Dein Suchergebnis zum Thema: Bäcker

Mexican axolotl (pronounced ACK-suh-LAH-tuhl) salamanders are amphibians that spend their whole lives underwater. They exist in the wild in only one place—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 nearby Mexico City’s 18 million residents. 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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sometimes break off, but they regenerate, or grow back

Long, white tusks break the surface of the icy Arctic water. It’s not a waterlogged herd of unicorns—it’s a pod of narwhals! This species of whale is best known for its tusk—a long, spiraled tooth that usually only the males develop. (Females occasionally do.) The tusk can grow to 9 feet (3 meters) long and weigh more than 22 pounds (10 kilograms). MYSTERY TOOTH Scientists don’t know exactly why narwhals have tusks—though they might be used to impress females or fight other males. But tusks are more than battle swords—they’re packed with nerves and covered in tiny holes that allow seawater to enter. This gives tusks a sensitivity that could help narwhals detect changes in their environment such as temperature or even the water’s saltiness. Clues like these might help narwhals find prey or survive in other ways. REAL-LIFE UNICORN Narwhals‘ Arctic habitat makes them difficult to study, and scientists still have plenty to learn about them. These unicorns of the sea might be mysterious, but they’re certainly no myth. Text by Allyson Shaw /NGS Staff
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Hold your own family cooking competition.
Once the soup comes back to a simmer, taste to check

Reaching up to 13 feet (4 meters) long and weighing as many as 1,300 pounds (600 kilograms), West Indian manatees look more like small cars than people. Despite their large size, manatees are graceful swimmers. Although they usually move along in slow motion, they can also cruise, or swim at a steady pace, at five miles (eight kilometers) an hour. In short bursts they can even top 15 miles (24 kilometers) an hour! While cruising, manatees push themselves forward by moving their strong tails up and down. They steer with the help of their flexible flippers. When in shallow water, manatees use their flippers to walk, slowly placing one in front of the other. Like whales and dolphins, manatees are mammals. Although they live in water, they have to surface frequently to breathe air. While swimming, manatees take in air every three or four minutes. When they are resting, they can stay underwater for up to 15 minutes. Manatees are gentle animals. They rarely fight, and they have no natural enemies. Subsisting on water plants and plants that grow at the water’s edge, a manatee takes in up to 1 pound (0.5 kilogram) of food for every 10 pounds (5 kilograms) it weighs.
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Snowy white tundra swans breed in the Arctic. Young swans have fluffy gray feathers in their first winter. The tundra swan call is higher and more like that of a Canada goose. Tundra swans mate for life and pair up for nearly a year before breeding. They breed in solitary pairs spread out across the Arctic tundra. They can be nasty protectors and are able to fend off predators like foxes. They prefer to nest near wetlands containing pondweed. They line their large, stick nests with moss and grasses. Females lay about four eggs and incubate them for 32 days. These large birds feed by dipping their heads underwater to pluck aquatic plants, roots, and tubers. Their diet consists of mainly submerged plants and roots, but they will also eat some cereal grains, corn, and mollusks, which are a kind of shellfish. The majestic tundra swan is a strong swimmer and can take off from the water with a running start and beat their wings until airborne. Their flapping wings produce a sound that earned them the name „whistling swan.“ They migrate thousands of miles to enjoy a milder winter in North America’s Atlantic and Pacific coastlines, bays, and lakes. Twice a year, they fly 3,725 miles (6,000 kilometers) round-trip between the breeding and wintering locations.
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Giraffes grow about 4 feet (1.2 meters) in their first year of life. A newborn giraffe is about 6 feet (1.9 meters) tall at birth and weighs about 150 pounds (68 kilograms). Many young giraffes, called calves, die from lion attacks during their first year of life. Once a giraffe reaches adulthood its height is often enough to protect it from lions. Adult giraffes, however, must still be careful of lions when they are bending down to drink water or rest. Usually giraffes will drink or rest in shifts so that at least one giraffe is always on the lookout for approaching predators. The giraffes‘ height and excellent vision give them a wide view of the grasslands where they live, making it easy to spot predators from a distance. Some scientists believe that other animals—such as zebras, antelope, and wildebeests—often congregate near giraffes to take advantage of their ability to see danger from a distance. The giraffe could be considered the early warning system of the African grasslands.
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The bald eagle has been the national symbol of the United States since 1782. Find out why these majestic birds are so cool.
prey with its feet and use its wings as oars to row back

If you live in the contiguous United States, you’ve almost certainly seen (or heard!) an American crow. Crows range from southern Canada throughout the United States. As an adult, this bird is entirely black from bill to tail, except for its brown eyes. Adult crow feathers have a glossy sheen. These noisy birds are often recognizable by their distinctive, loud cry, called a caw. They are often mistaken for the common raven, but ravens are larger, have differently shaped bills, pointed wings and tails, and hoarser cries. American crows often live in family groups. Both members of a breeding pair help build the nests, and the female crow usually lays four or five eggs in the spring or summer. After about five weeks in the nest, the young birds begin learning how to fly and catch prey. Crows sometimes stay near the place where they were born to help raise other young crows. Crows gather in large groups during the winter. They congregate late in the day in areas with large trees. This behavior is known as winter roosting. Crows will eat almost anything, from insects and small animals such as frogs to fruit and nuts. They prefer open areas with access to trees and can sometimes be found around vegetable gardens. Crows also frequently live in suburban neighborhoods and in parks. Crows are considered to be very intelligent birds. Text by Sara Zeglin / NGS Staff
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Read about the famous Chincoteague Pony Swim. The annual event is an effort to control the area’s feral pony population.
adult ponies, along with seven foals, were herded back