|All extant caniform families (clockwise from top left): Canidae, Ursidae, Procyonidae, Mustelidae, Otariidae, Phocidae, Odobenidae, Mephitidae, Ailuridae|
|Suborder:|| Caniformia |
Caniformia is a suborder within the order Carnivora consisting of "dog-like" carnivorans. They include dogs, bears, wolves, foxes, raccoons, badgers, seals and mustelids.The Pinnipedia (seals, walruses and sea lions) are also assigned to this group. The center of diversification for Caniformia is North America and northern Eurasia. Caniformia stands in contrast to the other suborder of Carnivora, Feliformia ("cat-like" carnivorans), the center of diversification of which was in Africa and southern Asia.
Most members of this group have non-retractile claws (the fisher,marten, red panda, and ringtail have retractile or semi-retractile claws ) and tend to be plantigrade (with the exception of the Canidae). Other traits that separate Caniformia from Feliformia is that caniforms have longer jaws and have more teeth, with less specialized carnassial teeth. They also tend more towards omnivory and opportunistic feeding, while the feliforms, other than the viverrids, are more specialized for eating meat. Caniforms have single-chambered or partially divided auditory bullae, composed of a single bone, while in feliforms, the auditory bullae are double-chambered, composed of two bones joined by a septum. In the Canoidea, the bulbourethral glands and vesicula seminalis are always absent. Relative to body size, the baculum is usually longer in the Canoidea than in the Feloidea.
Caniformia consists of nine extant families, with three extinct families also recognized. The extant families are monophyletic according to phylogenetic molecular analysis.At one time, the Hyaenidae (hyenas) were included, but genetic testing has shown them to belong in Feliformia, instead. Terrestrial caniforms in the wild are found on all continents with the exception of Antarctica, while pinnipeds are distributed throughout the world's oceans.
Family Canidae (dogs and other canids) includes wolves, dogs, coyotes, and foxes, as well as a number of less familiar animals. The family is currently divided into two major groups, the true dogs (tribe Canini), which includes nine genera, and the true foxes (tribe Vulpini) with two genera. In addition, two basal genera are described. About 35 species of extant canids are currently recognized. Canids are the most social of all caniforms, sometimes living in packs. The dog is the most diverse of all mammals in terms of body structure variants.[ citation needed ]
Family Ursidae (bears) is the largest of all the land caniforms. Eight species are recognized, divided into five genera. They range from the large polar bear (males, 350–680+ kg or 775-1500+ lb) to the small sun bear (males, 30–60 kg or 66–132 lb) and from the endangered giant panda to the very common black bear. Common characteristics of modern bears include a large body with stocky legs, a long snout, shaggy hair, plantigrade paws with five nonretractile claws, and a short tail. Most bears are omnivorous, with largely varied diets that include both plants and animals. The polar bear is the most carnivorous of bears due to the arctic climate in which it lives, and shows a preference for eating seals. The giant panda is the most herbivorous bear and has evolved a number of adaptations, including a sixth "toe", specialized teeth, and strong jaw muscles, to allow it to feed nearly exclusively on bamboo, a tough member of the grass family. The sloth bear has some adaptations for ant and termite eating, with a long snout, powerful claws, and missing upper front teeth, though it also eats honey and fruit.
Family Ailuridae consists today of a single species, the red panda, which was once thought to be included in the Procyonidae or Ursidae lineages, but is now placed in its own family along with a number of extinct species. It is found in the Himalayas, including southern China, Nepal, Bhutan, India, and Pakistan. Fossil species of the family are also found in North America.
Family Mephitidae (skunks and stink badgers) was once classified as mustelids, but are now recognized as a lineage in their own right. The 12 species of skunks are divided into four genera: Mephitis (hooded and striped skunks, two species), Spilogale (spotted skunks, four species), Mydaus (stink badgers, two species) and Conepatus (hog-nosed skunks, four species). The two skunk species in the genus Mydaus inhabit Indonesia and the Philippines; all other skunks inhabit the Americas from Canada to central South America.
Family Mustelidae (badgers, weasels and otters) is the largest family of carnivora, with 22 extant genera and roughly 57 extant species. While highly variable in shape, size, and behavior, most mustelids are smaller animals with short legs, short, round ears, and thick fur. Mustelids are predominantly carnivorous. While not all share identical dentition, they all possess teeth adapted for eating flesh, including the presence of shearing carnassials.
Members of Family Procyonidae (raccoons, coatis) are smallish animals, with generally slender bodies and long tails. Nineteen extant species in six genera are currently recognized. Except for the kinkajou, all procyonids have banded tails and distinct facial markings, and like bears, are plantigrade, walking on the soles of their feet. Most species have nonretractile claws. Early procyonids may have been an offshoot of the canids that adapted to more omnivorous diets.
Pinnipedia (seals, sea lions, and walruses clade) is a widely distributed and diverse group of semiaquatic marine mammals which is closely related to an extinct group of pinnipeds, Enaliarctos. While support for the monophyly of pinnipeds is strong, the relationship of pinnipeds to terrestrial mammals is still unclear. Some studies support the hypothesis that the bears are their closest relatives,while others support a closer relationship to the mustelids.
Pinnipeds split from other caniforms 50 million years ago (mya) during the Eocene.
The clade is currently divided into three families:
Caniforms first appeared as tree-climbing, superficially marten-like carnivores in the Eocene around 42 million years ago. Miacis cognitus was probably an early caniform. Like many other early carnivorans, it was well suited for tree climbing with needle-sharp claws, and had limbs and joints that resemble those of modern carnivorans. M. cognitus was probably a very agile forest dweller that preyed on smaller animals, such as small mammals, reptiles, and birds.
Debate continues on the origin of pinnipeds. Recent molecular evidence suggests pinnipeds evolved from a bear-like ancestor about 23 million years ago during the late Oligocene or early Miocene epochs, a transitional period between the warmer Paleogene and cooler Neogene periods.However, discovery of the fossil Puijila darwini in early Miocene deposits in Nunavut suggests a different scenario. Like a modern otter, Puijila had a long tail, short limbs, and webbed feet instead of flippers. However, its limbs and shoulders were more robust, and Puijila likely had been a quadrupedal swimmer–retaining a form of aquatic locomotion that give rise to the major swimming types employed by modern pinnipeds. Puijila has been assigned to a clade of mustelids.
The cladogram is based on molecular phylogeny of six genes in Flynn, 2005.
Bears are carnivoran mammals of the family Ursidae. They are classified as caniforms, or doglike carnivorans. Although only eight species of bears are extant, they are widespread, appearing in a wide variety of habitats throughout the Northern Hemisphere and partially in the Southern Hemisphere. Bears are found on the continents of North America, South America, Europe, and Asia. Common characteristics of modern bears include large bodies with stocky legs, long snouts, small rounded ears, shaggy hair, plantigrade paws with five nonretractile claws, and short tails.
Carnivora is an order of placental mammals that have specialized in primarily eating flesh. Its members are formally referred to as carnivorans, though some species are omnivorous, such as raccoons and bears, and quite a few species such as pandas are specialized herbivores. The word 'carnivore' is derived from Latin carō "flesh" and vorāre "to devour", it refers to any meat-eating organism. The order Carnivora is the fifth largest order of mammals and one of the more successful members of the group; it comprises at least 279 species living on every major landmass and in a variety of habitats, ranging the cold polar regions to the hyper-arid region of the Sahara Desert to the open seas. They come in a huge array of different body plans in contrasting shapes and sizes. The smallest carnivoran is the least weasel with a body length of about 11 cm (4.3 in) and a weight of about 25 g (0.88 oz). The largest is the southern elephant seal, with adult males weighing up to 5,000 kg (11,000 lb) and measuring up to 6.7 m (22 ft). All species of carnivorans are descended from a group of mammals which were related to today's pangolins, having appeared in North America 6 million years after 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 creodonts were occupying the top faunivorous niche. However, by the time Miocene epoch appeared, most if not all of the major lineages and families of carnivorans had diversified and took over this niche.
The Mustelidae are a family of carnivorous mammals, including weasels, badgers, otters, ferrets, martens, minks, and wolverines, among others. Mustelids are a diverse group and form the largest family in the order Carnivora, suborder Caniformia. Mustelidae comprises about 56–60 species across eight subfamilies.
Pinnipeds, commonly known as seals, are a widely distributed and diverse clade of carnivorous, fin-footed, semiaquatic marine mammals. They comprise the extant families Odobenidae, Otariidae, and Phocidae. There are 33 extant species of pinnipeds, and more than 50 extinct species have been described from fossils. While seals were historically thought to have descended from two ancestral lines, molecular evidence supports them as a monophyletic lineage. Pinnipeds belong to the order Carnivora and their closest living relatives are bears and the superfamily of musteloids, having diverged about 50 million years ago.
Ailuridae is a family in the mammal order Carnivora. The family consists of the red panda and its extinct relatives.
Mammalia is a class of animal within the phylum Chordata. Mammal classification has been through several iterations since Carl Linnaeus initially defined the class. No classification system is universally accepted; McKenna & Bell (1997) and Wilson & Reader (2005) provide useful recent compendiums. Many earlier ideas from Linnaeus et al. have been completely abandoned by modern taxonomists, among these are the idea that bats are related to birds or that humans represent a group outside of other living things. Competing ideas about the relationships of mammal orders do persist and are currently in development. Most significantly in recent years, cladistic thinking has led to an effort to ensure that all taxonomic designations represent monophyletic groups. The field has also seen a recent surge in interest and modification due to the results of molecular phylogenetics.
Polecat is a common name for mammals in the order Carnivora and subfamilies Galictinae and Mustelinae. Polecats do not form a single taxonomic rank ; the name is applied to several species with broad similarities to European polecats, the only polecat species native to the British Isles.
Potamotherium an extinct genus of caniform carnivoran from the Miocene epoch of France and Germany. It has been previously assigned to the mustelid family, but recent work suggests that it represents a primitive relative of pinnipeds.
Enaliarctos is an extinct genus of pinniped, and may represent the ancestor to all pinnipeds. Prior to the discovery of Puijila, the five species in the genus Enaliarctos represented the oldest known pinniped fossils, having been recovered from late Oligocene and early Miocene strata of California and Oregon.
Desmatophoca is an extinct genus of early pinniped that lived during the Miocene, and is named from the Greek "phoca", meaning seal. A taxon of the family Desmatophocidae, it shares some morphological similarities with modern true seals. Two species are recognized: Desmatophoca oregonensis and Desmatophoca brachycephala. Little information exists regarding Desmatophoca, due to the small number of fossil samples obtained and identified.
Carnivoramorpha are a clade of mammals that includes the modern order Carnivora.
Feliformia is a suborder within the order Carnivora consisting of "cat-like" carnivorans, including cats, hyenas, mongooses, viverrids, and related taxa. Feliformia stands in contrast to the other suborder of Carnivora, Caniformia.
Stink badgers (Mydaus) are a genus of the skunk family of carnivorans, the Mephitidae. They resemble the better-known members of the family Mustelidae also termed 'badgers'. There are only two extant species – the Palawan stink badger or pantot, and the Sunda stink badger or teledu. They live only on the western islands of the Greater Sunda Islands: Sumatra, Java, Borneo in Indonesia and on the Philippine island of Palawan; as well as many other smaller islands in the region.
Musteloidea is a superfamily of carnivoran mammals united by shared characters of the skull and teeth. Musteloids share a common ancestor with the pinnipeds, the group which includes seals.
Phocinae is a subfamily of Phocidae whose distribution is found in the seas surrounding the Holarctic, with the Baikal seal being the world's only freshwater species of pinniped. What distinguishes them from other phocid seals is the presence of well-developed claws on their front and back flippers. The Phocinae is divided into three extant tribes: Erignathini, Cystophorini, and Phocini. Members of both Erignathini and Cystophorini have 34 chromosomes, while species in the tribe Phocini have 32 chromosomes.
Arctoidea is an infraorder of mostly carnivorous mammals which include the extinct Hemicyonidae (dog-bears), and the extant Musteloidea, Pinnipedia, and Ursidae (bears), found in all continents from the Eocene,, to the present. Arctoids are caniforms, along with dogs (canids) and extinct bear dogs (Amphicyonidae). The earliest caniforms were superficially similar to martens, which are tree-dwelling mustelids. Together with feliforms, caniforms comprise the order Carnivora.
Amphicynodontinae is a probable clade of extinct arctoids. While some researchers consider this group to be an extinct subfamily of bears, a variety of morphological evidence links amphicynodontines with pinnipeds, as the group were semi-aquatic otter-like mammals. In addition to the support of the pinniped–amphicynodontine clade, other morphological and some molecular analyses support bears being the closest living relatives to pinnipeds. According to McKenna and Bell (1997) Amphicynodontinae are classified as stem-pinnipeds in the superfamily Phocoidea. Fossils of these mammals have been found in Europe, North America and Asia. Amphicynodontines should not be confused with Amphicyonids (bear-dogs), a separate family of Carnivora which is a sister clade to arctoids within the caniforms, but which may be listed as a clade of extinct arctoids in older publications.
Pinnipedimorpha is a stem-clade of arctoid carnivorans that is defined to include the last common ancestor of Phoca and Enaliarctos, and all of their descendants of that ancestral taxon. Scientists still debate on which lineage of arctoid carnivorans are the closest relatives to the pinnipedimorphs, being either more closely related to bears or to musteloids.