Giant Panda

The giant panda has an insatiable appetite for bamboo. A typical animal eats half the day—a full 12 out of every 24 hours—and relieves itself dozens of times a day. It takes 28 pounds (12.5 kilograms) of bamboo to satisfy a giant panda's daily dietary needs, and it hungrily plucks the stalks with elongated wrist bones that function rather like thumbs. Pandas will sometimes eat birds or rodents as well.

Wild pandas live only in remote, mountainous regions in central China. These high bamboo forests are cool and wet—just as pandas like it. They may climb as high as 13,000 feet (3,962 meters) to feed on higher slopes in the summer season.

Pandas are often seen eating in a relaxed sitting posture, with their hind legs stretched out before them. They may appear sedentary, but they are skilled tree-climbers and efficient swimmers.

Giant pandas are solitary. They have a highly developed sense of smell that males use to avoid each other and to find females for mating in the spring. After a five-month pregnancy, females give birth to a cub or two, though they cannot care for both twins. The blind infants weigh only 5 ounces (142 grams) at birth and cannot crawl until they reach three months of age. They are born white, and develop their much loved coloring later.

There are only about 1,000 giant pandas left in the wild. Perhaps 100 pandas live in zoos, where they are always among the most popular attractions. Much of what we know about pandas comes from study of these zoo animals, because their wild cousins are so rare and elusive.

Jaguar

Jaguars are the largest of South America's big cats. They once roamed from the southern tip of that continent north to the region surrounding the U.S.-Mexico border. Today significant numbers of jaguars are found only in remote regions of South and Central America—particularly in the Amazon basin.

These beautiful and powerful beasts were prominent in ancient Native American cultures. In some traditions the Jaguar God of the Night was the formidable lord of the underworld. The name jaguar is derived from the Native American word yaguar, which means "he who kills with one leap."

Unlike many other cats, jaguars do not avoid water; in fact, they are quite good swimmers. Rivers provide prey in the form of fish, turtles, or caimans—small, alligatorlike animals. Jaguars also eat larger animals such as deer, peccaries, capybaras, and tapirs. They sometimes climb trees to prepare an ambush, killing their prey with one powerful bite.

Most jaguars are tan or orange with distinctive black spots, dubbed "rosettes" because they are shaped like roses. Some jaguars are so dark they appear to be spotless, though their markings can be seen on closer inspection.

Jaguars live alone and define territories of many square miles by marking with their waste or clawing trees.

Females have litters of one to four cubs, which are blind and helpless at birth. The mother stays with them and defends them fiercely from any animal that may approach—even their own father. Young jaguars learn to hunt by living with their mothers for two years or more.

Jaguars are still hunted for their attractive fur. Ranchers also kill them because the cats sometimes prey upon their livestock.

Polar Bear

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.

Polar bears live in one of the planet's coldest environments and depend on a thick coat of insulated fur, which covers a warming layer of fat. Fur even grows on the bottom of their paws, which protects against cold surfaces and provides a good grip on ice. The bear's stark white coat provides camouflage in surrounding snow and ice. But under their fur, polar bears have black skin—the better to soak in the sun's warming rays.

These powerful predators typically prey on seals. In search of this quarry they frequent areas of shifting, cracking ice where seals may surface to breathe air. They also stalk ice edges and breathing holes. If the opportunity presents itself, polar bears will also consume carcasses, such as those of dead whales. These Arctic giants are the masters of their environment and have no natural enemies.

Females den by digging into deep snow drifts, which provide protection and insulation from the Arctic elements. They give birth in winter, usually to twins. Young cubs live with their mothers for some 28 months to learn the survival skills of the far north. Females aggressively protect their young, but receive no help from their solitary male mates. In fact, male polar bears may even kill young of their species.

Polar bears are attractive and appealing, but they are powerful predators that do not typically fear humans, which can make them dangerous. Near human settlements, they often acquire a taste for garbage, bringing bears and humans into perilous proximity.

Peacock

Peacocks are large, colorful pheasants (typically blue and green) known for their iridescent tails. These tail feathers, or coverts, spread out in a distinctive train that is more than 60 percent of the bird’s total body length and boast colorful "eye" markings of blue, gold, red, and other hues. The large train is used in mating rituals and courtship displays. It can be arched into a magnificent fan that reaches across the bird's back and touches the ground on either side. Females are believed to choose their mates according to the size, color, and quality of these outrageous feather trains.

The term "peacock" is commonly used to refer to birds of both sexes. Technically, only males are peacocks. Females are peahens, and together, they are called peafowl.

Suitable males may gather harems of several females, each of which will lay three to five eggs. In fact, wild peafowl often roost in forest trees and gather in groups called parties.

Peacocks are ground-feeders that eat insects, plants, and small creatures. There are two familiar peacock species. The blue peacock lives in India and Sri Lanka, while the green peacock is found in Java and Myanmar (Burma). A more distinct and little-known species, the Congo peacock, inhabits African rain forests.

Peafowl such as the blue peacock have been admired by humans and kept as pets for thousands of years. Selective breeding has created some unusual color combinations, but wild birds are themselves bursting with vibrant hues. They can be testy and do not mix well with other domestic birds.

Great White Shark

The legendary great white shark is far more fearsome in our imaginations than in reality. As scientific research on these elusive predators increases, their image as mindless killing machines is beginning to fade.

Of the 100-plus annual shark attacks worldwide, fully one-third to one-half are attributable to great whites. However, most of these are not fatal, and new research finds that great whites, who are naturally curious, are "sample biting" then releasing their victims rather than preying on humans. It's not a terribly comforting distinction, but it does indicate that humans are not actually on the great white's menu.

Great whites are the largest predatory fish on Earth. They grow to an average of 15 feet (4.6 meters) in length, though specimens exceeding 20 feet (6 meters) and weighing up to 5,000 pounds (2,268 kilograms) have been recorded.

They have slate-gray upper bodies to blend in with the rocky coastal sea floor, but get their name from their universally white underbellies. They are streamlined, torpedo-shaped swimmers with powerful tails that can propel them through the water at speeds of up to 15 miles (24 kilometers) per hour. They can even leave the water completely, breaching like whales when attacking prey from underneath.

Highly adapted predators, their mouths are lined with up to 300 serrated, triangular teeth arranged in several rows, and they have an exceptional sense of smell to detect prey. They even have organs that can sense the tiny electromagnetic fields generated by animals. Their main prey items include sea lions, seals, small toothed whales, and even sea turtles, and carrion.

Found in cool, coastal waters throughout the world, there is no reliable data on the great white's population. However, scientists agree that their number are decreasing precipitously due to overfishing and accidental catching in gill nets, among other factors, and they are listed as an endangered species.

Green Sea Turtle

The green turtle is a large, weighty sea turtle with a wide, smooth carapace, or shell. It inhabits tropical and subtropical coastal waters around the world and has been observed clambering onto land to sunbathe.

It is named not for the color of its shell, which is normally brown or olive depending on its habitat, but for the greenish color of its skin. There are two types of green turtles—scientists are currently debating whether they are subspecies or separate species—including the Atlantic green turtle, normally found off the shores of Europe and North America, and the Eastern Pacific green turtle, which has been found in coastal waters from Alaska to Chile.

Weighing up to 700 pounds (317.5 kilograms) green turtles are among the largest sea turtles in the world. Their proportionally small head, which is nonretractable, extends from a heart-shaped carapace that measures up to 5 feet (1.5 meters). Males are slightly larger than females and have a longer tail. Both have flippers that resemble paddles, which make them powerful and graceful swimmers.

Unlike most sea turtles, adult green turtles are herbivorous, feeding on sea grasses and algae. Juvenile green turtles, however, will also eat invertebrates like crabs, jellyfish, and sponges.

While most sea turtles warm themselves by swimming close to the surface of shallow waters, the Eastern Pacific green turtle will take to land to bask in the sun. Occasionally seen sunbathing alongside seals and albatrosses, it is one of the few marine turtles known to leave the water other than at nesting times.

Green turtles, like other sea turtles, undertake lengthy migrations from feeding sites to nesting grounds, normally on sandy beaches. Mating occurs every two to four years and normally takes place in shallow waters close to the shore. To nest, females leave the sea and choose an area, often on the same beach used by their mothers, to lay their eggs. They dig a pit in the sand with their flippers, fill it with a clutch of 100 to 200 eggs, cover the pit and return to the sea, leaving the eggs to hatch after about two months. The most dangerous time of a green turtle’s life is when it makes the journey from nest to sea. Multiple predators, including crabs and flocks of gulls, voraciously prey on hatchlings during this short scamper.

Green turtles are listed as an endangered species, and a subpopulation in the Mediterranean is listed as critically endangered. Despite this, they are still killed for their meat and eggs. Their numbers are also reduced by boat propeller accidents, fishnet-caused drowning, and the destruction of their nesting grounds by human encroachment.

Koala

Though often called the koala "bear," this cuddly animal is not a bear at all; it is a marsupial, or pouched mammal. After giving birth, a female koala carries her baby in her pouch for about six months. When the infant emerges, it rides on its mother's back or clings to her belly, accompanying her everywhere until it is about a year old.

Koalas live in eastern Australia, where the eucalyptus trees they love are most plentiful. In fact, they rarely leave these trees, and their sharp claws and opposable digits easily keep them aloft. During the day they doze, tucked into forks or nooks in the trees, sleeping for up to 18 hours.

When not asleep a koala feeds on eucalyptus leaves, especially at night. Koalas do not drink much water and they get most of their moisture from these leaves. Each animal eats a tremendous amount for its size—about two and a half pounds (one kilogram) of leaves a day. Koalas even store snacks of leaves in pouches in their cheeks.

A special digestive system—a long gut—allows koalas to break down the tough eucalyptus leaves and remain unharmed by their poison. Koalas eat so many of these leaves that they take on a distinctive odor from their oil, reminiscent of cough drops.

These plump, fuzzy mammals were widely hunted during the 1920s and 1930s, and their populations plunged. Helped by reintroduction, they have reappeared over much of their former range, but their populations are smaller and scattered. Koalas need a lot of space—about a hundred trees per animal—a pressing problem as Australia's woodlands continue to shrink.

Eastern Gray Kangaroo

Gray kangaroos roam the forests of Australia and Tasmania and prefer to live among the trees, though they do take to open grasslands for grazing.

Gray kangaroos, red kangaroos, and wallaroos are called the great kangaroos because they are so much larger than the nearly 70 other kinds of kangaroos.

Gray kangaroos hop along on their powerful hind legs and do so at great speed. A gray kangaroo can reach speeds of over 35 miles (56 kilometers) an hour and travel for long distances at 15 miles (24 kilometers) an hour. Their bounding gate allows them to cover 25 feet (8 meters) in a single leap and to jump 6 feet (1.8 meters) high.

Females have one baby at a time, which at birth is smaller than a cherry. The infant immediately climbs into its mother's pouch and does not emerge for two months. Until they reach about 10 or 11 months of age, threatened young kangaroos, called joeys, will quickly dive for the safety of mom's pouch. As they grow, joeys' heads and feet can often be seen hanging out of the pouch.

Larger male kangaroos are powerfully built. Like many species, male kangaroos sometimes fight over potential mates. They often lean back on their sturdy tail and "box" each other with their strong hind legs. Kangaroos can also bite and wield sharp claws, which they may do in battle with an enemy, such as a dingo.

Gray kangaroos gather in groups called "mobs." Aboriginal and European Australians have spent centuries clearing open tracts of land and establishing water sources—both of which are boons to kangaroo populations. Many millions of these animals roam Australia, and considerable numbers are killed each year for their skins and meat, which is becoming a more popular human food.

Giraffe

Giraffes are the world's tallest mammals, thanks to their towering legs and long necks. A giraffe's legs alone are taller than many humans—about 6 feet (1.8 meters). These long legs allow giraffes to run as fast as 35 miles (56 kilometers) an hour over short distances and cruise comfortably at 10 miles (16 kilometers) an hour over longer distances.

Typically, these fascinating animals roam the open grasslands in small groups of about half a dozen.

Bulls sometimes battle one another by butting their long necks and heads. Such contests aren't usually dangerous and end when one animal submits and walks away.

Giraffes use their height to good advantage and browse on leaves and buds in treetops that few other animals can reach (acacias are a favorite). Even the giraffe's tongue is long! The 21-inch (53-centimeter) tongue helps them pluck tasty morsels from branches. Giraffes eat most of the time and, like cows, regurgitate food and chew it as cud. A giraffe eats hundreds of pounds of leaves each week and must travel miles to find enough food.

The giraffe's height also helps it to keep a sharp lookout for predators across the wide expanse of the African savanna.

The giraffe's stature can be a disadvantage as well—it is difficult and dangerous for a giraffe to drink at a water hole. To do so they must spread their legs and bend down in an awkward position that makes them vulnerable to predators like Africa's big cats. Giraffes only need to drink once every several days; they get most of their water from the luscious plants they eat.

Female giraffes give birth standing up. Their young endure a rather rude welcome into the world by falling more than 5 feet (1.5 meters) to the ground at birth. These infants can stand in half an hour and run with their mothers an incredible ten hours after birth.

Giraffes have beautiful spotted coats. While no two individuals have exactly the same pattern, giraffes from the same area appear similar.

Green Basilisk Lizard

The green basilisk lizard is also called a plumed or double-crested basilisk; but its amazing ability to run on water gives this species its most recognizable moniker: the Jesus Christ lizard.

Abundant in the tropical rain forests of Central America, from southern Mexico to Panama, green basilisks spend much of their time in the trees and are never far from a body of water. When threatened, they can drop from a tree into the water and sprint, upright, about 5 feet (1.5 meters) per second across the surface.

To accomplish this, they have long toes on their rear feet with fringes of skin that unfurl in the water, increasing surface area. As they rapidly churn their legs, they slap their splayed feet hard against the water, creating a tiny air pocket that keeps them from sinking, provided they maintain their speed. They can move along the surface like this for 15 feet (4.5 meters) or more. When gravity eventually does take over, the basilisk resorts to its excellent swimming skills to continue its flight.

Part of the iguana family, green basilisks grow to about 2 feet (61 centimeters) in length, including their long, whip-like tail. Males have distinctive, high crests on their heads and backs, which they use to impress females.

Pregnant females prepare a shallow trench where they lay up to 20 eggs. The mother then leaves the eggs to hatch on their own. Hatchlings are born with the ability to run (on land and water), climb, and swim.

Green basilisks are omnivores, surviving on a diet of plant material, insects, fruit, and small vertebrates. They are common throughout their range and have no special status, but abundant natural predators like snakes and birds keep these amazing lizards on their toes.

Snowshoe Rabbit

Snowshoe rabbits are forest-dwellers that prefer the thick cover of brushy undergrowth. They are primarily a northern species that inhabits boreal forests and can also range as far north as the shores of the Arctic Ocean. Along North American mountain ranges, where elevation simulates the environment of more northerly latitudes, they can be found as far south as Virginia (the Appalachians) and New Mexico (the Rockies).

Hares are a bit larger than rabbits, and they typically have taller hind legs and longer ears. Snowshoe hares have especially large, furry feet that help them to move atop snow in the winter. They also have a snow-white winter coat that turns brown when the snow melts each spring. It takes about ten weeks for the coat to completely change color.

Snowshoe hares feed at night, following well worn forest paths to feed on trees and shrubs, grasses, and plants.

These animals are nimble and fast, which is fortunate, because they are a popular target for many predators. Lynx, fox, coyote, and even some birds of prey hunt this wary hare.

Like most hares (and rabbits), snowshoe hares are prolific breeders. Females have two or three litters each year, which include from one to eight young per litter. Young hares, called leverets, require little care from their mothers and can survive on their own in a month or less. Snowshoe hare populations fluctuate cyclically about once a decade—possibly because of disease. These waning and waxing numbers greatly impact the animals that count on hares for food, particularly the lynx.

Hedgehog

There are some 15 species of hedgehog in Europe, Asia, and Africa. Hedgehogs have also been introduced into nontraditional ranges such as New Zealand. The hedgehog was named because of its peculiar foraging methods. These animals root through hedges and other undergrowth in search of the small creatures that compose the bulk of their diet—insects, worms, centipedes, snails, mice, frogs, and snakes. As a hedgehog picks its way through the hedges it emits piglike grunts—thus, the hedgehog.

Some people consider hedgehogs useful pets because they prey on many common garden pests. While on the hunt, they rely upon their senses of hearing and smell because their eyesight is weak.

Hedgehogs have a coat of stiff, sharp spines. If attacked they will curl into a prickly and unappetizing ball that deters most predators. They usually sleep in this position during the day and awaken to search for food at night.

Hedgehogs hibernate in cold climates. In deserts, they sleep through heat and drought in a similar process called aestivation. They remain active all year in more temperate locations.

These solitary animals typically couple only for mating. The young born each year, in litters ranging from one to eleven, remain with their mothers for only four to seven weeks before heading out on their own. Among the predators females must guard against during this period are other male hedgehogs, which will sometimes prey upon the young of their species. Hedgehog mothers have also been known to eat their young if the nest is disturbed, though they sometimes simply move them to a new nest.