2. African Elephants are the largest of Earth's land mammals. Their enormous ears help them to keep cool in the hot African climate. (Asian elephants have smaller, rounded ears.) An elephant's trunk is actually a long nose used for smelling, breathing, trumpeting, drinking, and also for grabbing things—especially a potential meal.
3. The American Alligator is a rare success story of an endangered animal not only saved from extinction but now thriving. State and federal protections, habitat preservation efforts, and reduced demand for alligator products have improved the species' wild population to more than one million and growing today.
4. Anaconda: Member of the boa family, South America’s green anaconda is, pound for pound, the largest snake in the world. Its cousin, the reticulated python, can reach slightly greater lengths, but the enormous girth of the anaconda makes it almost twice as heavy.
5. Ants are common insects, but they have some unique capabilities. More than 10,000 known ant species occur around the world. They are especially prevalent in tropical forests, where they may comprise up to half of all the insects living in some locations.
6. Anteaters are edentate animals—they have no teeth. But their long tongues are more than sufficient to lap up the 35,000 ants and termites they swallow whole each day. The anteater uses its sharp claws to tear an opening into an anthill and put its long snout and efficient tongue to work. But it has to eat quickly, flicking its tongue up to 160 times per minute.
7. Camel: Arabian Camels, also known as dromedaries, have only one hump, but they employ it to great effect. The hump stores up to 80 pounds (36 kilograms) of fat, which a camel can break down into water and energy when sustenance is not available. Camels rarely sweat, even in desert temperatures that reach 120°F (49°C), so when they do take in fluids they can conserve them for long periods of time. A very thirsty animal can drink 30 gallons (135 liters) of water in only 13 minutes.
8. Black Bears are North America's most familiar and common bears. They typically live in forests and are excellent tree climbers, but are also found in mountains and swamps. Despite their name, black bears can be blue-gray or blue-black, brown, cinnamon, or even (very rarely) white. Black bears are very opportunistic eaters.
9. Blue Whales are the largest animals ever known to have lived on Earth. These magnificent marine mammals rule the oceans at up to 100 feet (30 meters) long and upwards of 200 tons (181 metric tons). Their tongues alone can weigh as much as an elephant. Their hearts, as much as an automobile. The giant animals feed by first gulping an enormous mouthful of water, expanding the pleated skin on their throat and belly to take it in. Blue whales live in all the world's oceans, occasionally swimming in small groups but usually alone or in pairs.
10. Domestic Cats , no matter their breed, are all members of one species. Cat has had a very long relationship with humans. Ancient Egyptians may have first domesticated cats as early as 4,000 years ago. Domestic cats remain largely carnivorous, and have evolved a simple gut appropriate for raw meat.
11. Dogs were probably the first tame animals. They have accompanied humans for some 10,000 years. Some scientists assert that all dogs, domestic and wild, share a common ancestor in the small South Asian wolf. Today humans have bred hundreds of different domestic dog breeds—some of which could never survive in the wild.
12. Scorpions are members of the class Arachnida and are closely related to spiders, mites, and ticks. These hardy, adaptable insects have been around for hundreds of millions of years, and they are nothing if not survivors. There are almost 2,000 scorpion species, but only 30 or 40 have strong enough poison to kill a person.
13. Wolves are legendary because of their spine-tingling howl, which they use to communicate. A lone wolf howls to attract the attention of his pack, while communal howls may send territorial messages from one pack to another. Some howls are confrontational. Much like barking domestic dogs, wolves may simply begin howling because a nearby wolf has already begun. Wolves are the largest members of the dog family.
14. Red foxes live around the world in many diverse habitats including forests, grasslands, mountains, and deserts. They also adapt well to human environments such as farms, suburban areas, and even large communities. The red fox's resourcefulness has earned it a legendary reputation for intelligence and cunning. Red foxes are solitary hunters who feed on rodents, rabbits, birds, and other small game—but their diet can be as flexible as their home habitat. Foxes will eat fruit and vegetables, fish, frogs, and even worms.
15. Black-Widow-Spider: This spider's bite is much feared because its venom is reported to be 15 times stronger than a rattlesnake's.
16. Rabbits: These rabbits seek out habitat on the fringes of open spaces, such as fields, meadows, and farms, but can adapt to other habitats—including those of humans.
17. 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.
18. Horses and humans have an ancient relationship. Asian nomads probably domesticated the first horses some 4,000 years ago, and the animals remained essential to many human societies until the advent of the engine. Horses still hold a place of honor in many cultures, often linked to heroic exploits in war.
19. Bull Sharks favor shallow coastal waters. Bull sharks are aggressive, common, and usually live near high-population areas like tropical shorelines. They are not bothered by brackish and freshwater, and even venture far inland via rivers and tributaries.
20. The Cheetah is the world's fastest land mammal. With acceleration that would leave most automobiles in the dust, a cheetah can go from 0 to 60 miles (96 kilometers) an hour in only three seconds. These big cats are quite nimble at high speed and can make quick and sudden turns in pursuit of prey.
21. Chimpanzees are generally fruit and plant eaters, but they also consume insects, eggs, and meat, including carrion. They have a tremendously varied diet that includes hundreds of known foods. Chimpanzees are one of the few animal species that employ tools. They shape and use sticks to retrieve insects from their nests or dig grubs out of logs.
22. The Coyote appears often in the tales and traditions of Native Americans—usually as a very savvy and clever beast.
23. Dolphins are well known as the intelligent and charismatic stars of many aquarium shows. Their curved mouths give the appearance of a friendly, permanent smile, and they can be trained to perform complex tricks. In the wild, these sleek swimmers can reach speeds of over 18 miles (30 kilometers) an hour. They surface often to breathe, doing so two or three times a minute.
24. Komodo Dragons have thrived in the harsh climate of Indonesia's Lesser Sunda Islands for millions of years, although amazingly, their existence was unknown to humans until about 100 years ago.
25. Duck: The green head and yellow bill of the mallard duck is a familiar sight to many people living in the Northern hemisphere. In fact, the mallard is thought to be the most abundant and wide-ranging duck on Earth.
26. Golden Eagles use their speed and sharp talons to snatch up rabbits, marmots, and ground squirrels. They also eat carrion, reptiles, birds, fish, and smaller fare such as large insects.
27. 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 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
28. Lions : Fiercely protective of his pride, or family unit, male lions patrol a vast territory normally covering about 100 square miles (260 square kilometers) Lions are the only cats that live in groups, which are called prides. Prides are family units that may include up to three males, a dozen or so females, and their young. Female lions are the pride's primary hunters.
29. Locusts are related to grasshoppers and the two insects look similar. However, locust behavior can be something else entirely.
30. Monarch Butterflies are known for the incredible mass migration that brings millions of them to California and Mexico each winter.
31. Rhesus Monkeys are familiar brown primates with red faces and rears. They have close-cropped hair on their heads, which accentuates their very expressive faces. Rhesus monkeys are Asian, Old World monkeys. Their natural range includes Afghanistan, Pakistan, India, Southeast Asia, and China.
32. Mosquitoes: Few animals on Earth evoke the antipathy that mosquitoes do. Their itchy, irritating bites and nearly ubiquitous presence can ruin a backyard barbecue or a hike in the woods. They have an uncanny ability to sense our murderous intentions, taking flight and disappearing milliseconds before a fatal swat. And in our bedrooms, the persistent, whiny hum of their buzzing wings can wake the soundest of sleepers.
33. Ostrich: The flightless ostrich is the world's largest bird. They roam African savanna and desert lands and get most of their water from the plants they eat. Though they cannot fly, ostriches are fleet, strong runners.
34. The Great Horned Owl is the most common owl of the Americas, easily recognizable because of the feather tufts on its head. These "plumicorns" resemble horns or, to some, catlike ears.
35. Penguins (Adélie) live on the Antarctic continent and on many small, surrounding coastal islands. They spend the winter offshore in the seas surrounding the Antarctic pack ice.
36. The Parrots are a broad order of more than 350 birds. Most parrots eat fruit, flowers, buds, nuts, seeds, and some small creatures such as insects. Parrots are found in warm climates all over most of the world.
37. 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.
38. 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.
39. Rhinoceroses: Both black and white rhinoceroses are actually gray. They are different not in color but in lip shape. The black rhino has a pointed upper lip, while its white relative has a squared lip. The difference in lip shape is related to the animals' diets. Black rhinos are browsers that get most of their sustenance from eating trees and bushes. They use their lips to pluck leaves and fruit from the branches.
40. Squirrels are familiar to almost everyone. More than 200 squirrel species live all over the world, with the notable exception of Australia.
41. Tarantulas give some people the creeps because of their large, hairy bodies and legs. But these spiders are harmless to humans (except for a painful bite), and their mild venom is weaker than a typical bee's. Among arachnid enthusiasts, these spiders have become popular pets.
42. 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.
43. Tigers are the largest members of the cat family and are renowned for their power and strength. Tigers live alone and aggressively scent-mark large territories to keep their rivals away. They are powerful nocturnal hunters that travel many miles to find buffalo, deer, wild pigs, and other large mammals.
44. Domestic Turkeys have white-tipped tails because they are the descendants of a Mexican subspecies that was taken to Europe for domestication in the early 16th century. The feature distinguishes them from most modern wild turkeys, though captive diet, lifestyle, and breeding have caused other physical discrepancies.
45. Zebra: No animal has a more distinctive coat than the zebra. Each animal's stripes are as unique as fingerprints—no two are exactly alike—although each of the three species has its own general pattern. Zebras are social animals that spend time in herds. They graze together, primarily on grass, and even groom one another.