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1 Your web browser (Safari 7) is out of date. For more security, comfort and Encyclopedic the best experience Entry on this site: Update your browser Ignore carnivore secondary consumer For the complete encyclopedic entry with media resources, visit: A carnivore is an organism that mostly eats meat, or the flesh of animals. Sometimes carnivores are called predators. Organisms that carnivores hunt are called prey. Carnivores are a major part of the food web, a description of which organisms eat which other organisms in the wild. Organisms in the food web are grouped into trophic, or nutritional, levels. There are three trophic levels. Autotrophs, organisms that produce their own food, are the first trophic level. These include plants and algae. Herbivores, organisms that eat plants and other autotrophs, are the second trophic level. Carnivores are the third trophic level. Omnivores, creatures that consume a wide variety of organisms from plants to animals to fungi, are also the third trophic level. Autotrophs are called producers, because they produce their own food. Herbivores, carnivores, and omnivores are consumers. Herbivores are primary consumers. Carnivores and omnivores are secondary consumers. Many carnivores eat herbivores. Some eat omnivores, and some eat other carnivores. Carnivores that consume other carnivores are called tertiary consumers. Killer whales, or orcas, are a classic example of tertiary consumers. Killer whales hunt seals and sea lions. Seals and sea lions are carnivores that consume fish, squid, and octopuses. Some carnivores, called obligate carnivores, depend only on meat for survival. Their bodies cannot digest plants properly. Plants do not provide enough nutrients for obligate carnivores. All cats, from small house cats to huge tigers, are obligate 1 of 8

2 carnivores. Most carnivores are not obligate carnivores. A hypercarnivore is an organism that depends on animals for at least 70 percent of its diet. Plants, fungi, and other nutrients make up the rest of their food. All obligate carnivores, including cats, are hypercarnivores. Sea stars, which prey mostly on clams and oysters, are also hypercarnivores. Mesocarnivores depend on animal meat for at least 50 percent of their diet. Foxes are mesocarnivores. They also eat fruits, vegetables, and fungi. Hypocarnivores depend on animal meat for less than 30 percent of their diet. Most species of bears are hypocarnivores. They eat meat, fish, berries, nuts, and even the roots and bulbs of plants. Hypocarnivores such as bears are also considered omnivores. The planet s largest animal is a carnivore. The blue whale can reach 30 meters (100 feet) long and weigh as much as 180 metric tons (200 tons). It feeds by taking huge gulps of water and then filtering out tiny shrimp-like creatures called krill. The blue whale can eat about 3.6 metric tons (4 tons) of krill every day that s about 40 million of the little creatures. The largest land carnivore is the polar bear, which feeds mainly on seals. Hunting Carnivores have biological adaptations that help them hunt. Carnivorous mammals such as wolves have strong jaws and long, sharp teeth that help them grab and rip apart their prey. Plant-eaters, on the other hand, usually have big molars that help them grind up leaves and grasses. Lions, cougars, and other cats have sharp claws that they use to hunt. Birds such as hawks and owls also hunt with their claws, called talons. Many carnivorous birds, called raptors, have curved beaks that they use to tear apart their prey. Many carnivores grab their prey in their mouths. Great blue herons wade slowly through shallow water and then suddenly snatch a fish, crab, or other creature 2 of 8

3 from the water. Toads grab mice in their mouths. Sperm whales dive deep into the ocean where they bite hold of squid. Spiders capture their prey usually insects by trapping them in a sticky web. Other carnivores attack their prey with a bite or a sting that injects toxic venom into the victim. The venom either paralyzes or kills the prey. Snakes such as king cobras have hollow fangs that act like needles to inject venom. Cobras mostly prey on other snakes. Jellyfish have stingers on their tentacles, which paralyze fish swimming nearby. Most carnivores are animals, but plants and fungi can be carnivores also. The Venus flytrap is a plant that catches insects in its leaves. When an insect brushes against the sensitive hairs on the leaf, the leaf folds in two and snaps shut. The insect is trapped inside. Other carnivorous plants, such as the sundew, produce a sticky material that catches insects. Fungi are a group of organisms that include mushrooms, molds, and mildew. Some fungi trap and consume tiny organisms. Most carnivorous fungi prey on microscopic worms called nematodes, which they trap with suffocating rings. Diets Certain types of carnivores have specific diets. Some, such as sea lions, eat mainly fish. They are called piscivores (piscis is the Latin word for fish). Others, such as lizards, eat mainly insects. They are called insectivores. Many bats are also insectivores. One little brown bat can eat a thousand mosquitoes in an hour. Some insects are themselves insectivores. These include ladybugs, dragonflies, and praying mantises. Carnivores that have been known to attack and eat human beings are known as man-eaters. Some species of sharks, alligators, and bears are called man-eaters. However, no carnivore specifically hunts human beings or relies on them as a regular food source. Cannibals are carnivores that eat the meat of members of their own species. Many animals practice cannibalism. For some species, cannibalism is a way of eliminating 3 of 8

4 competitors for food, mates, or other resources. Chimpanzees and bears, for example, will hunt and consume the young of family members, sometimes their own offspring. Praying mantis females will kill and eat the bodies of their mates. Many carnivores are scavengers, creatures that eat the meat of dead animals, or carrion. Unlike other types of carnivores, scavengers usually do not hunt the animals they eat. Some, such as vultures, consume animals that have died from natural causes. Others, such as hyenas, will snatch meat hunted by other carnivores. Many insects, such as flies and beetles, are scavengers. Some carnivores, including sea lions, feed often. Others, such as king cobras, can go months between meals. Carnivores in the Food Chain For a healthy ecosystem, it is important that the populations of autotrophs, herbivores, and carnivores be in balance. Energy from nutrients is lost at each trophic level. It takes many autotrophs to support a fewer number of herbivores. In turn, a single carnivore may have a home range of dozens or even hundreds of miles. A Siberian tiger, for instance, may patrol a range of 1,000 square kilometers (386 square miles). In some places, the disappearance of large carnivores has led to an overpopulation of herbivores, disrupting the ecosystem. Wolves and cougars are traditional predators of white-tailed deer, for instance. But hunting and development have eliminated these predators from the northeastern United States. Without natural predators, the population of white-tailed deer has skyrocketed. In some areas, there are so many deer that they cannot find enough food. They frequently stray into towns and suburbs in search of food. Carnivores depend on herbivores and other animals to survive. Zebras and gazelles once traveled in great herds over the plains of Africa. But these herds have shrunk and are now mostly confined to parks and wildlife reserves. As the numbers of these herbivores decline, carnivores such as African wild dogs, which 4 of 8

5 prey on them, also decline. Scientists estimate that only 3,000 to 5,500 African wild dogs remain in the wild. Vocabulary Term Part of Speech Definition algae plural (singular: alga) diverse group of aquatic organisms, the largest of which are seaweeds. organism that can produce its own food and nutrients autotroph from chemicals in the atmosphere, usually through photosynthesis or chemosynthesis. avivore organism that mostly eats birds. biological physical change in an organism that results over time in adaptation reaction to its environment. blue whale species of marine mammal that is the largest animal to have ever lived. cannibal organism that eats the meat of members of its own species. carnivore organism that eats meat. carrion flesh of a dead animal. organism on the food chain that depends on autotrophs consumer (producers) or other consumers for food, nutrition, and energy. development growth, or changing from one condition to another. diet foods eaten by a specific group of people or other organisms. digest verb to convert food into nutrients that can be absorbed. ecosystem community and interactions of living and nonliving things in an area. eliminate verb to remove. fang long, sharp, protruding tooth. In many animals, fangs are hollow and used to inject venom. to remove particles from a substance by passing the filter verb substance through a screen or other material that catches larger particles and lets the rest of the substance pass through. 5 of 8

6 food chain food web frequent group of organisms linked in order of the food they eat, from producers to consumers, and from prey, predators, scavengers, and decomposers. all related food chains in an ecosystem. Also called a food cycle. adjectiveoften. fruit edible part of a plant that grows from a flower. fungi plural (singular: fungus) organisms that survive by decomposing and absorbing nutrients in organic material such as soil or dead organisms. herbivore organism that eats mainly plants. home range area where an animal lives. hypercarnivore hypocarnivore organism that depends on meat for more than 70 percent of its diet. organism that depends on meat for less than 30 percent of its diet. insectivore organism that mostly eats insects. killer whale carnivorous whale, actually the world's largest species of dolphin. Also called an orca. krill small marine crustacean, similar to shrimp. mammal man-eater animal with hair that gives birth to live offspring. Female mammals produce milk to feed their offspring. organism that has been known to hunt and kill human beings. meat animal flesh eaten as food. mesocarnivore microscopic mildew Term Part of Speech organism that depends on meat for at least 50 percent of its diet. adjective very small. Definition type of fungi that usually forms a thin, powdery layer over plants or other organic material. molar large, flat tooth used for chewing and grinding. mold type of fungi that forms on the surface of materials. nematode microscopic, worm-like animal. 6 of 8

7 Term Part of Speech Definition nutrient substance an organism needs for energy, growth, and life. nutrition process by which living organisms obtain food or nutrients, and use it for growth. obligate organism that depends entirely on meat for food, carnivore nutrition, and survival. offspring the children of a person or animal. omnivore organism that eats a variety of organisms, including plants, animals, and fungi. organism living or once-living thing. overpopulation situation where the amount of organisms in an area is too large for the ecosystem to support. ovivore organism that mostly eats eggs. paralyze verb to prevent movement. piscivore organism that mostly eats fish. plant organism that produces its own food through photosynthesis and whose cells have walls. polar bear large mammal native to the Arctic. predator animal that hunts other animals for food. prey animal that is hunted and eaten by other animals. primary consumer organism that eats plants or other autotrophs. producer organism on the food chain that can produce its own energy and nutrients. Also called an autotroph. raptor bird of prey, or carnivorous bird. scavenger organism that eats dead or rotting biomass, such as animal flesh or plant material. sea star marine animal (echinoderm) with many arms radiating from its body. Also called a starfish. secondary consumer organism that eats meat. skyrocket verb to increase rapidly. species group of similar organisms that can reproduce with each other. 7 of 8

8 Term Part of Speech Definition spongivore organism that mostly eats sea sponges. sundew carnivorous plant with sticky hairs that trap insects. talon claw of a bird, especially a bird of prey or raptor. tentacle a long, narrow, flexible body part extending from the bodies of some animals. tertiary consumer carnivore that mostly eats other carnivores. toxic adjectivepoisonous. trophic level one of three positions on the food chain: autotrophs (first), herbivores (second), and carnivores and omnivores (third). vegetable plant that is grown or harvested for food. venom poison fluid made in the bodies of some organisms and secreted for hunting or protection. Venus flytrap carnivorous plant that traps and consumes mostly insects. vermivore organism that mostly eats worms. area set aside and protected by the government or other wildlife organization to maintain wildlife habitat. Also called a reserve nature preserve. Images New York State Museum: Mammals Revealed Carnivore Scat Websites National Geographic Ocean: Marine Food Chain National Geographic Society. All rights reserved. 8 of 8