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The wolf ( Canis lupus) is a mammal of the order Carnivora. It is sometimes called timber wolf or grey wolf.

It is the ancestor of the domestic dog. A recent study found that the domestic dog is descended from wolves tamed less than 16,300 years ago south of the Yangtze River in China.

There are many different wolf subspecies, such as the Arctic wolf. Some subspecies are listed on the endangered species list, but overall, Canis lupus is IUCN graded as 'least concern'.

Appearance

Adult wolves are usually 1.4 to 1.8 metres (4.6 to 5.9 ft) in length from nose to tail depending on the subspecies. Wolves living in the far north tend to be larger than those living further south. As adults they may weigh typically between 23 to 50 kilograms (51 to 110 lb). The heaviest wolf recorded weighed 86 kilograms (190 lb).

The wolf has a long muzzle, short ears, long legs, and a long bushy tail.

Wolves usually measure 26-38 inches at the shoulder. Wolves have fur made up of two layers. The top layer is resistant to dirt, and the under-layer is water resistant. The color of their fur can be any combination of grey, white, taupe, brown, and black.

Wolves live in groups called "packs". They are pack hunters. The members of the pack are usually family members, often just the parents and offspring. Wolves that are not family may join if they do not have a pack of their own. Packs are usually up to 12 wolves, but they can be as small as two or as large as 25. The leaders are called the parent (breeding) male and the parent (breeding) female. Their territory is marked by scent and howling; they will fight any intruders.

Young wolves are called 'pups' or 'whelps'. Adult females usually give birth to five or six pups in a litter.

Wolves make a noise called a howl. They howl to communicate with each other from long distances and to mark the edges of their territory. Wolves have a complicated body language.

Wolves can run very fast and far. A wolf can run 20-30 miles in a day.

Grey wolves can live six to eight years. They can live in captivity for up to 17 years.

Wolves are carnivores and eat mostly medium to large size hoofed animals (unguligrades), but they will also eat rodents, insectivores and foxes. Some wolves have been seen eating salmon, seals, beached whales, lizards, snakes and birds. They also eat moose, bison, deer and other large animals.

Wolves can eat about 20 pounds (approx. 9 kg) of meat in one meal. (About 100 hot dogs).

Wolves usually stalk old or sick animals. It is easier for the wolves to take down the sick because they are slower and less powerful. They do not always catch what they stalk. They may go days without food. Sometimes only one out of twelve hunts are successful.

The alpha male and female feed first. Then the other members feed. Sometimes (especially if the prey they have killed is large) wolves may store food and come back that day to feed on it. Wolves have very sharp teeth which helps them tear large chunks of meat from a dead animal. They will eat up to 2/7 their body weight. Wolves will also swallow food and then bring it back up for pups to eat.

Wolves are found in Europe, Asia and North America. They can live in forests, deserts, mountains, tundra, grasslands and sometimes around towns and cities.

Social structure

The wolf is a social animal. Its populations consist of packs and lone wolves. Most lone wolves disperse from packs to form their own or join another one.

The wolf's basic social unit is the nuclear family consisting of a mated pair accompanied by their offspring. The average pack size in North America is eight wolves and in Europe 5.5 wolves. The average pack across Eurasia consists of a family of eight wolves (two adults, juveniles, and yearlings), or sometimes two or three such families, with examples of exceptionally large packs consisting of up to 42 wolves being known.

Offspring typically stay in the pack for 10-54 months before dispersing. Some stay in the vicinity of the parental group, while other individuals may travel great distances of upwards of 206 km (128 mi), 390 km (240 mi), and 670 km (420 mi) from their natal (birth) packs. Wolf packs rarely adopt other wolves into their fold and typically kill them. In the rare cases where other wolves are adopted, the adoptee is almost invariably an immature animal of one to three years old, and unlikely to compete for breeding rights with the mated pair. This usually occurs between the months of February and May. Adoptee males may mate with an available pack female and then form their own pack. In some cases, a lone wolf is adopted into a pack to replace a deceased breeder.

Wolves are territorial animals. They generallly establish territories far larger than they require to survive in order to have a steady supply of prey. Territory size depends on the amount of prey available and the age of the pack's pups.

Wolf packs travel constantly in search of prey, covering roughly 9% of their territory per day. Wolf packs are typically settled, and usually leave their territory only when there is severe food shortage.

Communication

Wolves communicate using vocalizations, body postures, scent, touch, and taste.

The phases of the moon have no effect on wolf vocalization, and despite popular belief, wolves do not howl at the moon. Wolves howl to assemble the pack usually before and after hunts, to pass on an alarm particularly at a den site, to locate each other during a storm, while crossing unfamiliar territory, and to communicate across great distances. Wolf howls can under certain conditions be heard over areas of up to 130 km ² (50 sq mi).

Other vocalizations include growls, barks and whines. Wolves do not bark as loudly or continuously as dogs do in confrontations, rather barking a few times and then retreating from a perceived danger.

Scent marking is more effective at advertising territory than howling and is often used in combination with scratch marks. Wolves increase their rate of scent marking when they encounter the marks of wolves from other packs. Lone wolves will rarely mark, but newly bonded pairs will scent mark the most. These marks are generally left every 240 m (260 yd) throughout the territory on regular travelways and junctions. Such markers can last for two to three weeks, and are typically placed near rocks, boulders, trees, or the skeletons of large animals.

Reproduction

Wolves are monogamous. Mated pairs usually remain together for life. Should one of the pair die, another mate is found quickly.

Wolves become mature at the age of two years. The age of first breeding in wolves depends largely on environmental factors: when food is plentiful, or when wolf populations are heavily managed, wolves can rear pups at younger ages to better exploit abundant resources. Females are capable of producing pups every year, one litter annually being the average.

Dens are usually constructed for pups during the summer period. When building dens, females make use of natural shelters like fissures in rocks, cliffs overhanging riverbanks and holes thickly covered by vegetation. Sometimes, the den is the appropriated burrow of smaller animals such as foxes, badgers or marmots. An appropriated den is often widened and partly remade. On rare occasions, female wolves dig burrows themselves, which are usually small and short with one to three openings.

The den is usually constructed not more than 500 m (550 yd) away from a water source. It typically faces southwards where it can be better warmed by the sun, and the snow can thaw more quickly. Resting places, play areas for the pups, and food remains are commonly found around wolf dens.

The gestation period lasts 62-75 days with pups usually being born in the spring months or early summer in very cold places such as on the tundra. Young females give birth to four to five young, and older females from six to eight young and up to 14.

Newborn wolf pups look similar to German Shepherd Dog pups. They are born blind and deaf and are covered in short soft grayish-brown fur. They weigh 300-500 g (- oz) at birth and begin to see after nine to 12 days. The milk canines erupt after one month. Pups first leave the den after three weeks. At one-and-a-half months of age, they are agile enough to flee from danger. Mother wolves do not leave the den for the first few weeks, relying on the fathers to provide food for them and their young. Pups begin to eat solid food at the age of three to four weeks. They have a fast growth rate during their first four months of life: during this period, a pup's weight can increase nearly 30 times. Wolf pups begin play-fighting at the age of three weeks, though unlike young coyotes and foxes, their bites are gentle and controlled. Actual fights to establish hierarchy usually occur at five to eight weeks of age. This is in contrast to young coyotes and foxes, which may begin fighting even before the onset of play behaviour. By autumn, the pups are mature enough to accompany the adults on hunts for large prey.

Arctic wolf

The Arctic wolf may be a subspecies of the grey wolf. They live in the Canadian part of the Arctic Circle, as well as Greenland and Iceland.

The habitat of Arctic wolves is very hostile. Not much is known about their lifestyle. They are more friendly than other wolves, but they can still be very aggressive.

Their winter fur is highly resistant to the cold. Wolves in northern climates can rest comfortably in open areas at −40 °C (−40 °F) by placing their muzzles between the rear legs and covering their faces with their tail. Wolf fur provides better insulation than dog fur, and does not collect ice when warm breath is condensed against it. Since about 1930, the skull of many Arctic wolves has become smaller. This might be because of hybridization between wolves and dogs. They are 3 feet (0.91 m) tall when they're adults. Adult arctic wolves weigh about 75 to 120 pounds (34 to 54 kg). Arctic wolves live in a group of 7-20 wolves. They may live up to 5-10 years in the wild. They can live for 14 years if they are well cared for in a zoo.

Wolves and humans

Even though many people think that wolves are terrible, mean creatures, they are actually much gentler than many people imagine. The main reason wolves become violent is because they may be sick or to protect other wolves in the pack. Many people around the world, especially in Canada and Alaska, have huskies for pets: they are a close relative of the wolf.

A few years ago wolves were put back into Yellowstone National Park in Wyoming to breed, because they were becoming endangered. The wolves have been very successful in the park. There had been no wolves there for a long time, because of hunting and poisoned water. Many people were not happy about this because they were afraid that the wolves would eat the sheep and cows near the park. However, wolves only eat livestock when they can not find wild prey.

Human hunting of wolves

Theodore Roosevelt said wolves are difficult to hunt because of their elusiveness, sharp senses, high endurance, and ability to quickly incapacitate and kill a dog. Historic methods included killing of spring-born litters in their dens, coursing with dogs (usually combinations of sighthounds, Bloodhounds and Fox Terriers), poisoning with strychnine, and trapping.

A popular method of wolf hunting in Russia involves trapping a pack within a small area by encircling it with fladry poles carrying a human scent. This method relies heavily on the wolf's fear of human scents, though it can lose its effectiveness when wolves become accustomed to the odor. Some hunters can lure wolves by imitating their calls. In Kazakhstan and Mongolia, wolves are traditionally hunted with eagles and falcons, though this practice is declining, as experienced falconers are becoming few in number. Shooting wolves from aircraft is highly effective, due to increased visibility and direct lines of fire. Several types of dog, including the Borzoi and Kyrgyz Tajgan, have been specifically bred for wolf hunting.

Extinction in Britain

Wolves in Britain were all killed after centuries of hunting. The last wolves survived in the Scottish Highlands. There is a legend that the last one was killed there in 1743 by a character called MacQueen.

Within the past ten years, there have been studies that are in favour of allowing new wolves to come and live in the English countryside and Scottish Highlands again. One study was in 2007. Researchers from Norway, Britain, and Imperial College London decided that wolves would help add back plants and birds that now are eaten by deer. The wolves would keep the deer population lower. People were generally positive, but farmers living in rural areas wanted to be paid for livestock that were killed by the wolves.

As pets and working animals

Wolves and wolf-dog hybrids are sometimes kept as exotic pets. Although closely related to domestic dogs, wolves do not show the same tractability as dogs in living alongside humans, being generally less responsive to human commands and more likely to act aggressively. A person is more likely to be fatally mauled by a pet wolf or wolf-dog hybrid than by a dog.

In popular culture

The wolf is a common motif in the myths. The Ancient Greeks associated wolves with Apollo, the god of light and order. The Ancient Romans connected the wolf with their god of war and agriculture Mars, and believed their city's founders, Romulus and Remus, were suckled by a she-wolf. Norse mythology includes the feared giant wolf Fenrir, and Geri and Freki, Odin's faithful pets.

In Chinese astronomy, the wolf represents Sirius and guards the heavenly gate. In China, the wolf was traditionally associated with greed and cruelty and wolf epithets were used to describe negative behaviours such as cruelty ("wolf's heart"), mistrust ("wolf's look") and lechery ("wolf-sex"). In both Hinduism and Buddhism, the wolf is ridden by gods of protection. In Vedic Hinduism, the wolf is a symbol of the night and the daytime quail must escape from its jaws. In Tantric Buddhism, wolves are depicted as inhabitants of graveyards and destroyers of corpses.

In the Pawnee creation myth, the wolf was the first animal brought to Earth. When humans killed it, they were punished with death, destruction and the loss of immortality. For the Pawnee, Sirius is the "wolf star" and its disappearance and reappearance signified the wolf moving to and from the spirit world. Both Pawnee and Blackfoot call the Milky Way the "wolf trail". The wolf is also an important crest symbol for clans of the Pacific Northwest like the Kwakwakaʼwakw.

The concept of people turning into wolves, and the inverse, has been present in many cultures. One Greek myth tells of Lycaon being transformed into a wolf by Zeus as punishment for his evil deeds. The legend of the werewolf has been widespread in European folklore and involves people willingly turning into wolves to attack and kill others. The Navajo have traditionally believed that witches would turn into wolves by donning wolf skins and would kill people and raid graveyards. The Dena'ina believed wolves were once men and viewed them as brothers.

In fable and literature

Images for kids

A Canis etruscus skull in the Montevarchi Paleontological Museum

A wolf carrying a caribou hindquarter, Denali National Park, Alaska

The Capitoline Wolf, sculpture of the mythical she-wolf feeding the twins Romulus and Remus, from the legend of the founding of Rome, Italy, 13th century AD. (The twins are a 15th-century addition.)

Country children surprised by a wolf (1833) by François Grenier de Saint-Martin

In Spanish: Canis lupus para niños

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The polar bear ( Ursus maritimus) is a large bear which lives in the Arctic. It is also called white bear or northern bear. It has black skin under the white fur. They are strong and fast, and can run as fast as 25 miles (40 km) an hour for a short distance.

Appearance

Polar bear fur is made up of a layer of dense underfur and an outer layer of "guard hairs", which appear white to tan but are actually translucent. The fur keeps them very warm. The skin is not white; it is black. Therefore, they can absorb sunlight efficiently. They are strong and can swim very well. Polar bears are similar in size to a normal bear but have a slimmer neck, longer legs and fur.

The only other bear of comparable size to the polar bear is the Kodiak bear, which is a subspecies of brown bear. Adult male polar bears weigh 350-700 kg (770-1,500 lb) and measure 2.4-3 metres (7 ft 10 in-9 ft 10 in) in total length. Around the Beaufort Sea, however, mature males reportedly average 450 kg (1,000 lb). Adult females are roughly half the size of males and normally weigh 150-250 kg (330-550 lb), measuring 1.8-2.4 metres (5 ft 11 in-7 ft 10 in) in length. Elsewhere, a slightly larger estimated average weight of 260 kg (570 lb) was claimed for adult females. When pregnant, however, females can weigh as much as 500 kg (1,100 lb). The polar bear is among the most sexually dimorphic of mammals, surpassed only by the pinnipeds such as elephant seals. The largest polar bear on record, reportedly weighing 1,002 kg (2,209 lb), was a male shot at Kotzebue Sound in northwestern Alaska in 1960. This specimen, when mounted, stood 3.39 m (11 ft 1 in) tall on its hindlegs. The shoulder height of an adult polar bear is 122 to 160 cm (4 ft 0 in to 5 ft 3 in). While all bears are short-tailed, the polar bear's tail is relatively the shortest amongst living bears, ranging from 7 to 13 cm (2.8 to 5.1 in) in length.

Compared with its closest relative, the brown bear, the polar bear has a more elongated body build and a longer skull and nose. As predicted by Allen's rule for a northerly animal, the legs are stocky and the ears and tail are small. However, the feet are very large to distribute load when walking on snow or thin ice and to provide propulsion when swimming; they may measure 30 cm (12 in) across in an adult. The pads of the paws are covered with small, soft papillae (dermal bumps), which provide traction on the ice. The polar bear's claws are short and stocky compared to those of the brown bear, perhaps to serve the former's need to grip heavy prey and ice. The claws are deeply scooped on the underside which assists in digging in the ice of the natural habitat. Research of injury patterns in polar bear forelimbs found injuries to the right forelimb to be more frequent than those to the left, suggesting, perhaps, right-handedness. Unlike the brown bear, polar bears in captivity are rarely overweight or particularly large, possibly as a reaction to the warm conditions of most zoos.

They are mostly carnivorous. They eat mostly seals and fish. When Polar bears hunt, they often wait at holes in the ice, where the seals come up to breathe. They can live off of one seal for many days, but it will make them hungry if they do.

Polar bears live alone. Polar bears are black with clear fur, so in daylight, they appear white; at night, they are invisible.

Young Polar bears stay with their mothers for 1-2 years, and they become mature when they are 5-6 years old. People think Polar bears can become 25-30 years old in nature, but in captivity (for example, in zoos), they can become up to 45 years old.

Polar bears live in countries in the Arctic Circle, including these:

Polar bear cubs

The breeding time is 8 months. The babies are born six weeks after their mother mates. At birth, a baby cub weighs less than 2 pounds (0.9 kilograms). The mother feeds the babies milk, which makes them grow fast, and after 10 weeks, the cubs weigh about 20 to 25 pounds (9.1 to 11.4 kilograms). Young polar bears wrestle in the snow to build their strength and skills. They practice using their strong paws, and they show off their big, sharp teeth.

Mother polar bears will do anything to protect their young. They can kill a predator with just one swat of their powerful front paws. Scientists have even seen a mother polar bear stand up and leap at a helicopter to keep it away from her cubs.

During the first year, the cubs begin to eat solid food but still nurse from their mother. They begin to learn to hunt and swim. But they cannot live on their own. By the time they are two years old, the cubs have grown into large bears. They leave their mother and strike off into territory of their own. They hunt and live alone. But they play with other bears they meet. Polar bears are ready to mate when they are five or six years old. They are adults by this time and weigh 330 to 660 pounds (150 to 300 kilograms).

Polar bear adults

Both male and female polar bears live to be as much as 30 years old (in a zoo). Polar bears have 42 teeth.

As adults, male bears fight with each other over a female. Each male fluffs out his coat of fur to make himself look bigger. Then, he swaggers along, growling, to scare off his rival. Polar bear scientists call this "the cowboy walk." The polar bear eats seals, fish and fruits (berries). They can be up to 250cm long and 160cm tall and weigh up to 600kg.

When two polar bears meet, they have a special way of greeting each other. They circle around each other for a while, grunting. Then they come closer and touch noses.

The polar bear was the most dangerous animal to hunt. It was also greatly respected for its strength and spirit. The bear's blubber, meat, and fur all help the Inuit survive. The Inuit gave thanks and respect in turn. After a hunt, they held a celebration that lasted for several days. Then, a polar bear dance was held. Finally, the bear's skull was set on an ice floe to release its spirit back into the Arctic.

A polar bear's paws are perfect snowshoes for them. The bottoms are wide and covered with fur to help keep the bear from slipping. The sharp claws help grip the ice.

A polar bear can crawl across ice too thin for a human to walk on. They spread out their legs and lay their bellies flat on the ice. Then they use their claws to slowly push themselves across the ice.

Polar bears mate in April or May. The cub is born in December, when the mother is hibernating. The cub stays in the den with the mother until March, then, they all come out. They eat immediately after hibernating. Sometimes, because of global warming, this is impossible and the cubs die before they have had a chance to live. The cub leaves its mother in 2-3 years.

Life expectancy

Polar bears rarely live beyond 25 years. The oldest wild bears on record died at age 32, whereas the oldest captive was a female who died in 1991, age 43. The causes of death in wild adult polar bears are poorly understood, as carcasses are rarely found in the species's frigid habitat. In the wild, old polar bears eventually become too weak to catch food, and gradually starve to death. Polar bears injured in fights or accidents may either die from their injuries, or become unable to hunt effectively, leading to starvation.

The polar bear's liver contains a lot of vitamin A. Inuit people knew that eating the liver could cause sickness and death. Several groups of European polar explorers were seriously ill after eating livers. The symptoms included drowsiness, wanting to sleep, being irritable, headaches, and vomiting. After 24 hours, people's skin began to peel off.

Indigenous folklore

For the indigenous peoples of the Arctic, polar bears have long played an important cultural and material role. Polar bear remains have been found at hunting sites dating to 2,500 to 3,000 years ago and 1,500-year-old cave paintings of polar bears have been found in the Chukchi Peninsula. Indeed, it has been suggested that Arctic peoples' skills in seal hunting and igloo construction has been in part acquired from the polar bears themselves.

The Inuit and Alaska Natives have many folk tales featuring the bears including legends in which bears are humans when inside their own houses and put on bear hides when going outside, and stories of how the constellation that is said to resemble a great bear surrounded by dogs came into being. These legends reveal a deep respect for the polar bear, which is portrayed as both spiritually powerful and closely akin to humans. The human-like posture of bears when standing and sitting, and the resemblance of a skinned bear carcass to the human body, have probably contributed to the belief that the spirits of humans and bears were interchangeable.

The Nenets of north-central Siberia placed particular value on the talismanic power of the prominent canine teeth. These were traded in the villages of the lower Yenisei and Khatanga rivers to the forest-dwelling peoples further south, who would sew them into their hats as protection against brown bears. It was believed that the "little nephew" (the brown bear) would not dare to attack a man wearing the tooth of its powerful "big uncle", the polar bear.

Symbols and mascots

Their distinctive appearance and their association with the Arctic have made polar bears popular icons, especially in those areas where they are native. The Canadian two-dollar coin carries an image of a lone polar bear on its reverse side, while a special millennium edition featured three. Vehicle licence plates in the Northwest Territories in Canada are in the shape of a polar bear, as was the case in Nunavut until 2012; these now display polar bear artwork instead. The polar bear is the mascot of Bowdoin College, Maine; the University of Alaska Fairbanks; and the 1988 Winter Olympics held in Calgary. The Eisbären Berlin hockey team uses a roaring polar bear as their logo, and the Charlotte, North Carolina hockey team the Charlotte Checkers uses a polar bear named Chubby Checker as their mascot.

Coca-Cola has used images of the polar bear in its advertising, and Polar Beverages, Nelvana, Bundaberg Rum, Klondike bars, and Fox's Glacier Mints all feature polar bears in their logos.

Polar bears are popular in fiction, particularly in books for children or teenagers.

Images for kids

In Spanish: Ursus maritimus para niños

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Polar bears, also known as Ursus maritimus by their scientific name, are the largest carnivore living on land in the Arctic.

Even though we might think so, they don't live with the super cool penguins, who actually live in Antarctica.

Let's explore some polar bear facts!

Where are Polar Bears found?

There are five countries that are lucky to have polar bears and they are the United States, Canada, Russia, Greenland and Norway.

Funky names

They've got some pretty cool names that people refer to them by including (obviously) "Polar Bears". But other name are Sea Bears, White Bears or Beliy Medved in Russia, Isbjorn in Denmark, Lord of the Arctic, Ice Bear or Nanuk to the Inuits, which means an animal worthy of great respect.

Which name will you call the Polar Bear? Sadly they are on the vulnerable list of endangered species.

How do they hunt for food?

They are very big and powerful white bears. Some scientists think that they started to evolve about five million years ago from brown bear ancestors.

That is a seriously long time ago! They are brilliantly adapted for survival in their icy homes and they hunt seals in openings on the ice - called leads - or at breathing holes.

They wait silently for hours or days for seals to come to the surface.

If one bear ' owns' a large carcass, it might share it if the guests approach low-to-the-ground, circle the carcass slowly and touch the nose of the bear in charge.

How interesting is that...they need to do a dance for some food! A polar bear can also hunt by swimming beneath the ice.

They mostly eat seal blubber because of its high fat content but sometimes eat walruses and beached whales. If stranded on land, they will eat vegetation, geese, bird eggs and occasionally caribou.

They can survive for seven to ten days without food.

How large are polar bears?

An adult male normally weighs between 775-1,200 pounds (351-546 kilograms).

The largest polar bear ever recorded weighed 2,209 pounds (over 1,000 kilograms), which is about the same as an average car. That's unbelievable!

Adult females weigh about 330-650 pounds (150-295 kilograms).

More cool facts about Polar Bears

42 razor sharp teeth

Paws measuring up to 12 inches (about 30 centimeters) across. These paws distribute their weight when they're treading on thin ice. They also act as paddles and rudders when swimming.

An excellent sense of smell. They can sniff out their seal meal on the ice 20 miles (32 kilometers) away, or at a breathing hole more than half a mile away under water (which is just under one kilometer)

Excellent sight and hearing.

Polar bears are also very intelligent!

Polar Bear Cubs

Females usually have two cubs that stay with their mother for about two and a half years, learning to hunt and survive.

Polar Bears don't hibernate, but mother bears live in dens to raise their cubs, where they don't eat or drink during that time.

How do Polar Bears Communicate?

Polar Bears use body language and vocal sounds to have a chat to each other.

They sway their heads from side-to-side when they want to play; make chuffing sounds when stressed; loud roars, hisses or growls when they're angry and deep growls when they're defending food.

They also attack with lowered heads and ears laid back and move downwind to show submission.

Are Polar Bears Actually White?

Although Polar Bears appear white, their fur is actually transparent, and has a hollow core. It looks white because it reflects visible light. Under their fur, polar bear skin is actually black with a layer of fat about 4.5 inches (11.5 centimeters) thick.

This layer helps keep them warm under water.

Mother bears are reluctant to swim with young cubs during cold spring temperatures as the cubs don't have enough fat to keep warm; it's their dry fur that keeps them warm.

Polar bears look whitest when they are clean and in sunlight. Before molting, oils from the seals they eat can make them look yellow. In San Diego Zoo in 1979 polar bears turned green because of algae growing in their hollow hair shafts.

Luckily, they turned white again with the zoo fixing and algae.

Biologists gather information about Polar Bears by fitting them with plastic belting tracking collars. They stay flexible in cold temperatures.

Nowadays, GPS is used to track them and is accurate within 30 feet (10 meters).

Most collars are fitted with an automatic release mechanism and a clock set to drop off on a specific date.

Collars don't interfere with the bear's natural activities. Bears can be followed for a long time to learn about their movements, hunting patterns, distances covered, time spent on land and in the water, their use of habitat and the rate of survival of cubs.

Now aren't these just the coolest animals around? We hope you've learnt some cool stuff about Polar Bears!

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Polar Bear Facts For Kids Polar bears, also known as Ursus maritimus by their scientific name, are the largest carnivore living on land in the Arctic. Even though we might think so, they don't live with the super cool penguins, who actually live in Antarctica. Let's explore some polar bear facts!

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Approximate worldwide winter
distribution of polar bears (light gray).
Polar bears are distributed throughout most
ice-covered seas of the Northern Hemisphere.

Source: http://www.polarbearsinternational.org/
Ursus maritimus
The polar bear or the sea/ice bear are the world's largest land predators. They can be found in the Artic, the U.S. (Alaska), Canada, Russia, Denmark (Greenland), and Norway. Each of these countries either banned hunting or established rules for how many polar bears could be hunted within its own boundaries. These rules help keep polar bear populations stable. Today, 25,000 to 40,000 polar bears roam the Arctic.

Please note: The photos on this page have come from clipart CD's which allow use on educational internet sites and in school projects or they have been contributed by viewers.

You are free to use all of it in book reports or for your personal website.

See KidZone Bibliography for more information.

Around the age of four or five the female polar bear can start having babies. They usually only have two cubs and they have these babies in a cave they've dug in a large snow drift. They stay there over winter and come out in spring with the babies.

The babies are much smaller than human babies when they're born. They are the size of a rat and weigh little more than a pound. They can grow to full man size in a year if they have lots of food.

Pair of polar bear cubs.
photo by: US Fish and Wildlife

Male polar bears may grow 10 feet tall and weigh over 1400 pounds. Females reach seven feet and weigh 650 pounds. In the wild polar bears live up to age 25.

Despite what we think, a polar bear's fur is not white. Each hair is a clear hollow tube. Polar bears look white because each hollow hair reflects the light. On sunny days, it traps the sun's infrared heat and keeps the bear warm at 98 degrees F (when they're resting).

Polar bear fur is oily and water repellent. The hairs don't mat when wet, allowing the polar bears to easily shake free of water and any ice that may form after swimming.

Underneath the fur, a polar bear's skin is actually black -- the black skin soaks up the sun's heat and helps them stay warm.

Polar bears also have a 4 inch layer of fat underneath their skin. This prevents them from losing any of their heat. In fact, if you look at a polar bear with an infared camera, they are pretty close to invisible (in other words, they don't give off any heat!)

The smallest foot pad is the front track
and the larger is the hind track.

Polar bears have wide front paws with slightly webbed toes that help them swim. They paddle with their front feet and steer with their hind feet. Paw pads with rough surfaces help prevent polar bears from slipping up on the ice.

Polar bears have been known to swim 100 miles (161 kilometers) at a stretch.

Polar bears primarily eat seals. They often rest silently at a seal's breathing hole in the ice, waiting for a seal in the water to surface. Once the seal comes up, the bear will spring and sink its jagged teeth into the seal's head.

They have a special liver that allows them to process all of the seal fat they eat - seals store a lot of vitamin A in their blubber which allows them to survive and grow quickly. A polar bear's liver contains 10 times more vitamin A than any other animal on earth - their liver has evolved to allow them to process and eat all of the seal blubber they need to stay alive.

Sometimes the polar bear stalks its prey. It may see a seal lying near its breathing hole and slowly move toward it, then charge it, biting its head or grabbing it with its massive claws. A polar bear may also hunt by swimming beneath the ice.

Humans are the polar bears only predator. Baby polar bears often starve. In fact, 70 percent do not live to their third birthday. Sometimes seals are hard to find, especially in the summer when the ice has melted. All across the Arctic, man is moving in to mine oil and coal and there is less space for the polar bear to live. Oil spills can be very dangerous. A bear with oil on its coat cannot regulate its body temperature properly. If the bear eats the oil while grooming it could die.

Man made pollution is also a cause of death. At each stage of the food chain, pollutants get more concentrated. By the end when the polar bear eats the seal and it could be lethal.

Polar Bears are considered marine mammals -- just like seals, whales and dolphins. Although polar bears are related to the brown bear, they have evolved over time to live in cold northern arctic climates. Their population is on the decline and they are considered a "vulnerable" species.

photo by: US Fish and Wildlife

Protecting polar bears isn't just a matter of being nice. Their body is very different than most mammals -- they are able to process large amounts of fat (seal blubber) and are able to lose and gain large amounts of weight through the year without causing stress health problems. Scientists are studying them to see if they can provide a key to human diseases like diabetes and heart disease!

Scientific genus and species: Ursus maritimus

Class: Mammalia (mammals)

Order: Carnivora (carnivores)

Family: Ursidae (bear family)

Genus: Ursus

Species: maritimus (meaning "sea bear")

Polar Bear On-Line Jigsaw Puzzles:

(Puzzle 2: Polar Bear with cub)

< Giant Panda

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Approximate worldwide winter distribution of polar bears (light gray). Polar bears are distributed throughout most ice-covered seas of the Northern Hemisphere. Source: http://www.polarbearsinternational.org/ Ursus maritimus The polar bear or the sea/ice bear are the world's largest land predators. They can be found in the Artic, the U.S.

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International Wolf Center | Teaching the World about Wolves.

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Wild Kids: A section all about wolves, just for kids

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There's so much to know about wolves - where they live, how they communicate, what they eat. Whether you study wolves, pretend to be a wolf or watch wolf movies, there are many different ways to learn about them. Let's learn more about wolves together!

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Mammals Mammals are a group of vertebrate animals. Mammals are characterized by their hair or fur. All mammals are are warm-blooded and they feed their young with milk (from special mammary glands). Check out some of the mammals with interesting facts about them.

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For such a big animal, polar bears sure start out small! A cub is about the size of a stick of butter when it is born. It is born hairless, with its eyes closed. Milk from polar bear mothers is 35 percent fat; this helps the cubs grow quickly.

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In Animal Upbringings, you'll learn what it's like to grow up in different animal families. Join Dr. Zoolittle and Roberta the Zebra on their journey as they explore how each animal family brings up their young in their very unique way. Host Michelle goes to the Oakland Zoo to visit a gray wolf family whose pups are on the move, getting into all sorts of mischief. You'll also visit the San Diego Zoo to meet a brand new Angolan colobus baby and see how it takes a troop to raise a baby. This episode is loaded with fun things including a trivia game, a craft, an egg-speriment, and a magic trick. Plus, you'll hear from viewers like you, who wrote in with their stories, jokes, and even a poem!

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Kids Corner Episode 5: Animal Upbringings

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In Animal Upbringings, you'll learn what it's like to grow up in different animal families. Join Dr. Zoolittle and Roberta the Zebra on their journey as they explore how each animal family brings up their young in their very unique way.

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Polar bears live along shores and on sea ice in the icy cold Arctic. When sea ice forms over the ocean in cold weather, many polar bears, except pregnant females, head out onto the ice to hunt seals.

Polar bears primarily eat seals. Polar bears often rest silently at a seal's breathing hole in the ice, waiting for a seal in the water to surface. A polar bear may also hunt by swimming beneath the ice. But climate change is making it harder for polar bears to hunt. Ice melts earlier and re-forms later than it has in the past. Without the sea ice, the polar bear must scavenge for other, less nutritious food.

Polar bears roam the Arctic ice sheets and swim in that region's coastal waters. They are very strong swimmers, and their large front paws, which they use to paddle, are slightly webbed. Some polar bears have been seen swimming hundreds of miles from land-though they probably cover most of that distance by floating on sheets of ice.

In fall pregnant polar bears make dens in earth and snowbanks, where they'll stay through the winter and give birth to one to three cubs. In spring the mother emerges from her den followed by her cubs. During that time she will protect them and teach them how to hunt. The U.S., Canada, Denmark, Norway, and Russia signed an agreement in 1973 to protect polar bears.

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Polar bears live along shores and on sea ice in the icy cold Arctic. When sea ice forms over the ocean in cold weather, many polar bears, except pregnant females, head out onto the ice to hunt seals. Polar bears primarily eat seals.

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Wolves live in groups called packs. A pack is a family of 7-8 wolves with a mom, dad, and offspring. The wolves’ communication skills are very important to the pack’s survival. Wolves work together to hunt, raise their young, and protect their territory. Wolves communicate with more than howls. They…

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NOVA scienceNOW | How Smart Are Dolphins? | Season 5 | Episode 4 | PBS

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These brainy marine mammals can "read," plan ahead, and communicate in astounding ways.

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Find out how dolphins “speak” to each other.

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NOVA scienceNOW | How Smart Are Dolphins? | Season 5 | Episode 4 | PBS

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These brainy marine mammals can "read," plan ahead, and communicate in astounding ways.

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Find out how dolphins “speak” to each other.

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Find amazing facts about animals, science, history and geography, along with fun competitions, games and more. Visit National Geographic Kids today!

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THE BIGGER THE BETTER

Asian elephants live in the tropical forests and grasslands of Southeast Asia. They're a little smaller than African elephants but can grow nine feet tall and weigh nearly six tons. That's heavier than two medium-size cars! Even newborns are on the hefty side, weighing some 200 pounds. Given their size it's no surprise that these guys are big on food. Adults can eat 300 pounds in one day, nearly 75 times what the average human eats! An Asian elephant's ideal meal includes roots, grasses, fruit, and bark.

Much of an Asian elephant's time is spent searching for grub. In fact the animal may travel 50 miles a day to find food. Asian elephants also enjoy taking dips in the water. To cool down their backsides, the animals will fill their trunks with water and spray it over themselves like a hose.

SOCIAL NETWORK

Asian elephants are gentle and super-social. Related females live with their young in herds. (Adult males go off on their own.) To communicate with each other they use rumbles, bellows, growls, and moans. Some of their vocalizations can be heard more than a mile away. Talk about a long-distance call!

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A three-foot-deep watering hole in northeast India hums with buzzing insects and chirping birds. Suddenly seven Asian elephants stomp through the grass surrounding the pool and splash into the water. It's bath time for the herd. THE BIGGER THE BETTER Asian elephants live in the tropical forests and grasslands of Southeast Asia.

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Explore National Geographic. A world leader in geography, cartography and exploration.

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Cetaceanhabitat.org focuses on the habitat needs of whales, dolphins and porpoises and the creation and management of marine protected areas for cetaceans; it contains a directory of all MPAs and sanctuaries worldwide that feature or include cetacean habitat. The site also contains the latest news on campaigns, proposals and developments relating to marine habitat conservation.

Follow the links below for more information on:

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Cetacean Habitat - Marine Protected Areas

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Cetaceanhabitat.org focuses on the habitat needs of whales, dolphins and porpoises and the creation and management of marine protected areas for cetaceans; it contains a directory of all MPAs and sanctuaries worldwide that feature or include cetacean habitat. The site also contains the latest news on campaigns, proposals and developments relating to marine habitat conservation.

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When an elephant drinks, it sucks as much as 2 gallons (7.5 liters) of water into its trunk at a time. Then it curls its trunk under, sticks the tip of its trunk into its mouth, and blows. Out comes the water, right down the elephant's throat.

Since African elephants live where the sun is usually blazing hot, they use their trunks to help them keep cool. First they squirt a trunkful of cool water over their bodies. Then they often follow that with a sprinkling of dust to create a protective layer of dirt on their skin. Elephants pick up and spray dust the same way they do water-with their trunks.

Elephants also use their trunks as snorkels when they wade in deep water. An elephant's trunk is controlled by many muscles. Two fingerlike parts on the tip of the trunk allow the elephant to perform delicate maneuvers such as picking a berry from the ground or plucking a single leaf off a tree. Elephants can also use its trunk to grasp an entire tree branch and pull it down to its mouth and to yank up clumps of grasses and shove the greenery into their mouths.

When an elephant gets a whiff of something interesting, it sniffs the air with its trunk raised up like a submarine periscope. If threatened, an elephant will also use its trunk to make loud trumpeting noises as a warning.

Elephants are social creatures. They sometimes hug by wrapping their trunks together in displays of greeting and affection. Elephants also use their trunks to help lift or nudge an elephant calf over an obstacle, to rescue a fellow elephant stuck in mud, or to gently raise a newborn elephant to its feet. And just as a human baby sucks its thumb, an elephant calf often sucks its trunk for comfort. One elephant can eat 300 pounds (136 kilograms) of food in one day.

People hunt elephants mainly for their ivory tusks. Adult females and young travel in herds, while adult males generally travel alone or in groups of their own.

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When an elephant drinks, it sucks as much as 2 gallons (7.5 liters) of water into its trunk at a time. Then it curls its trunk under, sticks the tip of its trunk into its mouth, and blows. Out comes the water, right down the elephant's throat.

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Leopard sharks inhabit a narrow band of ocean and inlet areas in the Pacific Ocean between Oregon and the Gulf of Mexico. They are some of the most common sharks found along the coast of California. These sharks have dark, saddle-shaped splotches along the fins and upper body.

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Dolphins are aquatic mammals which live in most seas around the world. Like most mammals they are viviparous and breathe through their lungs. They are also very intelligent animals. Come meet this inc

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At first glance, African elephants look similar to Asian elephants, but they are different species that live in different parts of the world. Here are some helpful clues for telling the 2 species apart: African elephants have very large ears that are shaped like the continent of Africa, while Asian elephants have smaller ears.

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Are you in search or cool fun facts about our world, space, bugs, animals, dinosaurs, and much more? Then look no further! Here's a fun and exciting new series about some of the best topics ever! Learn basic facts, discover things you didn't know and find out the answers to your burning questions.

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Dolphin Facts
This is an easy to understand video about dolphins. They are highly intelligent and curious mammals. They are found globally, mostly in shallow seas of the continental shelves and are carnivores. They mostly eat fish and squid.
How many teeth do they have?
Some dolphins have 8 teeth and some are found with 250. Bottlenose dolphins have 72-104 teeth (approx.). They only get one set of teeth for their whole life. They do not use their teeth to chew their food. They only catch their food with the help of teeth and then swallow it whole at once.
Do they drink water?
No, they do not because they live in saltwater. They get their required amount of water from the fishes they eat. They choose the type of fish they are going to eat depending on the amount of calories and water they need.
Can they see Colors?
They can see colors in the shade of grey and blue-green spectrum.
Can they see above the water?
Yes they can. When they use their vision to look at objects under the water, they produce an oily substance which forms a layer of protection. They can also see very well at night like cats and dogs.
Do they have hair?
They are mammals so they must have hair. But they only have hair at the time of their birth. This hair is found on the top of the rostrum and falls out within two weeks.
Are Dolphins fish?
No, they are mammals.
Name the smallest dolphin.
In terms of length, New Zealand Dolphin and Vaquita are smallest and in terms of weight, Finless Porpoise is the lightest.
How do they sleep?
They only let one half of their brain sleep at time. They have to be conscious to continue breathing. If they went into a deep sleep, they would stop breathing.

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Learn something new by watching our fun Dolphin facts for kids video! Kids will enjoy learning about dolphins and other topics with our fun science videos!

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Meet the elephant, an endangered animal found throughout Africa and Asia that’s big on brainpower, big on appetite, and just plain BIG!

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Explore National Geographic. A world leader in geography, cartography and exploration.

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Our Mission - Through education, research and rescue, Dolphin Research Center promotes peaceful coexistence, cooperation and communication between marine mammals, humans and the environment we share with the well being of DRC's animals taking precedence.

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Kids Dolphin Facts - Dolphin Research Center

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Kids can learn about dolphins, sea lions, and marine mammals. Dolphin camp, riddles, puzzles and dolphin facts.

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Explore National Geographic. A world leader in geography, cartography and exploration.

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Watch for free your favorite PBS KIDS shows like Daniel Tiger's Neighborhood, Wild Kratts, Odd Squad, and Sesame Street.

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Explore National Geographic. A world leader in geography, cartography and exploration.

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Explore National Geographic. A world leader in geography, cartography and exploration.

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Sharks are a superorder of fish called the Selachimorpha. They, like other Chondrichthyes, have skeletons made of cartilage instead of bone. Cartilage is tough, rubbery material which is less rigid than bone. Cartilaginous fish also include skates and rays.

There are more than 350 different kinds of sharks, such as the great white and whale sharks. Fossils show that sharks have been around for 420 million years, since the early Silurian.

Most sharks are predators, meaning they hunt and eat fish, marine mammals, and other sea creatures. However, the largest shark eats krill, like whales. This is the whale shark, the largest fish in the world. Some common kinds of shark include the hammerhead shark, the great white shark, the tiger shark, and the mako shark.

Characteristics

Sharks come in many different shapes and sizes, but most are long and thin (also called streamlined), with powerful jaws. Their teeth are constantly replaced throughout their lives. Sharks eat so violently they often break a few teeth, so new teeth grow continuously in a groove just inside the mouth and move forward from inside the mouth on "conveyor belts" formed by the skin in which they are attached to. In its lifetime, a shark can lose and regrow as many as 30,000 teeth.

Even with all those teeth, though, sharks can not chew. So they bite their prey and jerk it around so they can pull of a chunk to swallow. The chunks of food that a shark swallows ends up in its stomach, where they are digested. This is pretty slow, however, so a meal might take several days to digest. This is why a shark does not eat every day.

Sharks have different-shaped teeth, depending on what they eat. For instance, some sharks have sharp, pointy teeth, while bottom dwelling sharks have cone-shaped teeth for crushing shells. Because there are so many different kinds of sharks, and because each kind has its own kind of special teeth, many people enjoy collecting shark teeth. Shark teeth collectors can guess how large a shark was by measuring the shark tooth! First, they measure the length of the tooth in inches. Every inch of tooth equals 10ft of shark length: so if a shark tooth is 2 inches long, the tooth came from a shark that was 20 ft long! Even more terrifying is that some of the teeth are 6 inches long so that suggets a shark 60 feet long.

Sharks have skin covered in millions of tiny teeth-like scales that point to the tail. If you rub along a shark towards the tail, it would feel smooth, but if you rub the other way, it would be rough. Sharks' teeth can be 20 times as big as human teeth and they can grow back if they are lost.

The fins of sharks are used for stabilizing, steering, lift and swimming. Each fin is used in a different manner.

There are one or two fins present along the dorsal midline called the first and second dorsal fin. These fins help the shark from constantly rolling around. These two fins may, or may not have spines. When spines are present, they are used for defensive purposes, and may also have skin glands with them that produce an irritating substance.

The pectoral fins are located behind the head and extend outwards. These fins are used for steering during swimming and help to provide the shark with lift.

The pelvic fins are located behind the pectoral fins, near the claoca, and are also stabilizers.

Not all sharks have anal fins, but if they do have them, they are found between the pelvic and caudal fins.

The tail region itself consists of the caudal peduncle and the caudal fin. The caudal peduncle sometimes has notches known as "precaudal pits", which are found just ahead of the caudal fin. The peduncle may also be horizontally flattened into lateral keels. The caudal fin has both, an upper lobe, and a lower lobe, that can be of different sizes and the shape depends of which species the shark is. The primary use of the caudal fin is to provide a "push" while the shark swims. The upper lobe of the caudal fin produces the most amount of the push, and usually forces the shark downwards. The pectoral fins and the shape of the body (like an airfoil) work together to counter this force. The strong, non-lunate caudal fin in most benthic shark species allows the shark to swim close to the seabed (such as the Nurse shark). However, the fastest swimming sharks (such as the Mako sharks) tend to have lunate-shaped (crescent-shaped) caudal fins.

Sharks have keen olfactory sense organs in the short duct between the front and back nasal openings. They can detect blood from miles away: as little as one part per million of blood in sea water may be enough.

Sharks have the ability to determine the direction of a given scent based on the timing of scent detection in each nostril. This is similar to the method mammals use to determine direction of sound.

They are more attracted to the chemicals found in the intestines of many species, and as a result often linger near or in sewage outfalls. Some species, such as nurse sharks, have external barbels that greatly increase their ability to sense prey.

Shark eyes are similar to the eyes of other vertebrates, including similar lenses, corneas and retinas. Their eyesight is well adapted to the marine environment. They can contract and dilate their pupils, like humans, something no teleost fish can do. A tissue behind the retina reflects light back, thereby increasing sight in darker waters.

Sensing electric current

Sharks have tiny holes all over the shark's snout, especially between the eye and the tip of the snout. In them are which are nerve receptors called the ampullae of Lorenzini. p23 They can sense electricity in the water. Animal in the water give off electricity: every time an animal's heart beats or it moves, tiny currents of electricity are made. These tiny electric currents make signals that travel through water and get sensed. Sharks may use this sense when they catch their prey, even more than they use their sight.

Although it is hard to test sharks' hearing, they may have a sharp sense of hearing and can possibly hear prey many miles away. A small opening on each side of their heads (not the spiracle) leads directly into the inner ear through a thin channel.

Lateral line

The lateral line detects changes in water pressure. It is open to the environment by a line of pores. This and the sound-detecting organs are grouped together as the 'acoustico-lateralis system', because they have a common origin. In bony fish and tetrapods the external opening into the inner ear has been lost.

This system is found in other fish as well. It detects motion or vibrations in water. The shark can sense frequencies in the range of 25 to 50 Hz.

Prehistoric sharks

Because sharks have skeletons made of cartilage, they do not fossilize easily. That's because cartilage is softer than bone and falls apart before fossilizing. However, teeth are harder, and if that is not enough, they are shed throughout a shark's lifetime. Therefore, shark teeth are one of the most common fossils.

Sharks existed for at least two hundred million years before the dinosaurs. The earliest shark fossils were scales, so could it be that the earliest sharks were toothless? We are not sure. Early sharks did not look like sharks of today. For example, the upper snout of modern sharks is longer than the lower jaw. But in early sharks, they were the same length.

The first modern-looking sharks appeared in the Age of Dinosaurs. Sharks back then were preyed on by giant sea reptiles.

Just a few million years ago, a giant shark called swam in the seas. It was 18 meters long, twice as long as the closely-related great white shark, and it ate whales. Megalodon died out 1.6 million years ago.

Reproduction

About 70% of all known shark species give birth to live young, with the gestation period lasting from 6 to 22 months.

Pups are born with a full set of teeth, and are capable of taking care of themselves. Once born, they quickly swim away from their mothers, who sometimes feed on the pups. Litters vary from one or two pups ( Great white shark) to one hundred pups ( Blue shark and Whale shark).

Some sharks are oviparous, laying their eggs in the water. Shark eggs (sometimes called "mermaid's purses") are covered by a tough, leathery membrane. The egg has a yolk that feeds the embryo, very much like a chicken egg.

Ovoviviparity

Most sharks are ovoviviparous, meaning the eggs hatch inside the female's body, with the babies developing within the mother, but there is no placenta to nourish the pups. Instead the young feed on the egg's yolk. The pups eat any unfertilized eggs and sometimes each other. Very few pups in a litter survive until birth due to this form of sibling cannibalism. Great white sharks, Mako sharks, Nurse sharks, Tiger sharks, and Sand tiger sharks reproduce this way.

Viviparity

Some sharks are viviparous, meaning that the females give live birth: the eggs hatch inside the female's body, and the babies are fed by a placenta. The placenta helps transfer nutrients and oxygen from the mother's bloodstream and transfers waste products from the baby to the mother for elimination. Examples of viviparous sharks include the Bull sharks, the Whitetip reef sharks, the Lemon sharks, the Blue sharks, the Silvertip sharks, and the Hammerhead sharks. Although long thought to be oviparous, Whale sharks are viviparous, and pregnant females have been found containing hundreds of pups.

New shark discoveries

New sharks are still being found. Dave Ebert has found ten new species in a Taiwan market alone. Over the past three decades he has named 24 new species. They include sharks, rays, sawfish and ghost sharks - these cartilaginous fish are all related.

Some sharks are not endangered, but some are hunted for food (like shark fin soup) or sport fishing. In 2013 five species of shark, along with two species of manta ray, received international protection as part of the Convention on International Trade in Endangered Species.

It is estimated that 100 million sharks are killed by commercial and recreational fishing. Sharks are a common seafood in many places, including Japan and Australia.

In the Australian state of Victoria, shark is the most commonly used fish in fish and chips, in which fillets are battered and deep-fried or crumbed and grilled. In fish and chip shops, shark is called "flake".

In India, small sharks or baby sharks (called sora in Tamil language, Telugu language) are sold in local markets. Since the flesh is not developed, cooking the flesh breaks it into powder, which is then fried in oil and spices (called sora puttu/sora poratu). The soft bones can be easily chewed. They are considered a delicacy in coastal Tamil Nadu.

Related Pages

Images for kids

Fossil shark tooth (size over 9 cm or 3.5 inches) with crown, shoulder, root and root lobe

in}} egg case adjacent to ruler, the egg case is a brown ovalish shape, with a spiral band running around it from top to bottom.

Snorkeler swims near a blacktip reef shark. In rare circumstances involving poor visibility, blacktips may bite a human, mistaking it for prey. Under normal conditions they are harmless and shy.

In Spanish: Selachimorpha para niños

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Entertain yourself viewing from the really best unique and really easy to understand American Alligator Facts easy science for kids video:
Information about this American Alligator Facts Video

Watch this good video and you'll learn a lot of fun facts about the American alligator. With this video, you will be able to know what the scientific name for an American alligator is, how they are found in South East United States and how a lot of them are found in Florida. You will also be able to learn how there are only 2 species of alligator in the world and how the other one is found in China. The video will share more facts like how long they can get, how the largest alligator recorded was 19 feet 2 inches, and show a real live alligator to point out some of their fascinating features and body parts.

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American Alligator Facts Video for Kids -

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Easy Science for Kids American Alligator Facts Video for Kids - learn fun facts about animals, the human body, our planet and much more. Fun free American Alligator Facts Video for Kids activities!

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Learn how dolphins eat, sleep, and live together. Bottlenose dolphins and orcas travel the ocean in pods.

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Although they are sometimes shown in movies as being mean or scary, gorillas are very gentle animals. They live in groups called troops that contain a silverback, many females, and offspring. The troop travels around the forest together looking for food during the day.

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We’ve been digging and digging, but we can’t find that page anywhere in our burrows.

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When a great white shark is born, along with up to a dozen siblings, it immediately swims away from its mother. Born on the east and west coasts of North America, the south of Africa and southwest Australia, baby sharks are on their own right from the start. Their mother may see them only as prey.

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When a great white shark is born, along with up to a dozen siblings, it immediately swims away from its mother. Born on the east and west coasts of North America, the south of Africa and southwest Australia, baby sharks are on their own right from the start.

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Physical Description

The critically endangered Chinese alligator differs from its American counterpart in subtle ways. It's smaller, the head is more robust and its snout is slightly upturned. The eyelids of the Chinese alligator have a bony plate that is missing in the American alligator. The American alligator also lacks the bony belly plates, or osteoderms, of the Chinese alligator.

Chinese alligators usually grow to about 5 feet (1.5 meters). The largest Chinese alligator measured in recent times was 7 feet and 1 inch--about half the size of the largest living American alligators. Some may weigh up to 85 pounds (38.5 kilograms); however, most weigh less than 50 pounds (23 kilograms).

Native Habitat

The Chinese alligator is the only member of the eight species in the Alligatoridae family to exist outside of the Americas. In historical times, the Chinese alligator was found in the extensive lakes and marshlands of the middle-lower Yangtze River region and along the river from Shanghai to Jianling City in the Hubei Province. Today it is limited to the lower Yangtze, primarily in the Anhui and Zhejiang provinces in eastern China.

Chinese alligators are found in slow-moving freshwater rivers and streams, including lakes, ponds and swamps. Marshlands, ponds, lakes, reservoirs, river backwater canals, rice paddies and irrigation networks provide suitable habitat.

Communication

Young vocalize to bring the group together and maintain its cohesion, while adults respond to juvenile distress calls. Bellowing occurs among males and females during the breeding season.

Food/Eating Habits

The Chinese alligator is an opportunistic feeder. Its diet mostly includes snails, crustaceans, insects and fish, but young waterfowl and rodents will be taken if available. Dentition includes blunt teeth adapted well to crushing shelled animals.

At the Smithsonian's National Zoo, Chinese alligators are fed small rats, mice and fish.

Reproduction and Development

The mating system is polygamous, as a male may breed with more than one female. Both sexes may react very aggressively to one another, especially in first encounter situations. Social life begins before hatching, as nest mates communicate egg to egg and with parents who open the egg chamber when synchronized hatching begins. Nest mates may spend weeks to years together in the protection of the mother.

Females mature at about four to five years. Mating occurs in early summer, with the females building nests about two to three weeks later and laying up to four-dozen eggs; fewer than two-dozen is common. Hatchlings generally emerge in September. Females provide parental care, including assisting the hatching process and carrying the newly hatched young from the nests, which are located on land, to the water.

Sleep Habits

This species digs extensive earthen tunnels with multiple chambers, entrances and pools. Largely nocturnal because of human persecution, they stay in their tunnels much of the day when humans are in the vicinity as well as during cool weather and winter months.

Each year in April, the alligators emerge from their winter burrows and find sunny spots in which to bask. As summer begins, they switch to more nocturnal feeding habits to avoid the heat and humans while they begin their annual mating rituals.

Chinese alligators can live up to 70 years in human care. They can reproduce into their 50s.

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The critically endangered Chinese alligator is one of the few alligators outside of the Americas. It is native to slow-moving, freshwater areas of the lower Yangtze River in China where it eats snails, crustaceans, insects, fish, young waterfowl and rodents.

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Thought to be some of the smartest animals on Earth, bottlenose dolphins send messages to one another in many different ways. They squeak, squawk and use body language—leaping as high as 20 feet in the air, snapping their jaws, slapping their tails on the surface of the water, blowing bubbles and ev…

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Watch to discover interesting facts about animals from all over the world.

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Watch to discover interesting facts about animals from all over the world.

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Explore National Geographic. A world leader in geography, cartography and exploration.

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The 8 Main Differences Between Alligators and Crocodiles

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Many people struggle to tell these two reptiles apart, but it isn't that difficult when you know what to look for. What is the difference between alligators and crocodiles? Well, there are essentially 8 main ways to tell them apart...

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Learn how dolphins eat, sleep, and live together. Bottlenose dolphins and orcas travel the ocean in pods.

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Elephant facts

1) There are threedifferent species of elephant - the African Savannah elephant, the African Forest elephant and the Asian elephant. Elephants are known for their large ears, tusks made of ivory and their trunks.

2) Elephants are the world's largest land animal! Male African elephants can reach 3m tall and weigh between 4,000 -7,500kg. Asian elephants are slightly smaller, reaching 2.7m tall and weighing 3,000- 6,000kg.

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3) There's an easy way to tell the African elephants apart from their Asian cousins - their ears! African elephants have large ears shaped like the continent of Africa! Asian elephants' ears are smaller and shaped like India. Cool, huh?

4) You can tell a lot about an elephant by looking at their tusks! Elephant tusks never stop growing, so enormous tusks can be a sign of an old elephant. Both male and female African elephants grow tusks, but only male Asian elephants grow them. A tusk-less adult elephant is likely to be a female Asian elephant.

5) Until recently, African Forest elephants were thought to be a subspecies of the African elephant, but new research discovered that they are actually a separate species entirely. These elephants live in the tropical forests of Africa's Congo Basin. They have straighter tusks and more rounded ears than Savannah elephants.

6) These magnificent mammals spend between 12 to 18 hours eating grass, plants and fruit every single day! They use their long trunks to smell their food and lift it up into their mouth - yum!

7) All that eating means one thing, gang, an awful lot of poo! Each elephant creates about one tonne of poo per week, which keeps the soil fertile and disperses tree seeds. Elephants also dig waterholes and create footpaths, literally changing the landscape around them!

8) In Mount Elgon National Park in , a group of elephants use their tusks to mine for salt in underground caves! They feel their way around with their trunks and eat the salts by breaking them off with their tusks.

9) Elephants have created their very own sunscreen! After a river or swamp bath, they'll throw mud and sand up and over themselves to protect their skin from the hot, burning sun. Clever!

10) Sadly, elephants are in trouble. Many are killed by humans for their ivory tusks, because they've come into conflict with communities or simply for sport. There are far fewer Asian elephants than there are African elephants. Asian elephants also face threats from tourist attractions where people pay to ride on their backs or watch them paint pictures using their trunks.

Check out more articles about awesome elephants! Read our interview with Harry Potter star Evanna Lynch to find out how she's helping elephants, and learn how one young boy is taking action to save these incredible animals.

What did you think of our elephant facts? Let us know by leaving a comment, below!

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Elephant facts | Animals | National Geographic Kids

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Discover awesome elephant facts with Nat Geo Kids. You'll discover different elephant species, learn where they live and more...

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Sharks & Rays

Sharks have played a vital role in maintaining healthy oceans for hundreds of millions of years as a top predator. More than 450 species of sharks cruise the world's oceans, ranging in size from 8 inches to a whopping 40 feet long. But today, nearly one in four sharks and their relatives are threatened with extinction. A major cause is the demand for shark fins. Every year, fins from as many as 73 million sharks end up in the global fin trade.

Learn fun facts and how you can help your favorite sharks - from great white sharks to hammerhead sharks - by clicking a species below.

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Sharks & Rays Sharks have played a vital role in maintaining healthy oceans for hundreds of millions of years as a top predator. More than 450 species of sharks cruise the world's oceans, ranging in size from 8 inches to a whopping 40 feet long.

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Only two species of these sneaky predators still cruise the rivers, lakes and swamps of the world.

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ReadWorks | Award-Winning, EdTech Nonprofit Organization

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ReadWorks is an edtech nonprofit organization that is committed to helping to solve America's reading comprehension crisis.

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Outdoor Nevada | Burrowing Owl | PBS LearningMedia

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In this video segment from Outdoor Nevada, listen as Brian Wignall describes the burrowing owl. Observe unique adaptive characteristics and behaviors that allow the only ground-dwelling owl to live and thrive over a wide area of western North and South America.

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Discover The Great White Shark Habitat Map | SEEtheWILD

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A simplified map that helps you learn about the Great White Shark Habitat across all the oceans, including prime breeding grounds.

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National Geographic | Disney Australia & New Zealand - Disney Australia

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National Geographic invites you to live curious through movies that will inspire you to find out more about the people, places and events of our world.

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Bottle Nose Dolphin

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Watch to discover interesting facts about animals from all over the world.

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Gorilla Facts - Silverback, Mountain, Zoo, Food, Habitat, Africa, Endangered, Info

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ReadWorks | Award-Winning, EdTech Nonprofit Organization

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ReadWorks is an edtech nonprofit organization that is committed to helping to solve America's reading comprehension crisis.

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The great horned owl gets its name from the tufts of feathers on its head that look like ears. But the owl's ears are really farther down on the side of its head, and are just openings in the skull hidden beneath feathers.

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The largest Shark known right now!

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Newsela is an Instructional Content Platform that supercharges reading engagement and learning in every subject.

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Explore our wide variety of animal facts and learn some fun trivia about our friends in the animal kingdom.

Fun Alligator Facts for Kids

Check out our range of fun alligator facts for kids. Learn about alligator's powerful bite, how much they weigh, what they eat and much more. Read on and enjoy a variety of interesting information about alligators.

Alligators are reptiles.

Alligators have been living on Earth for millions of years and are sometimes described as 'living fossils'.

There are two different species of alligator, the American alligator and the Chinese alligator.

American alligators live in south-eastern areas of the United States such as Florida and Louisiana.

Chinese alligators are found in the Yangtze River but they are critically endangered and only a few remain in the wild.

Like other reptiles, alligators are cold-blooded.

Alligators can weigh over 450 kg (1000 lb).

Alligators have a powerful bite but the muscles that open the jaw are relatively weak. An adult human could hold the jaws of an alligator shut with their bare hands.

Alligators eat a range of different animals such as fish, birds, turtles and even deer.

Alligator eggs become male or female depending on the temperature, male in warmer temperatures and female in cooler temperatures.

Alligators are less likely to attack humans than crocodiles.

Like crocodiles, alligators are part of the order 'Crocodylia'.

Check out some interesting alligator and crocodile differences.

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Fun Alligator Facts for Kids - Interesting Information about Alligators

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Explore our wide variety of animal facts and learn some fun trivia about our friends in the animal kingdom. Fun Alligator Facts for Kids Check out our range of fun alligator facts for kids. Learn about alligator's powerful bite, how much they weigh, what they eat and much more.

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For a long time the image most people had of a gorilla encounter included chest pounding, roaring, charging, and big, bared teeth. But researchers studying gorillas reveal a very different picture of mountain gorillas. The animals are peaceful, gentle, social, and mainly vegetarian creatures. The occasional ferocious-looking, impressive displays are generally from a male gorilla protecting his family group from a threat.

A typical group is led by the biggest and strongest mature male gorilla-often the guy doing any chest pounding or charging. He's called a silverback because the hair on a male's back turns from black to silvery gray as he matures. This happens when he is between 11 and 13 years old. A silverback's group normally includes a subadult male or two and a few females and their young. Mountain gorillas wander around a home range of up to 15 square miles (39 square kilometers).

Mountain gorillas spend much of their time eating. Their food includes a variety of plants, along with a few insects and worms. At night the animals make a nest to sleep in. Many lightweight gorillas nest in trees, making beds of bent branches. The heavier individuals may nest in grasses on the ground. Babies snuggle with their mothers for the night.

Life for mountain gorillas isn't all peaceful. They are endangered, threatened by civil war in a small area of Africa where they live. Hunters kill them for food or trophies. Their forests are chopped down for farmland, fuel, and housing. But many dedicated scientists, park rangers, and other concerned people are working hard to protect mountain gorillas, their forests, and their way of life in the mountains.

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Youngsters tumble, climb, and run playing follow the leader. Another group plays a rowdy game of king of the mountain. Several adults watch the action, relaxing nearby. Is this a playground scene at school? No, guess again. It's a lush mountain forest high in the Virunga mountains of Africa, and the playmates are young mountain gorillas under the watchful eyes of their mothers.

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When an elephant drinks, it sucks as much as 2 gallons (7.5 liters) of water into its trunk at a time. Then it curls its trunk under, sticks the tip of its trunk into its mouth, and blows. Out comes the water, right down the elephant's throat.

Since African elephants live where the sun is usually blazing hot, they use their trunks to help them keep cool. First they squirt a trunkful of cool water over their bodies. Then they often follow that with a sprinkling of dust to create a protective layer of dirt on their skin. Elephants pick up and spray dust the same way they do water-with their trunks.

Elephants also use their trunks as snorkels when they wade in deep water. An elephant's trunk is controlled by many muscles. Two fingerlike parts on the tip of the trunk allow the elephant to perform delicate maneuvers such as picking a berry from the ground or plucking a single leaf off a tree. Elephants can also use its trunk to grasp an entire tree branch and pull it down to its mouth and to yank up clumps of grasses and shove the greenery into their mouths.

When an elephant gets a whiff of something interesting, it sniffs the air with its trunk raised up like a submarine periscope. If threatened, an elephant will also use its trunk to make loud trumpeting noises as a warning.

Elephants are social creatures. They sometimes hug by wrapping their trunks together in displays of greeting and affection. Elephants also use their trunks to help lift or nudge an elephant calf over an obstacle, to rescue a fellow elephant stuck in mud, or to gently raise a newborn elephant to its feet. And just as a human baby sucks its thumb, an elephant calf often sucks its trunk for comfort. One elephant can eat 300 pounds (136 kilograms) of food in one day.

People hunt elephants mainly for their ivory tusks. Adult females and young travel in herds, while adult males generally travel alone or in groups of their own.

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When an elephant drinks, it sucks as much as 2 gallons (7.5 liters) of water into its trunk at a time. Then it curls its trunk under, sticks the tip of its trunk into its mouth, and blows. Out comes the water, right down the elephant's throat.

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Come learn cool and interesting facts about sharks in this educational video! Where do sharks live? What do sharks eat? How many different…

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Brought back from the brink of extinction, over a million of these reptiles survive today. Now the main threat to alligators is habitat destruction, caused by such human activities as draining and developing wetlands.

American alligators live in the wild in the southeastern United States. You're most likely to spot them in Florida and Louisiana, where they live in rivers, lakes, ponds, swamps, bayous, and marshes. These reptiles are kind of clumsy on land, but they're built for life in the water. Great swimmers, they are equipped with webbed feet and strong tails that propel them through the water.

An average male American alligator is 10 to 15 feet (three to five meters) long. Half of its length is its massive, strong tail. An alligator can weigh as much as half a ton (1,000 pounds), but an average male weighs between 500 and 600 pounds (227 to 272 kilograms). Females are usually smaller than males.

As big and ferocious as the female alligator may look, she is a gentle mother. A mother alligator makes a nest on shore, where she lays her eggs. Then she guards her eggs until they're ready to hatch. At that point the babies start to make noises, and their mother hears her little ones' peeps as they break out of the eggs. She gently carries them-in her mouth-to the water nearby.

Newly hatched young are only about six to eight inches (15 to 20 centimeters) long, and very vulnerable. Their mother protects them from predators, which include raccoons, bobcats, birds, and even other alligators. The young alligators stay with their mother for up to two years. After that, they're able to fend for themselves.

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American alligators once faced extinction. The United States Fish and Wildlife Service placed them on the endangered species list in 1967. Fortunately, the legal protection worked. Just 20 years later, American alligators were taken off the list. Brought back from the brink of extinction, over a million of these reptiles survive today.

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Dolphin Article and Videos

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a comprehensive suite of e-learning resources designed for all ages and abilities with articles

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A comprehensive suite of e-learning resources designed for all ages and abilities with articles, videos, educator tools, eBooks, research guides and more.

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Learn about the Gorilla, strong and intelligent African primate that is endangered.

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Elephants: Learn about the biggest land animal.

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Why do Elephants have big ears, trunks, tusks? Learn about elephants, the endangered giants of India and Africa

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This small bird, found in North and South America, is different from most other owls. While other owls are active only at night, a burrowing owl hunts during the day as well as at night. Instead of nesting in a hollow high up in a tree, it nests in an underground burrow.