Σάββατο, 1 Φεβρουαρίου 2014

New Leviathan Whale Attacks

Illustration by C. Letenneur, Muséum National d'Histoire Naturelle, Paris, France
Evoking the poster for the original summer blockbuster, a new species of killer sperm whale attacks a baleen whale in an illustration.
Dubbed Leviathan melvillei—an homage to Moby-Dick author Herman Melville—the recently unearthed fossil sea monster lived about 13 million years ago in waters atop what's now a Peruvian desert, according to a study published by the journal Nature on Wednesday.
Living alongside the largest sharks ever known, the raptorial—meaning actively hunting—whale measured about 60 feet (18 meters) in length, about as big as a modern male sperm whale.
But whereas modern sperm whales feed primarily on squid, Leviathan's large teeth—some of which measured more than a foot (36 centimeters) long—suggest the whale hunted more challenging prey, including perhaps its close whale relatives.
"It was probably a very powerful and frightening animal, so it fits well with the description Melville made of Moby-Dick," said lead study author Olivier Lambert, a paleontologist at the National Museum of Natural History in Paris.


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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.
Blue whales reach these mind-boggling dimensions on a diet composed nearly exclusively of tiny shrimplike animals called krill. During certain times of the year, a single adult blue whale consumes about 4 tons (3.6 metric tons) of krill a day.
Blue whales are baleen whales, which means they have fringed plates of fingernail-like material, called baleen, attached to their upper jaws. 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. Then the whale's massive tongue forces the water out through the thin, overlapping baleen plates. Thousands of krill are left behind—and then swallowed.
Blue whales look true blue underwater, but on the surface their coloring is more a mottled blue-gray. Their underbellies take on a yellowish hue from the millions of microorganisms that take up residence in their skin. The blue whale has a broad, flat head and a long, tapered body that ends in wide, triangular flukes.
Blue whales live in all the world's oceans occasionally swimming in small groups but usually alone or in pairs. They often spend summers feeding in polar waters and undertake lengthy migrations towards the Equator as winter arrives.
These graceful swimmers cruise the ocean at more than five miles an hour (eight kilometers an hour), but accelerate to more than 20 miles an hour (32 kilometers an hour) when they are agitated. Blue whales are among the loudest animals on the planet. They emit a series of pulses, groans, and moans, and it’s thought that, in good conditions, blue whales can hear each other up to 1,000 miles (1,600 kilometers) away. Scientists think they use these vocalizations not only to communicate, but, along with their excellent hearing, to sonar-navigate the lightless ocean depths.
Really Big Babies
Blue whale calves enter the world already ranking among the planet's largest creatures. After about a year inside its mother's womb, a baby blue whale emerges weighing up to 3 tons (2.7 metric tons) and stretching to 25 feet (8 meters). It gorges on nothing but mother's milk and gains about 200 pounds (91 kilograms) every day for its first year.
Blue whales are among Earth's longest-lived animals. Scientists have discovered that by counting the layers of a deceased whale's waxlike earplugs, they can get a close estimate of the animal's age. The oldest blue whale found using this method was determined to be around 110 years old. Average lifespan is estimated at around 80 to 90 years.
Between 10,000 and 25,000 blue whales are believed to still swim the world's oceans. Aggressive hunting in the 1900s by whalers seeking whale oil drove them to the brink of extinction. Between 1900 and the mid-1960s, some 360,000 blue whales were slaughtered. They finally came under protection with the 1966 International Whaling Commission, but they've managed only a minor recovery since then.
Blue whales have few predators but are known to fall victim to attacks by sharks and killer whales, and many are injured or die each year from impacts with large ships. Blue whales are currently classified as endangered on the World Conservation Union (IUCN) Red List.
Type:
Mammal
Diet:
Carnivore
Average life span in the wild:
80 to 90 years
Size:
82 to 105 ft (25 to 32 m)
Weight:
Up to 200 tons (181,437 kg)
Group name:
Pod
Protection status:
Endangered
Did you know?
When a blue whale exhales, the spray from its blowhole can reach nearly 30 ft (9m) into the air.

Size relative to a bus:






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Hippopotamuses love water, which is why the Greeks named them the "river horse." Hippos spend up to 16 hours a day submerged in rivers and lakes to keep their massive bodies cool under the hot African sun. Hippos are graceful in water, good swimmers, and can hold their breath underwater for up to five minutes. However, they are often large enough to simply walk or stand on the lake floor, or lie in the shallows. Their eyes and nostrils are located high on their heads, which allows them to see and breathe while mostly submerged.
Hippos also bask on the shoreline and secrete an oily red substance, which gave rise to the myth that they sweat blood. The liquid is actually a skin moistener and sunblock that may also provide protection against germs.
At sunset, hippopotamuses leave the water and travel overland to graze. They may travel 6 miles (10 kilometers) in a night, along single-file pathways, to consume some 80 pounds (35 kilograms) of grass. Considering their enormous size, a hippo's food intake is relatively low. If threatened on land hippos may run for the water—they can match a human's speed for short distances.
Hippo calves weigh nearly 100 pounds (45 kilograms) at birth and can suckle on land or underwater by closing their ears and nostrils. Each female has only one calf every two years. Soon after birth, mother and young join schools that provide some protection against crocodiles, lions, and hyenas.
Hippos once had a broader distribution but now live in eastern central and southern sub-Saharan Africa, where their populations are in decline.
Type:
Mammal
Diet:
Herbivore
Average life span in the wild:
Up to 40 years
Size:
Head and body, 9.5 to 14 ft (2.8 to 4.2 m); tail, 13.75 to 19.75 inches (35 to 50 cm)
Weight:
5,000 to 8,000 lbs (2,268 to 3,629 kg)
Group name:
School
Size relative to a 6-ft (2-m) man:













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