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Carnivore
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A carnivore , meaning 'meat eater' (Latin carne meaning 'flesh' and vorare meaning 'to devour'), is any animal with a diet consisting mainly of meat, whether it comes from animals living (predation) or dead (scavenging).
In a more general sense, an animal may be considered a carnivore if it prefers feeding on animal matter over plant matter. Animals that must eat meat in order to thrive are referred to as obligate carnivores, whereas animals that exclusively feed on animal tissue are known as hypercarnivores.
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Encyclopedia
A carnivore , meaning 'meat eater' (Latin carne meaning 'flesh' and vorare meaning 'to devour'), is any animal with a diet consisting mainly of meat, whether it comes from animals living (predation) or dead (scavenging).
In a more general sense, an animal may be considered a carnivore if it prefers feeding on animal matter over plant matter. Animals that must eat meat in order to thrive are referred to as obligate carnivores, whereas animals that exclusively feed on animal tissue are known as hypercarnivores. An apex predator is a carnivore that sits at the top of the foodchain.
Plants that capture and digest insects are called carnivorous plants. Similarly fungi that capture microscopic animals are often called carnivorous fungi.
Classification
Carnivores are classified by their dietary behaviour. However, because the specific definition of what exactly meat is can be flexible, so too can the definition of carnivore. In the strictest sense, meat may refer to the flesh of mammalian species, but in a broader sense the term might be used to refer to any animal tissue considered food.
Carnivores that eat insects and similar invertebrates primarily or exclusively are called insectivores, while those that eat fish primarily or exclusively are called piscivores. Carnivory that entails the consumption of members of an organism's own species is referred to as cannibalism. This includes sexual cannibalism and cannibalistic infanticide.
The word "carnivore" sometimes refers to the mammalian Order Carnivora, but this is somewhat misleading. Although many Carnivora fit the definition of being exclusively meat eaters, not all do. For example, bears are members of Carnivora, yet are not carnivores in the dietary sense, and pandas are almost exclusively herbivorous. In addition, some full-time (dolphins, shrews) and part-time (humans, pigs) meat-eating mammalian species, as well as all carnivorous non-mammals, are not members of Carnivora.
Outside of the animal kingdom, there are several genera containing carnivorous plants and several phyla containing carnivorous fungi. The former are predominantly insectivores, while the latter prey mostly on microscopic invertebrates such as nematodes, amoeba and springtails.
Obligate carnivores
An obligate or true carnivore is an animal that must eat meat in order to survive. They may consume other products presented to them, especially animal products like eggs and bone marrow or sweet sugary substances like honey and syrup, but, as these items are not essential, they do not consume these on a regular basis. True carnivores lack the physiology required for the efficient digestion of vegetable matter, and, in fact, some carnivorous mammals eat vegetation specifically as an emetic. The domestic cat is a prime example of an obligate carnivore, as are all of the other felids.
A hypercarnivore presents specialized dentition for a meat-only diet.
Characteristics of carnivores
Characteristics commonly 'associated' with carnivores include organs for capturing and disarticulating prey (teeth and claws serve these functions in many vertebrates) and status as a predator. In truth, these assumptions may be misleading, as some carnivores do not hunt and are scavengers (though most hunting carnivores will scavenge when the opportunity exists). Thus they do not have the characteristics associated with hunting carnivores. Carnivores have comparatively short digestive systems as they are not required to break down tough cellulose found in plants.
Plant material
In most cases, some plant material is essential for adequate nutrition, particularly with regard to minerals, vitamins and fiber. Most wild carnivores consume this in the digestive system of their prey. Many carnivores also eat herbivore dung, presumably to obtain essential nutrients that they could not otherwise obtain, since their dentition and digestive system do not permit efficient processing of vegetable matter.
Prehistoric carnivores
Prehistoric mammals of the crown-clade Carnivoramorpha (Carnivora and Miacoidea without Creodonta), along with the early Order Creodonta, and some mammals of the even early Order Cimolesta, were true carnivores. The earliest carnivorous mammal is considered to be the Cimolestes that existed during the Late Cretaceous and Tertiary Periods in North America about 65 million years ago. Most species of Cimolestes were mouse to rat-sized, but the Late Cretaceous Cimolestes magnus reached the size of a marmot, making it one of the largest Mesozoic mammals known (20-60g). The cheek teeth combined the functions of piercing, shearing and grinding, and the molars of Palaeoryctes had extremely high and acute cusps that had little function other than piercing. The dentition of Cimolestes foreshadows the same cutting structures seen in all later carnivores. While the earlier smaller species were insectivores, the later marmot-sized Cimolestes magnus probably took larger prey and were definitely a carnivore to some degree. The cheek teeth of Hyracolestes ermineus (an ermine-like shrew - 40g) and Sarcodon pygmaeus ("pygmy flesh tooth" - 75g), were common in the Latest Paleocene of Mongolia and China and occupied the small predator niche. The cheek teeth show the same characteristic notches that serve in today's carnivores to hold flesh in place to shear apart with cutting ridges.
The theropod dinosaurs such as Tyrannosaurus rex that existed during the late Cretaceous were "obligate carnivores".
List of extant carnivores
Mammals
- All feliforms, such as domestic cats, big cats, hyenas, mongooses, civets
- Most caniforms, such as the dogs, wolves, foxes, ferrets, bears, seals and walruses
- All cetaceans, such as dolphins, whales and porpoises
- All bats (except fruitbats)
- The carnivorous marsupials, such as the tasmanian devil
Birds
- All birds of prey, such as hawks, eagles, falcons and owls
- All vultures, both old world and new
- Some waterfowl, such as gulls, penguins, pelicans, storks, and herons
Reptiles
- All crocodilians, such as alligators, crocodiles, gharials and caimans
- All snakes, such as cobras, vipers, pythons and boas
- Some lizards, such as most skinks and all monitor lizards
- Some turtles, including the snapping turtle and most sea turtles
Fish and amphibians
- Most anurans, such as frogs and toads
- All sharks, such as tiger, great white, nurse and reef sharks
- Many bony fish, such as tuna, marlin, salmon, and bass
Invertebrates
- Some molluscs, such as octopuses and squid, and some gastropods
- Most arachnids, such as spiders and scorpions
- Many insects, such as mantises, dragonflies and most wasps
- All jellyfish and sea stars
See also
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