequences, sequences of l and m subunits of the light reaction center in purple bacteria, guinea pig sequences with respect to lagomorph and rodent sequences of calcitonin receptor and K-substance receptor, and cetacean sequences of cytochrome b. (+info)

Model dependence of the phylogenetic inference: relationship among carnivores, Perissodactyls and cetartiodactyls as inferred from mitochondrial genome sequences. (6/159)

Some previous analysis of mitochondrial proteins strongly support the Carnivora/Perissodactyla grouping excluding Cetartiodactyla (Artiodactyla + Cetacea) as an outgroup, but the support of the hypothesis remains equivocal from the analysis of several nuclear-encoded proteins. In order to evaluate the strength of the support by mitochondrial proteins, phylogenetic relationship among Carnivora, Perissodactyla, and Cetartiodactyla was estimated with the ML method by using the updated data set of the 12 mitochondrial proteins with several alternative models. The analyses demonstrate that the phylogenetic inference depends on the model used in the ML analysis; i.e., whether the site-heterogeneity is taken into account and whether the rate parameters are estimated for each individual proteins or for the concatenated sequences. Although the analysis of concatenated sequences strongly supports the Carnivora/Perissodactyla grouping, the total evaluation of the separate analyses of individual proteins, which approximates the data better than the concatenated analysis, gives only ambiguous results, and therefore it is concluded that more data are needed to resolve this trichotomy. (+info)

Elemental analysis of cetacean skull lesions associated with nematode infections. (7/159)

The elemental composition of both healthy and eroded cetacean skulls associated with nematode infections was evaluated. A total of 27 samples of eroded and non-eroded prepared museum cetacean skulls were characterised by elemental (CHN), X-ray fluorescence, and X-ray diffraction methods. The inorganic composition and crystal line structure (hydroxylapatite-like minerals) were similar for both types of skull samples, but the CHN values clearly differed. The results suggest that the carbon-rich fraction is lost in eroded areas, probably as a result of glycosaminoglycan-degrading Crassicauda enzymes. (+info)

Consistency of SINE insertion topology and flanking sequence tree: quantifying relationships among cetartiodactyls. (8/159)

Short interspersed nuclear elements (SINEs) have been used to generate unambiguous phylogenetic topologies relating eukaryotic taxa. The irreversible nature of SINE retroposition is supported by a large body of comparative genome data and is a fundamental assumption inherent in the value of this qualitative method of inference. Here, we assess the key assumption of unidirectional SINE insertion by comparing the SINE insertion-derived topology and the phylogenetic tree based on seven independent loci of five taxa in the order Cetartiodactyla (Cetacea + Artiodactyla). The data sets and analyses were largely independent, but the loci were, by definition, linked, and thus their consistency supported an irreversible pattern of SINE retroposition. Moreover, our analyses of the flanking sequences provided estimates of divergence times among cetartiodactyl lineages unavailable from SINE insertion analysis alone. Unexpected rate heterogeneity among sites of SINE-flanking sequences and other noncoding DNA sequences were observed. Sequence simulations suggest that this rate heterogeneity may be an artifact resulting from the inaccuracies of the substitution model used. (+info)

Cetacea is a taxonomic order that includes whales, dolphins, and porpoises. This group of marine mammals is characterized by their fully aquatic lifestyle, torpedo-shaped bodies, modified limbs that serve as flippers, and the absence of external hindlimbs. Cetaceans have streamlined bodies that minimize drag while swimming, and their tail flukes enable powerful propulsion through vertical movement in the water column.

Their respiratory system features a pair of blowholes on the top of their heads, which they use to breathe air at the surface. Cetaceans exhibit complex social behaviors, advanced communication skills, and sophisticated echolocation abilities for navigation and hunting. They primarily feed on fish and invertebrates, with some larger species preying on marine mammals.

Cetaceans have a global distribution, occupying various habitats such as open oceans, coastal areas, and rivers. Unfortunately, many cetacean populations face threats from human activities like pollution, habitat degradation, climate change, and direct hunting or bycatch in fishing gear. Conservation efforts are crucial to protect these remarkable creatures and their vital roles in marine ecosystems.

Artiodactyla is an order of mammals that includes even-toed ungulates, or hooved animals, with an odd number of toes. This group includes animals such as pigs, peccaries, hippos, camels, deer, giraffes, antelopes, and ruminants like cattle, sheep, and goats. The primary identifying feature of Artiodactyls is the presence of a pair of weight-bearing toes located in the middle of the foot, with the other toes being either reduced or absent. This arrangement provides stability and adaptability for these animals to thrive in various habitats worldwide.

"Dolphins" is a common name that refers to several species of marine mammals belonging to the family Delphinidae, within the larger group Cetacea. Dolphins are known for their intelligence, social behavior, and acrobatic displays. They are generally characterized by a streamlined body, a prominent dorsal fin, and a distinctive "smiling" expression created by the curvature of their mouths.

Although "dolphins" is sometimes used to refer to all members of the Delphinidae family, it is important to note that there are several other families within the Cetacea order, including porpoises and whales. Therefore, not all small cetaceans are dolphins.

Some examples of dolphin species include:

1. Bottlenose Dolphin (Tursiops truncatus) - This is the most well-known and studied dolphin species, often featured in aquariums and marine parks. They have a robust body and a prominent, curved dorsal fin.
2. Common Dolphin (Delphinus delphis) - These dolphins are characterized by their hourglass-shaped color pattern and distinct, falcate dorsal fins. There are two subspecies: the short-beaked common dolphin and the long-beaked common dolphin.
3. Spinner Dolphin (Stenella longirostris) - Known for their acrobatic behavior, spinner dolphins have a slender body and a long, thin beak. They are named for their spinning jumps out of the water.
4. Risso's Dolphin (Grampus griseus) - These dolphins have a unique appearance, with a robust body, a prominent dorsal fin, and a distinctive, scarred skin pattern caused by social interactions and encounters with squid, their primary food source.
5. Orca (Orcinus orca) - Also known as the killer whale, orcas are the largest dolphin species and are highly intelligent and social predators. They have a distinctive black-and-white color pattern and a prominent dorsal fin.

In medical terminology, "dolphins" do not have a specific relevance, but they can be used in various contexts such as therapy, research, or education. For instance, dolphin-assisted therapy is an alternative treatment that involves interactions between patients and dolphins to improve psychological and physical well-being. Additionally, marine biologists and researchers study dolphin behavior, communication, and cognition to understand their complex social structures and intelligence better.

I believe there may be some confusion in your question. Whales are not a medical term but rather large marine mammals. They belong to the Cetacean family, which includes dolphins and porpoises. If you're asking about a medical condition or something similar that might be associated with the word "whales," I would need more information to provide an accurate response.

I'm sorry for any confusion, but "porpoises" are not a medical term. They refer to a group of marine mammals that are closely related to dolphins. If you have any questions about medical terminology or concepts, I would be happy to help clarify those for you!

A Minke Whale is not a medical term. It is a type of baleen whale, which is one of the two major groups of whales and dolphins, the other being the toothed whales. There are two species of minke whales: the common minke whale (Balaenoptera acutorostrata) and the Antarctic minke whale (Balaenoptera bonaerensis). They are relatively small oceanic creatures, with a robust body and a pointed head. The common minke whale is found in both hemispheres, while the Antarctic minke whale is found only in the Southern Ocean.

Minke whales are not typically associated with medical definitions or terminology, unless in the context of a medical condition affecting the species or its population, such as a disease outbreak or injury.

In medical terms, "fossils" do not have a specific or direct relevance to the field. However, in a broader scientific context, fossils are the remains or impressions of prehistoric organisms preserved in petrified form or as a mold or cast in rock. They offer valuable evidence about the Earth's history and the life forms that existed on it millions of years ago.

Paleopathology is a subfield of paleontology that deals with the study of diseases in fossils, which can provide insights into the evolution of diseases and human health over time.

Phylogeny is the evolutionary history and relationship among biological entities, such as species or genes, based on their shared characteristics. In other words, it refers to the branching pattern of evolution that shows how various organisms have descended from a common ancestor over time. Phylogenetic analysis involves constructing a tree-like diagram called a phylogenetic tree, which depicts the inferred evolutionary relationships among organisms or genes based on molecular sequence data or other types of characters. This information is crucial for understanding the diversity and distribution of life on Earth, as well as for studying the emergence and spread of diseases.

Biological evolution is the change in the genetic composition of populations of organisms over time, from one generation to the next. It is a process that results in descendants differing genetically from their ancestors. Biological evolution can be driven by several mechanisms, including natural selection, genetic drift, gene flow, and mutation. These processes can lead to changes in the frequency of alleles (variants of a gene) within populations, resulting in the development of new species and the extinction of others over long periods of time. Biological evolution provides a unifying explanation for the diversity of life on Earth and is supported by extensive evidence from many different fields of science, including genetics, paleontology, comparative anatomy, and biogeography.

Mitochondrial DNA (mtDNA) is the genetic material present in the mitochondria, which are specialized structures within cells that generate energy. Unlike nuclear DNA, which is present in the cell nucleus and inherited from both parents, mtDNA is inherited solely from the mother.

MtDNA is a circular molecule that contains 37 genes, including 13 genes that encode for proteins involved in oxidative phosphorylation, a process that generates energy in the form of ATP. The remaining genes encode for rRNAs and tRNAs, which are necessary for protein synthesis within the mitochondria.

Mutations in mtDNA can lead to a variety of genetic disorders, including mitochondrial diseases, which can affect any organ system in the body. These mutations can also be used in forensic science to identify individuals and establish biological relationships.

Wikispecies has information related to Cetacea. Wikimedia Commons has media related to Cetacea. Cetacea at Wikibooks "Cetacea ... Cetacea's presumed location within Artiodactyla can be represented in the following cladogram: Within Cetacea, the two ... Cetacea) and the Minke Whale Balaenoptera acutorostrata (Balaenopteridae, Cetacea)". The Anatomical Record. 296 (2): 257-272. ... Cetacea are deliberate breathers who must be awake to inhale and exhale. When stale air, warmed from the lungs, is exhaled, it ...

https://en.wikipedia.org/wiki/Cetacea

... (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 ... This article incorporates public domain material from "Cetacea Rocks". Geographic Names Information System. United States ... and named by the UK Antarctic Place-Names Committee in 1960 after the zoological order Cetacea (whales and porpoises); these ...

https://en.wikipedia.org/wiki/Cetacea_Rocks

Deméré, T. A.; Berta, A. (2008). "Skull anatomy of the Oligocene toothed mysticete Aetioceus weltoni (Mammalia; Cetacea): ... Cetacea; Mysticeti) from western North America and Japan". The Island Arc. 3 (4): 392-431. doi:10.1111/j.1440-1738.1994.tb00122 ...

https://en.wikipedia.org/wiki/Ashorocetus

"Cetacea". American Society of Composers, Authors and Publishers. Retrieved September 2, 2017. Isobel (CD1) (CD liner notes). ...

https://en.wikipedia.org/wiki/List_of_songs_recorded_by_Björk

Aguayo-Lobo, A.; Torres Navarro, D.; Acevedo Ramírez, J. (1998). "Los Mamíferos Marinos de Chile: 1. Cetacea = Marine Mammals ... Gaskin, D. E. (1968). "Distribution of Delphinidae (Cetacea) in relation to sea surface temperatures off Eastern and Southern ... Lillie, D. G. (1915). "Cetacea. British Antarctic ("Terra Nova") Expedition, 1910". Zoology, British Museum (Natural History). ... Crovetto, A.; Lamilla, J.; Pequeño, G. (1992). "Lissodelphis peronii, Lacépède 1804 (Delphinidae, Cetacea) within the stomach ...

https://en.wikipedia.org/wiki/Southern_right_whale_dolphin

Cetacea; Mysticeti) from western North America and Japan". The Island Arc. 3 (4): 392-431. doi:10.1111/j.1440-1738.1994.tb00122 ...

https://en.wikipedia.org/wiki/Morawanocetus

Mammalia, Cetacea), from the middle Eocene of Egypt: clinorhynchy, olfaction, and hearing in a protocetid whale". Journal of ... ISBN 978-1-84028-152-1. Gingerich P.D. (2010). "Cetacea". In Werdelin L & Sanders W.J. (eds.). Cenozoic mammals of africa. ... Cetacea) from the middle Eocene Domanda Formation of the Sulaiman Range, Punjab (Pakistan)". Contributions from Museum of ...

https://en.wikipedia.org/wiki/Protocetus

Dolphin is a common name for aquatic mammals within the infraorder Cetacea. The term dolphin usually refers to the extant ... Baleen whales, (systematic name Mysticeti, form a parvorder of the Cetacea. They are a widely distributed group of carnivorous ... "Cetacea". Mammalogy: Adaptation, Diversity, Ecology. Johns Hopkins University Press. ISBN 978-1-4214-1588-8. "Fin whale". World ...

https://en.wikipedia.org/wiki/Physiology_of_underwater_diving

"Cetacea". iwcoffice.org. Archived from the original on 27 July 2012. "Cetacea". iwc.int. "Almost Saving Whales: The Ambiguity ...

https://en.wikipedia.org/wiki/International_Convention_for_the_Regulation_of_Whaling

Cetacea. 17: 165-73.{{cite journal}}: CS1 maint: multiple names: authors list (link) "Nearly 200 stranded pilot whales die on ... Kapel, F.O. (1975). "Preliminary notes on the occurrence and exploitation of smaller Cetacea in Greenland". J. Fish. Res. Board ...

https://en.wikipedia.org/wiki/Pilot_whale

Lillie, D. G. (1910). "Observations on the Anatomy and General Biology of some Members of the Larger Cetacea". Proceedings of ... Lillie, D. G. (1915). "Cetacea. British Antarctic ("Terra Nova") Expedition, 1910 British Museum (Natural History)". Natural ... Lillie, D. G. (1915). "Cetacea. British Antarctic ("Terra Nova") Expedition, 1910 British Museum (Natural History)". Natural ...

https://en.wikipedia.org/wiki/Denis_G._Lillie

Fitzgerald, Erich M. G. (2006). "A bizarre new toothed mysticete (Cetacea) from Australia and the early evolution of baleen ... ISBN 978-0-89599-014-3. Gatesy, J. (1997). "More DNA support for a Cetacea/Hippopotamidae clade: the blood-clotting protein ... ISBN 978-1-4398-4257-7. Fitzgerald, Erich M.G. (2010). "The morphology and systematics of Mammalodon colliveri (Cetacea: ... Feldhamer, George A.; Drickamer, Lee; Vessey, Stephen C.; Merritt, Joseph H.; Krajewski, Carey F. (2015). "Cetacea". Mammalogy ...

https://en.wikipedia.org/wiki/Baleen_whale

Shipps, B. K.; Peredo, C. M.; Pyenson, N. D. (2019). "Borealodon osedax, a new stem mysticete (Mammalia, Cetacea) from the ... Peredo, C. M.; Uhen, M. D. (2016-11-01). "A new basal chaeomysticete (Mammalia: Cetacea) from the Late Oligocene Pysht ... Cetacea; Mysticeti) from western North America and Japan". Island Arc. 3 (4): 392-431. doi:10.1111/j.1440-1738.1994.tb00122.x. ...

https://en.wikipedia.org/wiki/Klallamornis

Piscivory, or a diet based solely on fish, is likely the primitive condition for Cetacea, and it seems most parsimonious that ... Fitzgerald, E.M.G. (2006). "A bizarre new toothed mysticete (Cetacea) from Australia and the early evolution of baleen". ... Geisler and Sanders' 2003 paper, "Morphological Evidence for the Phylogeny of Cetacea" used the genus in their morphological ... Geisler, J.H.; Sanders, A. E. (2003). "Morphological evidence for the phylogeny of Cetacea". Journal of Mammalian Evolution. 10 ...

https://en.wikipedia.org/wiki/Aetiocetus

Classification and distribution of Oligocene Aetiocetidae (Mammalia; Cetacea; Mysticeti) from western North America and Japan. ...

https://en.wikipedia.org/wiki/Fucaia

2005). "Order Cetacea". Mammal Species of the World: A Taxonomic and Geographic Reference. Johns Hopkins University Press. pp. ... "Introduction to Cetacea: Archaeocetes: The Oldest Whales". University of Berkeley. Retrieved 25 July 2015. "Mysticetes hunt in ... Whales do not form a clade or order; the infraorder Cetacea includes dolphins and porpoises, which are not considered whales in ... As an informal and colloquial grouping, they correspond to large members of the infraorder Cetacea, i.e. all cetaceans apart ...

https://en.wikipedia.org/wiki/Whale