The Complete List Of Animals

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Caterpillars are the larvae, or young, of butterflies and moths. The word comes from the Latin catta pilosa, meaning “hairy cat.” Although it is easy to recognize the hairy variety, many caterpillars with bare skins are often mistaken for worms, such as the cabbageworm and armyworm.

Physical features

Body parts
The head of a caterpillar is followed by 12 or 13 segments. Like all insects, caterpillars have three pairs of permanent legs, one pair on each of the first three segments directly behind the head. These legs are usually hard and jointed. At their tips are tiny claws, but in some caterpillars these are not developed. The caterpillar also has two to five pairs of soft, thick prolegs that support the rest of its long body. These disappear when it changes into a moth or butterfly. A caterpillar has six tiny bead-like eyes on each side of the head, just above the strong upper jaws. It breathes through nine small openings on each side of its body. These are called tracheae. It also has short antennae.

Size
Caterpillars vary in size from less than an inch to a few inches. For example, the hawk moth caterpillar, one of the largest, may grow to be 4 inches (10 centimeters) long. The clothes moth caterpillar, one of the smallest, is almost never bigger than 14 inch (0.6 centimeter).

Defenses
Caterpillars are the prey of many birds and insects. To avoid attacks, they have natural protections. Some caterpillars are colored to blend into their surroundings. Others have showy dots or stripes on their bodies that make them look fierce or very large. A few give off unpleasant smells, and a small number grow poisonous hair.

Molting
A caterpillar hatches from the egg laid by a female butterfly or moth. It grows quickly and soon becomes too large for its skin. The skin splits and the caterpillar wiggles out. This process, called molting, occurs four or five times before a caterpillar turns into a butterfly or moth. Some caterpillars eat up their old skins.

Metamorphosis

The change that caterpillars undergo to turn into butterflies or moths is called metamorphosis. Some caterpillars may take only a few days to turn into butterflies or moths. Most, however, stay as caterpillars throughout the warm season. A small number may live as long as four years in the caterpillar form before they change.

Cocoon
The first step for many caterpillars is to build cocoons or shells. They spin them with threads of sticky fluid that flow from an opening in their lower lip. The fluid hardens in the air to form the covering.

Some caterpillars form bags of silk that enclose them completely. Others roll up a leaf and fasten the edges with the silk. Many hairy caterpillars pad their cocoons with their own hair. Some caterpillars do not build cocoons. Many of the moth caterpillars take shelter simply by burrowing in the ground or under a stone or fallen leaf. The butterfly caterpillars may hang from leaves or twigs by their tails. They can also spin a button of silk on a twig or leaf and dangle from it by a silk strap.

Pupa
Whether protected by a cocoon or not, the caterpillar gradually becomes ready to shed its last skin. Then the caterpillar grows a tough flexible shell or case. When this happens, the caterpillar has become a pupa. The moth pupa is usually dull brown. The butterfly pupa is sometimes called a chrysalis. It is shiny and often has brilliant colors.

Adult
Important changes happen to the pupa in the shell. Wings and other organs grow to make the caterpillar a moth or butterfly. This change to the adult stage may take anywhere from a few days to several months. Finally, the new moth or butterfly emerges from the shell and begins its new life.

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A catfish looks something like a cat because it has one or more pairs of whiskerlike feelers by its mouth. These feelers, known as barbels, are sensory organs—they help the fish to taste and feel.

Where catfish live
There are about 2,500 species, or kinds, of catfish. They are found in the freshwater bodies of all of the major continents. A few live in temperate (mild) and tropical oceans. Bullheads and channel catfish are two types of catfish common to North America.

Physical features
Catfish range greatly in size. The largest is the Danube sheatfish, or wels. This catfish may be more than 15 feet (4.5 meters) long and weigh 660 pounds (300 kilograms). Some of the smaller catfish species are popular for aquariums because they barely measure 2 inches (5 centimeters) in length.

Catfish do not have scales. All catfish are either naked or have bony plates. Many catfish have poisonous spines on their back and sides for protection from enemies.

Behavior
Catfish tend to be most active at night. They are scavengers that feed on almost any kind of animal or vegetable matter.

A female catfish can lay thousands of eggs. Some kinds of catfish carry the eggs in their broad mouths to protect them. Some others build a nest for the eggs and guard them.

Catfish and humans
Many people eat catfish. While frying the fish is perhaps the most common way it is prepared, catfish can also be cooked in other ways. Many catfish are raised in controlled environments to keep the quality and supply of catfish high. Mississippi, Arkansas, Alabama, and Louisiana are leading producers of farm-raised catfish in the United States.

Catfish are also popular to catch. People fishing in rivers may try to land a channel catfish, which can weigh more than 50 pounds (23 kilograms). Kids dangling a simple stick and worm can catch smaller catfish.

The word cattle was once used to describe all animals raised by humans. Over time the word came to refer only to bovine farm animals that are raised for their meat, milk, or hide, as well as their close relatives, including the buffalo, bison, and yak. These animals are called bovine because they share certain features of the scientific family Bovidae. The term cattle is most often used specifically for the farm animals. Some scientists call these the true cattle.

Cattle are given different names depending on their age and ---. A male bovine, first called a bull calf, grows into a bull. The female is called a heifer calf when young and a cow in maturity. A mature male that has been operated on so that it cannot breed is known as a steer and later an ox.

Where cattle live
Cattle are found almost everywhere in the world. They are native to Europe, Asia, and Africa, but they were brought to North and South America and Australia and are now common there as well. In Asia there are both wild and domestic forms of true cattle. In the wild many cattle live in forested areas with open grassy areas nearby in which they can graze. Domestic cattle are raised by humans to be used for their milk, meat, or hide or to be used to perform heavy work. These are the animals that are most commonly thought of as cattle. In India the domestic cattle are considered holy by followers of Hinduism. It is considered a sin to kill a cow, and the animals are allowed to roam freely throughout the cities as well as the countryside.

Physical features
Depending on the breed, mature bulls weigh about 1,000–4,000 pounds (450–1,800 kilograms) and cows weigh about 800–2,400 pounds (360–1,000 kilograms). They come in a wide range of colors, including black, white, gray, yellow, brown, red, or a combination of these. They are often marked with spots and blotches. Almost all cattle have horns that are hollow.

Behavior
In the wild, cattle eat grasses and other vegetation. Cattle are ruminants, which means that they first swallow their food and then bring it up from the stomach to be chewed and swallowed again. This process is known as chewing the cud. It helps them digest difficult foods such as grasses. They do not have teeth in the front of their upper jaw. In order to eat, a bovine grabs rooted grass in its mouth. It pulls the grass free by a sideways movement of its head.

Domestic cattle are fed specific diets depending on whether they will be used as beef or dairy cattle. Beef cattle are generally heavier than dairy cattle and are fed special diets to make them fatter.

Life cycle
The life span of cattle in the wild is about 20 years. Cows give birth to one or two young about nine months after mating. At birth, a calf weighs about 80 pounds (36 kilograms). Beef calves are weaned, or taken off their mother's milk, at 6 to 7 months of age. At this time they weigh from 350 to 650 pounds (160 to 300 kilograms). Most fattened beef cattle are taken to market between 15 to 24 months of age, when they weigh between 1,000 and 1,400 pounds (450 and 630 kilograms).

Breeds
All modern European domestic cattle are thought to have descended from a form, known as the aurochs, that lived in Asia and Europe in ancient times. Beginning about 8,000 years ago people began to domesticate the animal. At first they used all cattle for all purposes. Eventually, however, they began to develop separate breeds that had unique features. Modern cattle in the United States and Europe can be categorized into two main varieties, dairy and beef, though some cattle continue to serve more than one purpose. Each of these categories has a number of breeds.

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Hereford bull
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Holstein-Friesian cow
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Brahman bull


The most popular dairy cattle in the United States include the Holstein-Friesian, Brown Swiss, Jersey, and Guernsey breeds. Of the cattle raised for beef, the Angus, Shorthorn (or Durham), Hereford, and Brahman are among the most common breeds. The Brahman was originally produced by mating the Indian cattle known as the zebu with certain domestic breeds. The Brahman is popular in the southern United States because it endures heat and resists disease and insect bites better than other breeds. The Brahman is characterized by a pronounced hump over the shoulder and neck, horns that usually curve up and back, and drooping ears.

Cattle and humans
Cattle are very important to the economies of many countries as well as to small farmers throughout the world. Millions of beef and dairy cattle throughout the world produce meat, milk, cheese, butter, and other products. Their skin is made into leather goods. In addition, they help plow farmers' fields and haul heavy loads.

Because of their importance, cattle are monitored closely to make sure they do not have any diseases that could affect them or be passed along to humans. Tuberculosis, a bacterial disease in cattle, is harmful to humans. It is spread through infected milk and milk products. However, the bacteria can be killed by pasteurization, which is a heat treatment process that kills disease-causing microorganisms. Foot-and-mouth disease causes sores in the mouth and between the toes of cattle. Texas fever is caused by a microscopic parasite carried by ticks. The parasite destroys the blood cells of the cattle.

Bovine Spongiform Encephalopathy (BSE), or mad cow disease, was first diagnosed in British cattle in about 1986. BSE attacks the nerve cells of the cattle's brain. Because there may be a link between BSE and a similar fatal brain disease in humans, known as Creutzfeldt-Jakob disease (CJD), cattle diagnosed with BSE are destroyed.

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The large, meat-eating dinosaur Ceratosaurus can be recognized by the large horn on its snout. This feature earned it the name Ceratosaurus, which means “horned lizard.” Although it was smaller, Ceratosaurus looked very much like its rival, Allosaurus. Ceratosaurus belongs to the group of meat-eating dinosaurs known as theropods.

Where and when Ceratosaurus lived
Ceratosaurus lived about 159 to 144 million years ago, during the period of the Earth's history known as the Jurassic. Remains of Ceratosaurus have been found in Africa and in North America in Colorado, Utah, and Wyoming. Like Allosaurus, Ceratosaurus lived in the fern savannas and wooded floodplains that had thick vegetation, where its plant-eating prey could be found.

Physical features
Ceratosaurus was a fierce-looking dinosaur that stood and walked on its two back legs. It could reach a length of more than 20 feet (6 meters) and stood about 6 12 feet (2 meters) tall. Ceratosaurus weighed up to 2 tons. In addition to the bony horn on its snout, Ceratosaurus also had a bony ridge above each eye. It had a short, thick neck. Its head was large but light for its size and had strong jaws and long, razor-sharp teeth. Ceratosaurus also had a row of bony plates that ran along its back, from its neck to the end of its long, thick tail. These bony plates looked like the small spiny ridges that run down the backs of modern iguanas. Ceratosaurus had short arms, but unlike other theropods, it had four long-clawed fingers on its front feet, instead of three. It also had three clawed toes on its back feet.

Behavior
Ceratosaurus was the sprinter of the dinosaur world. Using its powerful back legs, it could take off and run at high speeds. This ability allowed it to outrun enemies and to capture prey with a sudden burst of speed. Scientists believe that Ceratosaurus was also a scavenger that fed on the dead bodies of other dinosaurs. Fossil findings show that Ceratosaurus probably hunted alone, rather than in packs. Some scientists believe that male Ceratosaurus, during the breeding season, may have used the horns on their snouts in combat with one another. Other scientists argue, however, that because it was so lightweight, the horn may have been used simply for show. Males may have bobbed their heads up and down to show off their horn, much in the way some modern reptiles do. Fossil findings show that male Ceratosaurus were larger and stronger than the females. Ceratosaurus reproduced by laying eggs.

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Over short distances, no animal on Earth can outrun the cheetah. This large, spotted cat can sprint at more than 60 miles (100 kilometers) per hour, and it requires only a few seconds to reach top speed. The scientific name of the cheetah is Acinonyx jubatus.

Where cheetahs live
Cheetahs can live in a variety of places, but they especially like open grasslands. They use hills or low tree branches as lookout points. Cheetahs were once found throughout Africa except for in the rain forests and part of the Sahara. Now, however, African cheetahs are found only in scattered parts of central, eastern, and southern Africa. Cheetahs also used to roam over much of western and southern Asia, from the Middle East to India. Today Asian cheetahs are limited to a small number in Iran and the surrounding area.

Physical features
In the Hindi language of India, cheetah means “spotted one.” The name refers to the small black spots on the cheetah's sandy yellow fur. In one rare variety, the king cheetah, some of the spots run together to create a blotched or striped pattern. The only part of a cheetah without spots is the white belly. The cheetah's tail is marked with dark rings. Because of its spots, the cheetah is sometimes confused with another cat, the leopard. One difference between the two is that the cheetah's spots are not clustered in groups like those of the leopard. Another unique feature of the cheetah is the black lines running from the eyes to the corners of the mouth. These are sometimes called tear marks.

The cheetah measures about 55 inches (140 centimeters) long from head to tail. The tail adds another 30 inches (76 centimeters) to the length. The animal stands about 31 inches (80 centimeters) tall at the shoulder. It is a slender cat that weighs about 110–130 pounds (50–60 kilograms). Males tend to be larger than females.

A cheetah's body is built for speed. Several special traits, or adaptations, help the cheetah while sprinting. Long legs allow the cheetah to take big strides. Ridged footpads, along with specially adapted claws, help it to grip the ground. The cheetah is the only kind of cat that cannot pull its claws completely back, meaning that its claws, like those of a dog, are always exposed. The animal's large heart and lungs deliver the oxygen needed for sprinting.

Behavior
Cheetahs live alone or in small groups. The groups generally consist of either a female with her young or a few males. A female lives alone when it is not raising cubs. Cheetah groups generally stay out of each other's territory.

Although most cats are active at night, cheetahs usually hunt in the morning or late afternoon. Their method of hunting is also unique. Most cats pounce on a prey animal after either lying in wait for it to approach or sneaking up on it. The cheetah, however, uses its speed to chase down its prey, which is often a small antelope. After first creeping up on an animal, a cheetah sprints at it from a few hundred feet away. The cheetah can overtake even the fastest prey, but it can keep up the chase for only about 1,300–1,600 feet (400–490 meters) before tiring. Often the prey is able to escape. When the cheetah does catch its prey, it trips the animal with a blow to its back legs. The cheetah kills the prey by biting into its throat.

A cheetah that has just made a kill is often exhausted and weak. Lions or other rival predators sometimes take advantage of this period of weakness by stealing the cheetah's catch.

Life cycle
Male and female cheetahs come together only to breed. About 90 to 95 days after mating, a female cheetah usually gives birth to about two to four cubs. The newborn cubs are blind and helpless. Within about 12 days, however, they open their eyes and begin to walk. For the first few months of life a baby cheetah has a dark-spotted coat with long, blue-gray hair on the head, neck, and back. The coat changes as the cub grows.

Many cheetah cubs fall victim to other predators such as lions and hyenas. The survivors stay with their mother for 15–17 months while they learn to hunt. After about two years the young cheetahs are ready to breed. Some cheetahs in zoos have reached the age of 19, but most do not live that long.

Relationship with humans
In ancient times people learned that cheetahs could be tamed and trained as hunting companions. The ancient Egyptians used cheetahs in this way, and later the tradition passed to the rulers of India and Europe. For this reason cheetahs are sometimes called hunting leopards. The hunters released a cheetah in sight of a prey animal. If the cheetah's chase was successful, the hunters gave it part of the catch and took the rest for themselves. All cheetahs used for this purpose were taken from the wild, causing a steady decline in cheetah populations. Adding to the problem was the hunting of cheetahs themselves for their fur. Eventually cheetahs disappeared from India and other places.

Today cheetahs continue to face a number of threats to their survival. Farmers trap or kill cheetahs because the animals sometimes attack livestock. Another danger is the expansion of human settlements onto the land where cheetahs live. This reduces the living space of both the cheetah and the animals on which it preys. Conservation groups are working with farmers to come up with new ways to deal with the animals. They have also taken steps to preserve the cheetah's remaining habitat.

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Thought to be the closest living relative to humans, the chimpanzee is a type of African great ape. Chimpanzees are very smart, social, and active animals. Their scientific name is Pan troglodytes.

Where chimpanzees live
Chimpanzees are found in Africa in the countries that lie along the equator. They live mostly in tropical rain forests. They sometimes live in drier woodland savannas as well.

Physical features
Individual chimpanzees vary in size and appearance. They usually stand about 3 to 512 feet (1 to 1.7 meters) tall and weigh about 57 to 154 pounds (26 to 70 kilograms). Males are usually larger than females. A chimpanzee's arms are longer than its legs, reaching just below the knees when the animal stands.

Chimpanzees have a coat of brown or black hair. Their face, ears, hands, and feet are bare. Their skin color is black, though it may be pink or brown in younger animals. Their head is covered with just a little bit of hair, which both males and females lose as they grow older. The top of the head is rounded. Their ears stick out, and their lips protrude. Their jaw projects out beyond the upper part of the face.

Behavior
Chimpanzees spend time both in trees and on the ground. In trees, they use both their hands and their feet to move, or they swing by their arms from branch to branch. If they must go long distances, they usually travel on the ground. Chimpanzees can walk upright, but they more often lean on the knuckles of their hands and walk on all fours. Chimpanzees are active during the day. At night they usually sleep in the trees in nests that they make out of branches and leaves.

Chimpanzees do not usually eat meat. Their diet is made up mostly of fruits, berries, leaves, and seeds. They sometimes eat termites and ants and occasionally hunt and eat young baboons and bush pigs.

No animals besides humans use tools as well as chimpanzees. Chimpanzees poke twigs, grass, or other objects into ant and termite nests, pull out the tool, and eat the insects that cling to it. They also use leaves to soak up drinking water and to clean themselves. Young chimpanzees probably learn how to use tools by watching and imitating adults.

Chimpanzees are very social animals that live in groups known as communities. Each community has a male leader and 15 to 120 members, usually divided into smaller groups. Those groups continually change, and relationships between them are generally friendly. Members of a community are free to come and go as they wish. Different communities, however, often do not get along with each other. Chimpanzees of one community sometimes attack and fight chimpanzees of another community.

Adult chimpanzees in the same community regularly groom each other's fur. That behavior helps them to bond with one another. Chimpanzees communicate by facial expressions, gestures, and many different sounds, including screams, hoots, grunts, and roars.

Life cycle
Mating can happen at any time of year. Female chimpanzees give birth to a single young after a pregnancy of about eight months. A newborn weighs about 4 pounds (1.8 kilograms), is almost helpless, and clings to the fur of the mother's belly when she moves. From about 6 months to 2 years, the youngster rides on the mother's back. Chimpanzees can live up to about 50 years.

Chimpanzees and humans
The number of chimpanzees in the wild has greatly fallen, mainly because of human behavior. Humans hunt chimpanzees, destroy their habitat through logging and farming, and capture them for use in zoos and research laboratories. Chimpanzees are now considered an endangered species, a type of animal that is at risk of dying out.

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Closely related to squirrels, chipmunks can be told apart by their small size, striped backs, large cheek pouches, and habit of staying on the ground. Chipmunks are burrowing rodents. They keep nuts and other food stored in their burrows for winter.

Where chipmunks live
Chipmunks may be found in a wide range of habitats, including woodlands, mountains, and plains. All but one species, or type, are North American. The eastern chipmunk ranges from Canada southward to Georgia and westward to the Great Plains. Many different kinds of western chipmunks live in western North America. The one species that lives outside of North America is the Asiatic chipmunk, which is found in northern Asia and parts of eastern Europe.

Physical features
All chipmunks are quite small. The eastern chipmunk is 512 to 712 inches (14 to 19 centimeters) long. Its bushy tail is more than half as long as its body. It weighs only about 212 to 5 ounces (71 to 142 grams). The western and Asiatic chipmunks are even smaller.

Chipmunks can be identified by their colors and stripes. The eastern chipmunk is reddish brown with five dark stripes on its back. Between the dark stripes are two brown and two white stripes. The western and Asiatic chipmunks come in various colors, but many are yellowish. Like the eastern chipmunk, they have five dark stripes. However, all four areas between the stripes are whitish.

Behavior
Although chipmunks prefer to live on the ground, they are good tree climbers and can also swim. They make a shrill chattering sound. They like to eat nuts, seeds, wild fruits, and berries. They have inner cheek pouches that they can stuff with food. They carry the food home and store it for the winter.

Each chipmunk has its own burrow in the middle of its own territory. The burrow is dug under rocks or tree roots or logs. It contains at least two chambers—one a storeroom for nuts and the other a leaf-lined nest. Chipmunks sleep during most of the winter, but not deeply enough to be considered true hibernators. From time to time they get up to eat.

Life cycle
Mating usually occurs in late winter or early spring. One month later, the female chipmunk gives birth to four or five young. In warmer regions there may be two mating seasons in the same year. After about one month, the young first leave the nest. After about two months, they go out on their own, and after three months they are fully grown.

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Where cobras live
Cobras live in warm regions throughout Asia, Australia, and Africa. Some dwell in grasslands, forests, or deserts. Others live in trees or along the shores of lakes.

Physical features
The bodies of cobras are medium to large in size and usually a single color or spotted. The king cobra of Asia is the world's longest poisonous snake. It can reach a length of about 18 feet (5.5 meters).

All types of cobras are able to lift up the skin behind their head so that it looks like a hood. When the cobra is threatened, it extends its long, flexible back ribs sideways and forward. This stretches the skin to create the hood. The size of the hood varies with the type of snake. Some cobras have distinct markings on their hoods.

All cobras also have short, hollow front fangs that deliver venom to their prey. Most cobras have holes at the bottom of their fangs, but the African ringhals and other spitting cobras have small holes at the front. They can accurately squirt a stream of venom at high speed into an intruder's eyes. Some large cobras can spit venom a distance of 7 feet (2 meters) or more. The venom does not harm the skin, but it can cause intense pain and permanent blindness in the eyes if they are not promptly treated. The snake spits the venom to distract an intruder while it retreats. Such snakes also inject venom into prey through a bite.

Behavior
Cobras hunt in the evening and at night, often hiding in animal burrows and termite mounds. Their prey includes mammals, birds, snakes, lizards, frogs, and even fish. The small mammal known as the mongoose is an enemy of the cobra. It attacks the cobra quickly from above to avoid the snake's strike.

A cobra takes on a fierce posture when threatened. It rears its head up off the ground to almost one-third of its body length and spreads its hood. Some cobras add a hiss to this posture, and the king cobra gives a loud growl. It is from this position that the cobra strikes in self-defense.

Life cycle
Females lay up to several dozen eggs and hide them in leaf piles and other warm, moist places. King cobras loop their bodies to scoop vegetation and build a nest. Some cobras, including king cobras, guard their eggs until they hatch.

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Corals are small marine animals that stay in one place throughout their adult lives. These animals produce a hard skeleton made of calcium carbonate, or limestone. The skeletal material, which outlives the animal, is also called coral. Corals can be very colorful underwater, but most types fade when they die or are removed from the water. The red coral, found in the Mediterranean Sea and in the coastal waters of Japan, does not lose its color when removed from the water. Because of this quality it has been used in jewelry for centuries.

Where corals live
Corals live in all the oceans of the world. Many types grow in colonies that continue to enlarge year after year. Other types are solitary, meaning that they live alone. Several different types of corals can together form enormous colonies. These colonies are called coral reefs, coral islands, and coral atolls. The largest reefs are found in the warmer portions of the Pacific and Indian oceans. However, coral reefs are also found in the Caribbean and in the Gulf of Mexico as far north as southern Florida.

Coral reefs are composed of different types of corals. The reefs create underwater habitats that are essential for many species of marine organisms. Certain kinds of fish spend their life among the corals, using them as a refuge from predators. The largest coral reef in the world, the Great Barrier Reef off the coast of Australia, is more than 1,250 miles (2,000 kilometers) long. More than 350 species of coral have been found in the Great Barrier Reef.

Physical characteristics
Coral reefs have different shapes and patterns because of the growth pattern of the millions of tiny individual animals that make up a colony. Reefs can look like beautiful underwater gardens. Some corals resemble the tendrils of plants, while some may look like leaves. The brain coral is nearly spherical and has grooves that make it look like a human brain. Corals with flat, fan-shaped structures that spread out from a narrower base are called sea fans. The organ-pipe corals, which are found in the tropical oceans of the Indo-Pacific, are typically long rigid tubes.

The corals' skeletons, external or internal, have a stonelike, horny, or leathery texture. The body of a coral animal consists of a polyp—a hollow, cylindrical structure attached at its lower end to some surface. The largest of the solitary polyps grows to a diameter of about 10 inches (25 centimeters). The polyps of the corals that form reefs range from 0.04 to 1.2 inches (0.1 to 3 centimeters) in diameter.

Life cycle
Corals reproduce in two different ways. In one process, fertilized eggs develop into tiny, swimming organisms called planulae. Planulae eventually settle on the bottom of the ocean, on a rock or on another coral, and develop into polyps. Each polyp builds a limestone skeleton attached to the surface on which the polyp has landed. After the coral establishes itself, the upper part of the body becomes dome-shaped and develops a stomach and mouth.

Reproduction also can occur by budding. A bud develops the body of a polyp and remains attached there. A colony develops by the constant addition and growth of new buds. As new polyps develop, the older, underlying polyps die, leaving behind their skeletons. In some kinds of coral the buds may break away to become separate individuals. Vast coral colonies are built by budding, with the animals connected by their extensive skeletal network.

Food habits
Small marine organisms are the major food of corals. At the free end of the polyp is a mouth surrounded by tentacles. The tentacles gather food from the surrounding waters. Corals are also armed with specialized stinging structures, called nematocysts, that paralyze their prey. Nutrients are passed from individual corals on the outside of a colony to those on the inside.

Ecological issues
By the 1990s coral reefs off the coasts of more than 20 countries were being destroyed for a number of reasons. Rising water temperature is said to cause bleaching, which the corals cannot withstand. Oil spills and chemical pollution also are a major threat to corals. Long-term damage occurs when stands of coral are broken by freighters or boat anchors. Overfishing has caused the loss of coral-protecting sea urchins. This has left the coral vulnerable to the crown of thorns, a kind of coral-eating starfish.

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Coral snakes are poisonous snakes marked with bands of red, black, and yellow or white. These markings warn other animals that the snake is dangerous. The short, hollow fangs of coral snakes deliver a powerful venom that attacks the nervous system and can be deadly to human beings.

Where coral snakes live
About 65 kinds of coral snakes live in North and South America. They inhabit an area from the southern United States to central Argentina. Coral snakes live in a variety of places, including grasslands, rocky hillsides, tropical forests, and deserts.

Physical features
The bodies of coral snakes are made for burrowing, and they have narrow heads and slender bodies with long, pointed tails. Most coral snakes measure less than 3 feet (0.9 meter) long, but some South American varieties can grow longer than 4 feet (1.2 meters).

The eastern coral snake lives from the southeastern United States to northeastern Mexico. It has a black snout and narrow yellow bands separating wide bands of red and black. A few poisonous snakes in Africa, Australia, Asia are also known as coral snakes, but their coloring and markings vary and include stripes and spots.

Behavior
Coral snakes remain hidden most of the time, but they do come out to prowl and feed on other snakes and small lizards. When threatened, they may hide their heads in their coils and curl up their tails to look like heads. Some coral snakes respond to danger by making jerky movements or trying to bite. Others expel air from an opening called the vent, which makes a popping or gurgling sound.

Female coral snakes bury their eggs in leaves or other material. After hatching, the snakes use their rounded snouts to burrow in animal tunnels, decaying logs and leaves, and under rocks.