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The red-tailed hawk is a top predator. The hawks use tall perches to spot their prey in the open spaces next to highways. Red-tailed hawks also hunt from the air. As they circle and soar, they can spot a mouse from 100 feet (30 meters) up in the air—about ten stories high. When a red-tailed hawk spots a rodent, rabbit, lizard, or other prey scurrying, it swoops down and grabs its meal in its talons—the big claws on its feet. Once the hawk grabs its prey, it usually flies back up to its perch to eat it. They were named for the variety that has a brick-red tail. Male and female red-tailed hawks basically look alike, though the females are larger. Red-tailed hawks often mate for life. The pair makes a stick nest in a tree, high above the ground. They will use the nest year after year, so it grows bigger and bigger. The female hawk lays one to five eggs—which are white with brown spots. The parents take turns sitting on the eggs, keeping them warm and safe. Baby red-tailed hawks are covered with white, downy feathers. The hawk parents feed their young until the young birds can leave the nest, usually when they’re about six weeks old.
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Scorpions are arachnids and have eight legs like their cousins—spiders, mites, and ticks. They can quickly grab an insect with their pincers and whip their telson, the poisonous tip of their tail forward and sting their prey. They use their poison to kill prey and to defend against predators. Scorpions look like small lobsters and may be the first animals to move from water to land hundreds of millions of years ago. They have been around since before the age of the dinosaurs. Fossils of scorpions from Scotland hundreds of millions of years ago show that their appearance hasn’t changed over the millennia, but they are now half the size of their ancient ancestors. Only 30 or 40 species around the world have strong enough poison to kill a person. Each species has a special type of venom that works well against a chosen prey. Scorpions typically eat insects, but when food is scarce, they can slow their metabolism to as little as one-third the typical rate for arthropods. This technique enables some species to use little oxygen and live on only one insect per year. Such survival skills allow scorpions to live in some of the planet’s toughest environments. Researchers have even frozen scorpions overnight, only to put them in the sun the next day and watch them thaw out and walk away. However, they are burrowing animals, so in areas of permafrost or heavy grasses, where loose soil is not available, scorpions may not be able to survive.
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Space explorers go above and beyond on the job. Here are five cool things about these pioneers.
You won’t find baths or showers in space.

A female red-eyed tree frog has laid a batch of eggs on a leaf. She chose the spot carefully—the leaf hangs over a pond. When the eggs are ready to hatch, the tadpoles inside start swirling around vigorously. The activity breaks each egg open, releasing the little tadpoles. All the tadpoles wash down the leaf in a little stream of moisture from the hatching eggs, and—plop! plop! plop!—they land in the pond below. Feeding on tiny insects, the tadpoles live in the water they fell into until they metamorphose, or develop, into little brown froglets. At this point they leave the water and climb up nearby trees to live as tree frogs. By the time they’re adults, the frogs have turned a striking green, with blue-and-yellow striped sides, orange or red feet, a flash of blue on their thighs, and big red eyes. The bright colors are a defense mechanism. Being green helps the red-eyed tree frog blend in with tree leaves. If the green camouflage fails and a predator spots a sleeping frog, it swoops in for what it thinks will be a tasty meal. But the awakened frog’s eyes pop open, revealing their startling bright red color! Also, when the frog rushes to get away, it untucks its brightly colored legs. The predator is often so surprised by these sudden flashes of color that it is momentarily confused and hesitates. And while it does, the frog has a split second to make its escape!
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Goblin Shark
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The Gila monster is one of only a few poisonous lizards in the world. The Gila (pronounced HEE-luh) is the largest lizard native to the United States. Their black bodies are covered in beadlike scales with bright spots, blotches, or bands of pink, orange, or yellow, which probably warn other animals to stay away. Their bulky bodies, slow-moving stride, thick forked tongue, and snorting hisses reinforce the name Gila monster. They live in the dry, arid regions such as the Mojave, Sonoran, and Chihuahuan Deserts of the southwestern U.S. and northwestern Mexico. They are named after the Arizona Gila River Basin, where they were first discovered. Gila monsters are more likely to use their venom on a predator than on prey. They clamp their jaws down with the power of a vise grip. Then the venom in their bottom jaw flows through their grooved teeth into the victim. Although the Gila’s bite is extremely painful, no human death has been reported. Gilas are sluggish creatures that feed primarily on eggs raided from bird nests and newborn mammals, such as rabbits and squirrels. They sometimes eat quail eggs whole without crushing the shells. They spend about 95 percent of their time underground and emerge only to hunt for food or to take a sunbath. They don’t need to eat very often because they can store fat in their large tails.
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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. At birth the baby shark is already about 5 feet (1.5 meters) long; as it grows it may reach a length up to four times that. The pup (which is what a baby shark is called) will live its life at the top of the ocean’s food chain. But before it grows larger, the pup must avoid predators bigger than it is—including other great white sharks. Many baby sharks do not survive their first year. Young great white sharks eat fish (including other sharks) and rays. As they grow, the sharks’ favorite prey becomes sea mammals, especially sea lions and seals. Sharks count on the element of surprise as they hunt. When they see a seal at the surface of the water, sharks will often position themselves underneath the seal. Using their tails as propellers, they swim upward at a fast sprint, burst out of the water in a leap called a breach, and fall back into the water with the seal in their mouths. They can smell a single drop of blood from up to a third of a mile (0.53 kilometers) away. Sharks don’t chew their food; they rip off chunks of meat and swallow them whole. They can last a month or two without another big meal.
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The ostrich is the tallest and the heaviest of all birds. While the huge ostrich is a bird, it does not fly. Instead it runs. One stride can cover up to 16 feet (4.9 meters)—about the length of a mid-size family car! The bird is speedy, too. It can run just over 40 miles (64 kilometers) an hour for a short distance, and can keep up a speed of more than 30 miles (48 kilometers) an hour over longer distances. The ostrich uses its short wings for balance, holding them outstretched when it runs. Strong legs can also be used for self-defense. An ostrich will kick with a force mighty enough to kill a lion. When danger approaches, an ostrich will often lie low to hide, stretching its neck along the ground. Its feather colors blend with the sandy soil where it lives. From far away, it looks like the ostrich has buried its head in the sand. Many people thought that was what ostriches did when they were trying to hide, but that is a myth. Ostriches live near grazing animals such as wildebeest, antelopes, and zebras. The grazers stir up insects and rodents for the ostriches to eat, and the ostriches warn the grazers to dangers such as approaching lions. An ostrich group, called a herd, numbers about 12 individuals. Male ostriches compete for control of a group of several females. A herd has a dominant male and a dominant female. She mates only with him, though he may mate with other females as well. All the egg-laying females, called hens, lay their eggs in the nest of the dominant female. Then that female—whose eggs are positioned in the center of the nest, the most well-protected spot—and her mate take care of all the eggs in that one nest. Each egg can be up to 6 inches (15 centimeters) long and weigh 3 pounds (1.5 kilograms)!
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Axolotls (pronounced ACK-suh-LAH-tuhls) are salamanders! Thes amphibians spend their whole lives underwater. They exist in the wild in only one place on Earth—the lake complex of Xochimilco (pronounced SO-chee-MILL-koh), a network of artificial channels, small lakes, and temporary wetlands that help supply water to the millions of residents in nearby Mexico City. Axolotls have long fascinated scientists for their ability to regenerate lost body parts and for their rare trait of neoteny, which means they retain larval features throughout life. Rather than undergoing typical metamorphosis, axolotls keep their youthful appearance, including their tadpolelike dorsal fin and feathery external gills that fan out from the head. As they age, axolotls simply get bigger and bigger, like amphibious Peter Pans. In rare cases, axolotls have matured past the larval stage and emerged onto land as adult salamanders. Neoteny doesn’t affect the axolotl’s ability to breed. Females mate with males and lay eggs underwater. As Mexico City has grown, the lake complex has shrunk and parts have become contaminated, distressing the axolotl population. The introduction of large numbers of carp and tilapia fish, which compete with axolotls for food and also eat axolotl eggs, has further lowered their population. A 2009 survey suggests there are fewer than 1,200 axolotls in the Xochimilco Lake complex. Axolotls feast on a menu of mollusks, worms, insect larvae, crustaceans, and some fish.
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When you see a snowy owl, it’s clear how the bird probably got its name: they’re snow-white. Males are generally whiter than females. As males grow older, they get whiter. The females never become completely white—remaining brownish with darker markings. These large owls mainly live in the Arctic in open, treeless areas called tundra. Snowy owls perch on the ground or on short posts. From there they patiently watch for prey. Their favorite target is lemmings—small mouselike rodents—but they also hunt for other small rodents, rabbits, birds, and fish. Snowy owls have excellent eyesight, but they obviously can’t see their prey when it’s underneath snow or a thick layer of plants. To capture those meals, the owl relies on its other keen sense: hearing. In flight, snowy owls generally cruise low to the ground. Once they spot their prey, they approach it from the air, and snatch it up using the large, sharp talons, or claws, on their feet. Most owls sleep during the day and hunt at night, but the snowy owl is active during the day, especially in the summertime. They tend to be most active at dawn and dusk. Snowy owl pairs usually mate for life. Female snowy owls lay from 3 to 11 eggs at a time, in a nest built on the ground. When there is plenty of food available, snowy owls tend to lay more eggs than when food is scarce. Lemmings make up the main part of the snowy owls‘ diet, and lemming population numbers rise and fall naturally. Sometimes, if there is not enough prey around to feed baby owls, the adult pair won’t lay any eggs at all until the supply of food improves. The female snowy owl sits on her eggs until they hatch. The male feeds her while she keeps their eggs warm and safe. After about one month, the eggs hatch. Babies are covered in soft white down when they hatch. As new feathers replace the down, the birds become light brown. The young leave the nest less than a month after they hatch. By the time they’re about a month and a half old, the young owls can fly well, but their parents take care of them for another ten weeks or more.
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