Caniformia

Caniformia, or Canoidea (literally 'dog-like'), is a suborder within the order Carnivora. They typically possess a long snout and nonretractile claws (in contrast to the cat-like carnivorans, the Feliformia). 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. This contrasts with the feliforms, 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. 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.