62-486: See text Umbraculoidea is a superfamily of unusual false limpets with a thin soft patelliform shell, marine gastropod molluscs in the clade Umbraculida, within the clade Euopisthobranchia . There are two families in this superfamily, which is listed as the only superfamily in the clade Umbraculida within the informal group Opisthobranchia in the taxonomy of Bouchet & Rocroi (2005). A study by Grande et al. , published in 2004, concluded that Umbraculoidea
124-492: A BioCode that would regulate all taxon names, but this attempt has so far failed because of firmly entrenched traditions in each community. Consider a particular species, the red fox , Vulpes vulpes : in the context of the Zoological Code , the specific epithet vulpes (small v ) identifies a particular species in the genus Vulpes (capital V ) which comprises all the "true" foxes. Their close relatives are all in
186-567: A septum . Caniforms have single-chambered or partially divided auditory bullae, composed of a single bone. Initially, the early representatives of carnivorans were small as the creodonts (specifically, the oxyaenids) and mesonychians dominated the apex predator niches during the Eocene, but in the Oligocene, carnivorans became a dominant group of apex predators with the nimravids , and by the Miocene most of
248-420: A "hybrid formula" that specifies the parentage, or may be given a name. For hybrids receiving a hybrid name , the same ranks apply, prefixed with notho (Greek: 'bastard'), with nothogenus as the highest permitted rank. If a different term for the rank was used in an old publication, but the intention is clear, botanical nomenclature specifies certain substitutions: Classifications of five species follow:
310-440: A correlation between habitat and color pattern; for example spotted or banded species tend to be found in heavily forested environments. Some species like the grey wolf are polymorphic with different individual having different coat colors. The arctic fox ( Vulpes lagopus ) and the stoat ( Mustela erminea ) have fur that changes from white and dense in the winter to brown and sparse in the summer. In pinnipeds and polar bears ,
372-560: A fast evolutionary radiation that occurred long ago, such as the main taxa of placental mammals . In his landmark publications, such as the Systema Naturae , Carl Linnaeus used a ranking scale limited to kingdom, class, order, genus, species, and one rank below species. Today, the nomenclature is regulated by the nomenclature codes . There are seven main taxonomic ranks: kingdom, phylum or division, class, order, family, genus, and species. In addition, domain (proposed by Carl Woese )
434-638: A lower level may be denoted by adding the prefix " infra ", meaning lower , to the rank. For example, infra order (below suborder) or infra family (below subfamily). Botanical ranks categorize organisms based (often) on their relationships ( monophyly is not required by that clade, which does not even mention this word, nor that of " clade "). They start with Kingdom, then move to Division (or Phylum), Class, Order, Family, Genus, and Species. Taxa at each rank generally possess shared characteristics and evolutionary history. Understanding these ranks aids in taxonomy and studying biodiversity. There are definitions of
496-399: A new rank at will, at any time, if they feel this is necessary. In doing so, there are some restrictions, which will vary with the nomenclature code that applies. The following is an artificial synthesis, solely for purposes of demonstration of absolute rank (but see notes), from most general to most specific: Ranks are assigned based on subjective dissimilarity, and do not fully reflect
558-459: A particular organism, it is usually not necessary to specify names at ranks other than these first two, within a set of taxa covered by a given rank-based code. However, this is not true globally because most rank-based codes are independent from each other, so there are many inter-code homonyms (the same name used for different organisms, often for an animal and for a taxon covered by the botanical code). For this reason, attempts were made at creating
620-468: A supporting amount of evidence that Miacoidea is an evolutionary grade of carnivoramorphs that, while viverravids are monophyletic basal group, the miacids are paraphyletic in respect to Carnivora (as shown in the phylogeny below). Carnivoramorpha as a whole first appeared in the Paleocene of North America about 60 million years ago. Crown carnivorans first appeared around 42 million years ago in
682-576: A taxon in a category above the species level). It should be a natural group (that is, non-artificial, non- polyphyletic ), as judged by a biologist, using all the information available to them. Equally ranked higher taxa in different phyla are not necessarily equivalent in terms of time of origin, phenotypic distinctiveness or number of lower-ranking included taxa (e.g., it is incorrect to assume that families of insects are in some way evolutionarily comparable to families of mollusks). Of all criteria that have been advocated to rank taxa, age of origin has been
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#1733085436618744-442: A thick insulating layer of blubber helps maintain their body temperature. Carnivorans are arguably the group of mammals of most interest to humans. The dog is noteworthy for not only being the first species of carnivoran to be domesticated , but also the first species of any taxon. In the last 10,000 to 12,000 years, humans have selectively bred dogs for a variety of different tasks and today there are well over 400 breeds. The cat
806-624: A wide array of body plans, varying greatly in size and shape. Carnivora are divided into two suborders , the Feliformia , containing the true felids and several " cat -like" animals; and the Caniformia , containing the true canids and many " dog -like" animals. The feliforms include the Felidae , Viverridae , hyena , and mongoose families, the majority of which live only in the Old World; cats are
868-668: Is a table chart of the extant carnivoran families and number of extant species recognized by various authors of the first (2009 ) and fourth (2014 ) volumes of the Handbook of the Mammals of the World : The canine teeth are usually large, conical, thick and stress resistant. All of the terrestrial species of carnivorans have three incisors on each side of each jaw (the exception is the sea otter ( Enhydra lutris ) which only has two lower incisor teeth). The third molar has been lost. The carnassial pair
930-564: Is also called a binomial , that is, a two-term name. For example, the zoological name for the human species is Homo sapiens . This is usually italicized in print or underlined when italics are not available. In this case, Homo is the generic name and it is capitalized; sapiens indicates the species and it is not capitalized. While not always used, some species include a subspecific epithet. For instance, modern humans are Homo sapiens sapiens , or H. sapiens sapiens . In zoological nomenclature, higher taxon names are normally not italicized, but
992-479: Is an order of placental mammals that have specialized in primarily eating flesh, whose members are formally referred to as carnivorans . The order Carnivora is the sixth largest order of mammals, comprising at least 279 species on every major landmass and in a variety of habitats, ranging from the cold polar regions of Earth to the hyper-arid region of the Sahara Desert and the open seas. Carnivorans exhibit
1054-475: Is another domesticated carnivoran and it is today considered one of the most successful species on the planet, due to their close proximity to humans and the popularity of cats as pets. Many other species are popular, and they are often charismatic megafauna . Many civilizations have incorporated a species of carnivoran into their culture: a prominent example is the lion , viewed as a symbol of power and royalty in many societies. Yet many species such as wolves and
1116-428: Is made up of the fourth upper premolar and the first lower molar teeth. Like most mammals, the dentition is heterodont , though in some species, such as the aardwolf ( Proteles cristata ), the teeth have been greatly reduced and the cheek teeth are specialised for eating insects. In pinnipeds, the teeth are homodont as they have evolved to grasp or catch fish, and the cheek teeth are often lost. In bears and raccoons,
1178-462: Is not a requirement of the zoological and botanical codes. A classification in which all taxa have formal ranks cannot adequately reflect knowledge about phylogeny. Since taxon names are dependent on ranks in rank-based (Linnaean) nomenclature, taxa without ranks cannot be given names. Alternative approaches, such as phylogenetic nomenclature , as implemented under the PhyloCode and supported by
1240-435: Is now widely used as a fundamental rank, although it is not mentioned in any of the nomenclature codes, and is a synonym for dominion ( Latin : dominium ), introduced by Moore in 1974. A taxon is usually assigned a rank when it is given its formal name. The basic ranks are species and genus. When an organism is given a species name it is assigned to a genus, and the genus name is part of the species name. The species name
1302-402: Is the relative or absolute level of a group of organisms (a taxon ) in a hierarchy that reflects evolutionary relationships. Thus, the most inclusive clades (such as Eukarya and Opisthokonta ) have the highest ranks, whereas the least inclusive ones (such as Homo sapiens or Bufo bufo ) have the lowest ranks. Ranks can be either relative and be denoted by an indented taxonomy in which
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#17330854366181364-482: Is usually associated with a certain body plan , which is also, however, an arbitrary criterion. Enigmatic taxa are taxonomic groups whose broader relationships are unknown or undefined. (See Incertae sedis .) There are several acronyms intended to help memorise the taxonomic hierarchy, such as "King Phillip came over for great spaghetti". (See taxonomy mnemonic .) Carnivora Carnivora ( / k ɑːr ˈ n ɪ v ər ə / kar- NIH -vər-ə )
1426-762: The Botanical Code , the Prokaryotic Code , the Code for Viruses , the draft BioCode and the PhyloCode all recommend italicizing all taxon names (of all ranks). There are rules applying to the following taxonomic ranks in the International Code of Zoological Nomenclature : superfamily, family, subfamily, tribe, subtribe, genus, subgenus, species, subspecies. The International Code of Zoological Nomenclature divides names into "family-group names", "genus-group names" and "species-group names". The Code explicitly mentions
1488-477: The Cretaceous–Paleogene extinction event . These early ancestors of carnivorans would have resembled small weasel or genet -like mammals, occupying a nocturnal shift on the forest floor or in the trees, as other groups of mammals like the mesonychians and later the creodonts were occupying the megafaunal faunivorous niche. However, following the extinction of mesonychians and the oxyaenid creodonts at
1550-474: The International Society for Phylogenetic Nomenclature , or using circumscriptional names , avoid this problem. The theoretical difficulty with superimposing taxonomic ranks over evolutionary trees is manifested as the boundary paradox which may be illustrated by Darwinian evolutionary models. There are no rules for how many species should make a genus, a family, or any other higher taxon (that is,
1612-544: The Middle Eocene . Their molecular phylogeny shows the extant Carnivora are a monophyletic group, the crown group of the Carnivoramorpha . From there carnivorans have split into two clades based on the composition of the bony structures that surround the middle ear of the skull, the cat-like feliforms and the dog-like caniforms . In feliforms, the auditory bullae are double-chambered, composed of two bones joined by
1674-558: The PhyloCode , the code of phylogenetic nomenclature , does not require absolute ranks. Taxa are hierarchical groups of organisms, and their ranks describes their position in this hierarchy. High-ranking taxa (e.g. those considered to be domains or kingdoms, for instance) include more sub-taxa than low-ranking taxa (e.g. those considered genera, species or subspecies). The rank of these taxa reflects inheritance of traits or molecular features from common ancestors. The name of any species and genus are basic ; which means that to identify
1736-482: The big cats have been broadly hunted, resulting in extirpation in some areas. Habitat loss and human encroachment as well as climate change have been the primary cause of many species going into decline. Four species of carnivorans have gone extinct since the 1600s: Falkland Island wolf ( Dusicyon australis ) in 1876; the sea mink ( Neogale macrodon ) in 1894; the Japanese sea lion ( Zalophus japonicus ) in 1951 and
1798-427: The fruit fly familiar in genetics laboratories ( Drosophila melanogaster ), humans ( Homo sapiens ), the peas used by Gregor Mendel in his discovery of genetics ( Pisum sativum ), the "fly agaric" mushroom Amanita muscaria , and the bacterium Escherichia coli . The eight major ranks are given in bold; a selection of minor ranks are given as well. Taxa above the genus level are often given names based on
1860-418: The type genus , with a standard termination. The terminations used in forming these names depend on the kingdom (and sometimes the phylum and class) as set out in the table below. Pronunciations given are the most Anglicized . More Latinate pronunciations are also common, particularly / ɑː / rather than / eɪ / for stressed a . There is an indeterminate number of ranks, as a taxonomist may invent
1922-612: The American Ornithologists' Union published in 1886 states "No one appears to have suspected, in 1842 [when the Strickland code was drafted], that the Linnaean system was not the permanent heritage of science, or that in a few years a theory of evolution was to sap its very foundations, by radically changing men's conceptions of those things to which names were to be furnished." Such ranks are used simply because they are required by
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1984-406: The carnassial pair is secondarily reduced. The skulls are heavily built with a strong zygomatic arch . Often a sagittal crest is present, sometimes more evident in sexually dimorphic species such as sea lions and fur seals , though it has also been greatly reduced in some small carnivorans. The braincase is enlarged with the frontoparietal bone at the front. In most species, the eyes are at
2046-403: The clade Ferae . Ferae includes the closest extant relative of carnivorans, the pangolins , as well as several extinct groups of mostly Paleogene carnivorous placentals such as the creodonts , the arctocyonians , and mesonychians . The creodonts were originally thought of as the sister taxon to the carnivorans, perhaps even ancestral to, based on the presence of the carnassial teeth , but
2108-443: The dental and cranial features, not much of their overall anatomy unites carnivorans as a group. All species of carnivorans are quadrupedal and most have five digits on the front feet and four digits on the back feet. In terrestrial carnivorans, the feet have soft pads. The feet can either be digitigrade as seen in cats, hyenas and dogs or plantigrade as seen in bears, skunks, raccoons, weasels, civets and mongooses. In pinnipeds,
2170-477: The end of the Eocene, carnivorans quickly moved into this niche, with forms like the nimravids being the dominant large-bodied ambush predators during the Oligocene alongside the hyaenodont creodonts (which similarly produced larger, more open-country forms at the start of the Oligocene). By the time Miocene epoch appeared, most if not all of the major lineages and families of carnivorans had diversified and become
2232-745: The extant carnivoran families have diversified and become the primary terrestrial predators in the Northern Hemisphere. In 1758, the Swedish botanist Carl Linnaeus placed all carnivorans known at the time into the group Ferae (not to be confused with the modern concept of Ferae which also includes pangolins) in the tenth edition of his book Systema Naturae . He recognized six genera: Canis (canids and hyaenids), Phoca (pinnipeds), Felis (felids), Viverra (viverrids, herpestids, and mephitids), Mustela (non-badger mustelids), Ursus (ursids, large species of mustelids, and procyonids). It
2294-432: The family Canidae , which includes dogs, wolves, jackals, and all foxes; the next higher major taxon, Carnivora (considered an order), includes caniforms (bears, seals, weasels, skunks, raccoons and all those mentioned above), and feliforms (cats, civets, hyenas, mongooses). Carnivorans are one group of the hairy, warm-blooded, nursing members of the class Mammalia , which are classified among animals with notochords in
2356-595: The following ranks for these categories: The rules in the Code apply to the ranks of superfamily to subspecies, and only to some extent to those above the rank of superfamily. Among "genus-group names" and "species-group names" no further ranks are officially allowed, which creates problems when naming taxa in these groups in speciose clades, such as Rana . Zoologists sometimes use additional terms such as species group , species subgroup , species complex and superspecies for convenience as extra, but unofficial, ranks between
2418-461: The following taxonomic categories in the International Code of Nomenclature for Cultivated Plants : cultivar group , cultivar , grex . The rules in the ICN apply primarily to the ranks of family and below, and only to some extent to those above the rank of family. (See also descriptive botanical name .) Taxa at the rank of genus and above have a botanical name in one part (unitary name); those at
2480-407: The front of the face. In caniforms, the rostrum is usually long with many teeth, while in feliforms it is shorter with fewer teeth. The carnassial teeth of feliforms are generally more sectional than those of caniforms. The turbinates are large and complex in comparison to other mammals, providing a large surface area for olfactory receptors . Aside from an accumulation of characteristics in
2542-480: The gradational nature of variation within nature. These problems were already identified by Willi Hennig , who advocated dropping them in 1969, and this position gathered support from Graham C. D. Griffiths only a few years later. In fact, these ranks were proposed in a fixist context and the advent of evolution sapped the foundations of this system, as was recognised long ago; the introduction of The Code of Nomenclature and Check-list of North American Birds Adopted by
Umbraculoidea - Misplaced Pages Continue
2604-434: The hierarchy of taxa (hence, their ranks) does not necessarily reflect the hierarchy of clades . While older approaches to taxonomic classification were phenomenological, forming groups on the basis of similarities in appearance, organic structure and behavior, two important new methods developed in the second half of the 20th century changed drastically taxonomic practice. One is the advent of cladistics , which stemmed from
2666-496: The level of indentation reflects the rank, or absolute, in which various terms, such as species , genus , family , order , class , phylum , kingdom , and domain designate rank. This page emphasizes absolute ranks and the rank-based codes (the Zoological Code , the Botanical Code , the Code for Cultivated Plants , the Prokaryotic Code , and the Code for Viruses ) require them. However, absolute ranks are not required in all nomenclatural systems for taxonomists; for instance,
2728-407: The limbs have been modified into flippers . Unlike cetaceans and sirenians , which have fully functional tails to help them swim, pinnipeds use their limbs underwater to swim. Earless seals use their back flippers; sea lions and fur seals use their front flippers, and the walrus uses all of its limbs. As a result, pinnipeds have significantly shorter tails than other carnivorans. Aside from
2790-536: The methods in which mammalogists use to assess the phylogenetic relationships among the carnivoran families has been improved with using more complicated and intensive incorporation of genetics, morphology and the fossil record. Research into Carnivora phylogeny since 1945 has found Fisspedia to be paraphyletic in respect to Pinnipedia, with pinnipeds being either more closely related to bears or to weasels. The small carnivoran families Viverridae, Procyonidae, and Mustelidae have been found to be polyphyletic : Below
2852-405: The most basic (or important) is the species, but this opinion is not universally shared. Thus, species are not necessarily more sharply defined than taxa at any other rank, and in fact, given the phenotypic gaps created by extinction, in practice, the reverse is often the case. Ideally, a taxon is intended to represent a clade , that is, the phylogeny of the organisms under discussion, but this
2914-510: The most dominant group of large terrestrial predators in Eurasia and North America, with various lineages being successful in megafaunal faunivorous niches at different intervals during the Miocene and later epochs. The order Carnivora belongs to a group of mammals known as Laurasiatheria , which also includes other groups such as bats and ungulates . Within this group the carnivorans are placed in
2976-409: The most frequently advocated. Willi Hennig proposed it in 1966, but he concluded in 1969 that this system was unworkable and suggested dropping absolute ranks. However, the idea of ranking taxa using the age of origin (either as the sole criterion, or as one of the main ones) persists under the name of time banding, and is still advocated by several authors. For animals, at least the phylum rank
3038-442: The nature of the carnassial teeth is different between the two groups. In carnivorans the carnassials are positioned near the front of the molar row, while in the creodonts they are positioned near the back of the molar row, and this suggests a separate evolutionary history and an order-level distinction. In addition, recent phylogenetic analysis suggests that creodonts are more closely related to pangolins while mesonychians might be
3100-775: The only exception, occurring in the old world and the new world, entering the Americas via the Bering Land Bridge. The caniforms include the Caninae , Procyonidae , bears , mustelids , skunks and pinnipeds that occur worldwide with immense diversity in their morphology, diet and behavior. The word carnivore is derived from Latin carō (stem carn- ) 'flesh' and vorāre 'to devour', and refers to any meat-eating organism. The oldest known carnivoran line mammals ( Carnivoramorpha ) appeared in North America 6 million years after
3162-474: The phylum Chordata , and with them among all animals in the kingdom Animalia . Finally, at the highest rank all of these are grouped together with all other organisms possessing cell nuclei in the domain Eukarya . The International Code of Zoological Nomenclature defines rank as: "The level, for nomenclatural purposes, of a taxon in a taxonomic hierarchy (e.g. all families are for nomenclatural purposes at
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#17330854366183224-783: The pinnipeds, dogs, bears, hyenas, and cats all have distinct and recognizable appearances. Dogs are usually cursorial mammals and are gracile in appearance, often relying on their teeth to hold prey; bears are much larger and rely on their physical strength to forage for food. Compared to dogs and bears, cats have longer and stronger forelimbs armed with retractable claws to hold on to prey. Hyenas are dog-like feliforms that have sloping backs due to their front legs being longer than their hind legs. The raccoon family and red panda are small, bear-like carnivorans with long tails. The other small carnivoran families Nandiniidae , Prionodontidae , Viverridae , Herpestidae , Eupleridae, Mephitidae and Mustelidae have through convergent evolution maintained
3286-455: The rank of species and above (but below genus) have a botanical name in two parts ( binary name ); all taxa below the rank of species have a botanical name in three parts (an infraspecific name ). To indicate the rank of the infraspecific name, a "connecting term" is needed. Thus Poa secunda subsp. juncifolia , where "subsp". is an abbreviation for "subspecies", is the name of a subspecies of Poa secunda . Hybrids can be specified either by
3348-653: The rank-based codes; because of this, some systematists prefer to call them nomenclatural ranks . In most cases, higher taxonomic groupings arise further back in time, simply because the most inclusive taxa necessarily appeared first. Furthermore, the diversity in some major taxa (such as vertebrates and angiosperms ) is better known that that of others (such as fungi , arthropods and nematodes ) not because they are more diverse than other taxa, but because they are more easily sampled and studied than other taxa, or because they attract more interest and funding for research. Of these many ranks, many systematists consider that
3410-460: The same rank, which lies between superfamily and subfamily)." Note that the discussions on this page generally assume that taxa are clades ( monophyletic groups of organisms), but this is required neither by the International Code of Zoological Nomenclature nor by the Botanical Code , and some experts on biological nomenclature do not think that this should be required, and in that case,
3472-460: The sister group to carnivorans and their stem-relatives. The closest stem-carnivorans are the miacoids . The miacoids include the families Viverravidae and Miacidae , and together the Carnivora and Miacoidea form the stem-clade Carnivoramorpha . The miacoids were small, genet-like carnivoramorphs that occupy a variety of niches such as terrestrial and arboreal habitats. Recent studies have shown
3534-406: The small, ancestral appearance of the miacoids, though there is some variation seen such as the robust and stout physicality of badgers and the wolverine ( Gulo gulo ). Most carnivoran species have a well-defined breeding season . Male carnivorans usually have bacula , which are absent in hyenas and binturongs . The length and density of the fur vary depending on the environment that
3596-433: The species inhabits. In warm climate species, the fur is often short in length and lighter. In cold climate species, the fur is either dense or long, often with an oily substance that helps to retain heat. The pelage coloration differs between species, often including black, white, orange, yellow, red, and many shades of grey and brown. Some are striped, spotted, blotched, banded, or otherwise boldly patterned. There seems to be
3658-481: The subgenus and species levels in taxa with many species, e.g. the genus Drosophila . (Note the potentially confusing use of "species group" as both a category of ranks as well as an unofficial rank itself. For this reason, Alain Dubois has been using the alternative expressions "nominal-series", "family-series", "genus-series" and "species-series" (among others) at least since 2000. ) At higher ranks (family and above)
3720-723: The works of the German entomologist Willi Hennig . Cladistics is a method of classification of life forms according to the proportion of characteristics that they have in common (called synapomorphies ). It is assumed that the higher the proportion of characteristics that two organisms share, the more recently they both came from a common ancestor. The second one is molecular systematics, based on genetic analysis , which can provide much additional data that prove especially useful when few phenotypic characters can resolve relationships, as, for instance, in many viruses , bacteria and archaea , or to resolve relationships between taxa that arose in
3782-522: Was a sister clade to the Cephalaspidea ( Acteonoidea excluded). Umbraculoidea contains two families: Jörger et al. (2010) moved Umbraculoidea to the Euopisthobranchia. Taxonomic rank In biology , taxonomic rank (which some authors prefer to call nomenclatural rank because ranking is part of nomenclature rather than taxonomy proper, according to some definitions of these terms)
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#17330854366183844-481: Was not until 1821 that the English writer and traveler Thomas Edward Bowdich gave the group its modern and accepted name. Initially, the modern concept of Carnivora was divided into two suborders: the terrestrial Fissipedia and the marine Pinnipedia . Below is the classification of how the extant families were related to each other after American paleontologist George Gaylord Simpson in 1945: Since then, however,
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