Caniformia is a suborder within the order Carnivora consisting of "dog-like" carnivorans. They include Canidae (Wolf, , etc.), , , and Mustelidae. The Pinnipedia (pinniped, and ) also belong to this group. The center of diversification for the Caniformia is North America and northern Eurasia. Caniformia stands in contrast to the other suborder of Carnivora, the Feliformia ("cat-like" carnivorans), the center of diversification of which was in Africa and southern Asia.
Description
Extant families
Family Canidae (dogs and other Canidae) includes Gray wolf, , Coyote, and , 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 ( in males) to the small sun bear ( in males) 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 Myrmecophagy, 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 genus: Mephitis (hooded and striped skunks, two species), Spilogale (spotted skunks, four species), Mydaus (stink badgers, two species) and Conepatus (, 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 .
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 Canidae that adapted to more omnivorous diets.
Pinnipedia (seals, sea lions, and walruses clade) is a widely distributed and diverse group of semiaquatic 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 Cladogenesis from other caniforms 50 million years ago (Mya) during the Eocene.
The clade is currently divided into three families:
Debate continues on the origin of pinnipeds. Recent molecular evidence suggests pinnipeds evolved from a bear-like ancestor about 23 Mya during the Chattian 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 .
Evolution
Classification
Phylogeny
External links
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