What's most important about these animals is that they're extremely "basal," or undeveloped, compared to other "feliform" mammals like cats, hyenas and mongooses, clearly branching off millions of years ago from a low point of the carnivore family tree. Unusually for a supposed carnivore, at least one viverrid species the palm civet pursues a mostly vegetarian diet, while most other civets and genets are omnivorous.
The carnivore family Odobenidae comprises exactly one species, Odobenus rosmarus , better known as the walrus. There are, however, three Odobenus subspecies: the Atlantic walrus, O. Closely related to both earless and eared seals, walruses can weigh up to two tons, and are equipped with huge tusks surrounded by bushy whiskers; their favorite foods are bivalve mollusks, though they have also been known to eat shrimp, crabs, sea cucumbers, and even their fellow seals.
The panda no one ever talks about, the red panda Ailurus fulgens is an uncannily raccoon-like mammal of southwestern China and the eastern Himalayan Mountains, complete with a bushy, striped tail and prominent markings along its eyes and snout. Unusually for a member of the carnivore family, this tree-dwelling mammal mostly eats bamboo but has been known to supplement its diet with eggs, birds, and various insects. There are believed to be less than 10, red pandas in the world today, and even though it is a protected species, its numbers continue to dwindle.
In case you've never been to Indonesia or the Bay of Bengal, linsangs are slender, foot-long, weasel-like creatures with distinctive markings on their coats: head-to-tail bands with tabby-like tail rigs on the banded linsang Prionodon linsang , and leopard-like spots on the spotted linsang Prionodon pardicolor.
Both of these linsang species live exclusively in southeast Asia; analysis of their DNA has pegged them as a "sister group" to the Felidae that diverged from the main evolutionary trunk millions of years ago. Probably the most obscure animals on this page, fossas, falanoucs, and a half-dozen species confusingly referred to as "mongooses" comprise the carnivore family Eupleridae, which is restricted to the Indian Ocean island of Madagascar.
Genetic analysis has shown that the 10 extant species of euplerids, sometimes known as Malagasy mongooses, derive from a true mongoose ancestor that accidentally rafted over to this island during the middle Cenozoic Era , about 20 million years ago. Like much of the wildlife of Madagascar, many euplerids are severely endangered by the encroachment of human civilization.
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Select personalised ads. Apply market research to generate audience insights. Measure content performance. They all have furry or hairy coats that usually thicken in the winter. Many are nocturnal. The teeth are well developed and include molars and sharp canines ideal for the shredding of meat. The sense of smell is very acute, as is the sense of sight in most species.
Pack hunting is mostly consistent with the canines, felines, and hyenas. All carnivores have strong claws and chest muscles and prominent canines. The 12 families of carnivore are: Canidae dogs, jackals, fox, wolves Ursidae bears, panda Procyonidae raccoons, lesser panda Mustelidae otters, weasels, badgers Mephitidae skunks-previously part of Mustelidae Viverridae civets, genets Herpestidae mongooses-often considered part of Viverridae Hyaenidae hyenas, aardwolf Felidae cats, lion, tiger Odobenidae walrus Phocidae true, earless, or hair seals Otariidae eared seals, sea lions Carnivores are naturally distributed throughout the world, except for Australia, New Guinea, New Zealand, Antarctica, and many oceanic islands.
One species, Canis familiaris, apparently was introduced into Australia by human agency in prehistoric time and subsequently established wild populations on that continent. Two living superfamilies of carnivores are usually recognised: Arctoidea or Canoidea , with the families Canidae, Ursidae, Procyonidae, and Mustelidae; and the Aeluroidea or Feloidea , with the families Viverridae, Hyaenidae, and Felidae.
The Pinnipedia with families Odobenidae, Phocidae, and Otariidae are often regarded as a full separate order. The smallest living carnivore is the least weasel Mustela nivalis , which has a weight of grams. The largest is the Kodiak subspecies of grizzly bear reaching a weight of kg. Members of the mammalian order Carnivora are the descendants of a successful late Paleocene radiation of mammals whose primitive food habits were carnivorous.
The name "Carnivora" is sometimes taken to mean that members of this group are all carnivorous or that all carnivorous mammals are members of this group.
This is not so. Members of Carnivora have diverse food habits, although many are primarily carnivorous, and carnivory is widely distributed in mammals, being found in many other orders including bats , marsupial mammals , primates , and dolphins and whales. We recognize 13 extant families and around species of Carnivora.
Stains, ; Vaughan, et al. Carnivores are distributed across the world, on all major land masses except possibly Australia, where the only terrestrial member of Carnivora, dingos Canis lupus dingo , may have been brought by man and in all oceans. Carnivores occupy just about every type of terrestrial habitat, and many aquatic habitats as well, from the tropics to the poles.
They live in forests, deserts, mountains, grasslands, scrublands, tundra, and on open ice. Aquatic and semi-aquatic species live in freshwater rivers, lakes, and marshes, in marine coastal areas, and in the open ocean. Most members of the order Carnivora can be recognized by their enlarged fourth upper premolar and first lower molar , which together form an efficient shear for cutting meat and tendon. These teeth are referred to as the carnassial pair.
The exceptions are a few forms, such as bears , raccoons , and seals , in which these teeth are secondarily modified. The outer 3rd incisor is often relatively large and canine-like.
The canines are large and conical. All teeth are rooted and diphyodont. The skulls of carnivorans are varied in form. Most have a well-defined, transverse glenoid fossa , and the dominant motion of the jaw is in the dorsal-ventral direction. The primary muscle powering the jaw is the temporal, and sagittal crest associated with the temporal is commonly a conspicuous part of the surface of the skull.
Carnivores also have a strong zygomatic arch and a relatively large braincase. The auditory bullae and the turbinals also tend to be large and complex. Carnivores are fairly intelligent animals and most have relatively large brains. All members of Carnivora have simple stomachs.
Pinnipeds are large, perhaps because water conducts heat well and large animals have a low surface area to body mass ratio, which minimizes heat loss due to conduction. Their bodies are insulated by a thick layer of fat called blubber. In all species, the external ears are small or absent, the external genitalia and nipples are hidden in slits or depressions in the body, and the tail is very small. The forelimbs and hindlimbs are transformed into paddles.
In both, the proximal limb elements humerus and femur remain within the body, and other aspects of the limbs, limb girdles, and spine are highly specialized for swimming. Most species have a relatively short rostrum, and the orbits are large.
The cheek teeth are usually homodont no differentiation along the toothrow , and the teeth are usually shaped like simple cones. Carnivores tend to be medium-sized animals; too small and they couldn't find enough within their capacity to kill; too large and they wouldn't be able to satisfy their appetites.
However, as a group, carnivores span a wide range of body sizes. Least weasels Mustela nivalis , the smallest carnivores, can weigh as little as 35 grams, and male southern elephant seals Mirounga leonina , the largest carnivores, can weigh more than 3, kg. Many carnivore species are sexually dimorphic in size. Usually males are larger than females as with fishers , lions , and wolves but in a few species females are larger than males as with spotted hyenas. Additionally, males of some species have ornamentation that females lack as is the case with the inflatable probosci of male elephant seals.
Many carnivores have thick, luxurious coats, though some, like walruses , have coats that are quite sparse. Their fur comes in various colors, including black, white, orange, yellow, red, and almost every imaginable shade of gray and brown. In addition, many carnivores are striped, spotted, blotched, banded, or otherwise boldly patterned. Some species, such as gray wolves , are polymorphic for coat color. Domesticated cats and dogs exhibit thousands of combinations of coat colors and body shapes as a result of selective breeding by humans.
Carnivores have polygynous, polygynandrous, and monogamous mating systems. Southern elephant seals Mirounga leonina demonstrate extreme polygyny, wherein males fight for exclusive access to harems of females. Gray wolves Canis lupus , on the other hand, are monogamous cooperative breeders; the dominant male and female of each pack breed and all members of the pack help raise their offspring. Solitary carnivores, such as bears , mustelids , and cats , are often polygynandrous, with males and females each having multiple partners during the breeding season.
Ewer, ; King, ; Moehlman, ; Reeves, et al. Carnivores breed either aseasonally or seasonally; those in cold climates usually mate in winter and spring and give birth to their young during spring and summer. Females may be polyestrus or monoestrus; in some species, ovulation is induced by the act of mating.
Carnivores may have two or three litters per year as with least weasels , but most carnivore females have just one litter every one to two years. Delayed implantation, wherein the blastocyst lies quiescent for several months before implanting in the uterine lining, is common in some carnivore families such as mustelids.
After implantation, gestation periods range from five weeks in least weasels to 15 months in walruses. Typical true gestation periods last two to four months. Litter sizes range from 1 to 16, and are commonly 3 to 5.
Females nurse their young for up to two years, and the young take up to seven years to reach sexual maturity. Ewer, ; Mead, ; Reeves, et al. Female carnivores nurture their young inside their bodies for up to 15 months and provide their young with milk after birth. The length of nursing varies considerably among carnivores. Some phocids only nurse their young for a couple of weeks, whereas walruses nurse their young for up to two years. The duration of lactation in terrestrial carnivores falls between these two extremes.
Carnivore young range from highly precocial, harbor seal Phoca vitulina pups are able to swim a few minutes after birth, to altricial, as in bears. Female carnivores usually bear the sole responsiblity for nurturing and protecting their offspring, but male parental care is not uncommon, especially among canids. Carnivores that live in groups and breed communally may all share in the task of raising each others' offspring.
In some social species, like spotted hyenas Crocuta crocuta , the mother's position in the dominance hierarchy determines the position of her offspring. The young of spotted hyenas , wolverines , sea otters , bears , and large felids stay with their mothers for up to two years even though they are weaned well before this time; they depend on their mothers for food until they become proficient at hunting for themselves.
In carnivores that form close-knit social groups, bonds between mother and offspring may extend well beyond the period of offspring dependency. Ewer, ; Frank, ; Gittleman, ; Moehlman, ; Reeves, et al. Carnivores are relatively long-lived mammals, with most species living at least a decade. The main exceptions are small weasels Mustela , which live up to six years in captivity but usually do not make it past one year in the wild.
In general, pinniped carnivores live longer than fissiped carnivores, with several species walruses , gray seals , ringed seals , Caspian seals , and Baikal seals reported to live 40 or more years in the wild. Carey and Judge, ; King, Carnivora includes terrestrial, aquatic, and semi-aquatic species. Aquatic species pinnipeds are excellent swimmers, more at home in the water than on land.
These animals are capable of diving to extreme depths m in the case of Weddell seals and remaining under water for astonishing periods over an hour, although most dives are much shorter.
Some carnivores, such as procyonids , are skilled climbers and spend much of their time in trees. Many terrestrial carnivores are excellent runners. A few are good long-distance runners , but more commonly, carnivorans are rapid sprinters that use stealth to approach their prey, then overcome it with a short, violent rush. A few, like bears and raccoons , seem relatively slow or clumsy, but even these species are capable of remarkable bursts of speed. Even those specialized for long-distance running don't have the highly modified and relatively inflexible skeletons and movement patterns of cursorial herbivores like artiodactyls ; this is probably related to the often unpredictable demands that catching and killing large prey place on their skeletons.
Gittleman, ; Sandell, ; Stains, ; Vaughan, et al. Carnivores exhibit varying degrees of sociality, ranging from solitary bears , for example to colonial California sea lions , for example. Some carnivore species are difficult to place in a single category, as their degree of sociality varies over their geographic range or even among sex and age classes within a population. For example, red foxes Vulpes vulpes breed cooperatively in some regions and are largely solitary in others, and female coatis Nasua nasua live in close groups, whereas male coatis are solitary.
For social carnivores, group living often entails the formation of strictly-enforced dominance hierarchies. Social bonds among group members can be very strong, with individuals showing affection for one another and keeping each other out of trouble.
Some carnivore species undergo seasonal long-distance migrations in concert with the migrations of their prey. Others stay within one home range year round.
Home ranges tend to be large, and often vigorously defended, as each carnivore's home range must encompass the home ranges of many prey animals. Carnivora includes both diurnal and nocturnal species. When resting, many carnivorans den in tree hollows, burrows, or caves.
A few species, such as those in the family Ursidae , undergo long periods of torpor through the winter. Most carnivorans have acute senses. Vision and hearing are excellent in many, often far surpassing the capabilities of humans. Domestic cats and other carnivores that hunt small rodents can hear ultrasounds emitted by their prey.
Most carnivorans come equipped with tactile hairs vibrissae on the face and legs, which they use to feel their way through narrow, dark surroundings. The sense of smell is often remarkable. Carnivorans make extensive use of chemical signals excreted in urine and feces and produced by glands in the skin and anal region.
They use these chemical signals for scent-marking territories and for conveying information about identity, social status, and reproductive status.
Carnivorans also communicate acoustically with a variety of yips, howls, barks, growls, roars, and purrs. These sounds have various functions, including strengthing social bonds, advertising for mates, defending territories, and communicating alarm, distress, and contentment.
Social carnivores such as lions sometimes erupt into choruses of loud roars as a means of calling one another to assemble. Visual signals, mainly in the form of body posturing, are also used by carnivorans to communicate, and tactile signals, as when a wolf licks and bites the muzzle of a dominant individual to show submission, are used as well. Animal matter makes up a substantial portion of the diet of most carnivorans.
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