Note: These are 360° videos — press and hold to explore them!
Tree of Life
Plant Flower, Tree
Invertebrate Octopus, Ant, Bee, Butterfly, Spider, Lobster
Vertebrate Fish, Seahorse, Ray, Shark, Frog, Turtle, Tortoise, Dinosaur
Bird, Ostrich, Owl, Crow, Parrot
Mammal Bat, Rabbit, Giraffe, Camel, Horse, Elephant, Mammoth
Whale, Dolphin, Walrus, Seal, Polar Bear, Bear, Cat, Tiger, Lion, Dog, Wolf
Monkey, Chimpanzee, Human
These are organized by a classification scheme developed exclusively for Cosma. More…
seal : any of numerous carnivorous marine mammals (families Phocidae and Otariidae) that live chiefly in cold regions and have limbs modified into webbed flippers adapted primarily to swimming — Webster
Seals, scientifically known as Pinnipeds, are a widely distributed and diverse clade of carnivorous, fin-footed, semiaquatic marine mammals. They comprise the extant families Odobenidae (whose only living member is the walrus), Otariidae (the eared seals: sea lions and fur seals), and Phocidae (the earless seals, or true seals). There are 33 extant species of pinnipeds, and more than 50 extinct species have been described from fossils. While seals were historically thought to have descended from two ancestral lines, molecular evidence supports them as a monophyletic lineage (descended from one ancestral line). Pinnipeds belong to the order Carnivora and their closest living relatives are bears and musteloids (weasels, raccoons, skunks, and red pandas), having diverged about 50 million years ago.
Seals range in size from the 1 m (3 ft 3 in) and 45 kg (99 lb) Baikal seal to the 5 m (16 ft) and 3,200 kg (7,100 lb) southern elephant seal, which is also the largest member of the order Carnivora. Several species exhibit sexual dimorphism. They have streamlined bodies and four limbs that are modified into flippers. Though not as fast in the water as dolphins, seals are more flexible and agile. Otariids use their front limbs primarily to propel themselves through the water, while phocids and walruses use their hind limbs. Otariids and walruses have hind limbs that can be pulled under the body and used as legs on land. By comparison, terrestrial locomotion by phocids is more cumbersome. Otariids have visible external ears, while phocids and walruses lack these. Pinnipeds have well-developed senses—their eyesight and hearing are adapted for both air and water, and they have an advanced tactile system in their whiskers or vibrissae. Some species are well adapted for diving to great depths. They have a layer of fat, or blubber, under the skin to keep warm in the cold water, and, other than the walrus, all species are covered in fur.
Although pinnipeds are widespread, most species prefer the colder waters of the Northern and Southern Hemispheres. They spend most of their lives in the water, but come ashore to mate, give birth, molt or escape from predators, such as sharks and killer whales. They feed largely on fish and marine invertebrates; but a few, like the leopard seal, feed on large vertebrates, such as penguins and other seals. Walruses are specialized for feeding on bottom-dwelling mollusks. Male pinnipeds typically mate with more than one female (polygyny), although the degree of polygyny varies with the species. The males of land-breeding species tend to mate with a greater number of females than those of ice breeding species. Male pinniped strategies for reproductive success vary between defending females, defending territories that attract females and performing ritual displays or lek mating. Pups are typically born in the spring and summer months and females bear almost all the responsibility for raising them. Mothers of some species fast and nurse their young for a relatively short period of time while others take foraging trips at sea between nursing bouts. Seals produce a number of vocalizations, notably the barks of California sea lions and the complex songs of Weddell seals. — Wikipedia
Phys.org - latest science and technology news stories Phys.org internet news portal provides the latest news on science including: Physics, Nanotechnology, Life Sciences, Space Science, Earth Science, Environment, Health and Medicine.
Record low level of Bering Sea ice causes...
on December 11, 2019 at 2:48 pm
Sea ice in the Bering Sea shrank to its lowest levels in recorded history in 2018, profoundly affecting northwest Alaska residents who depend on marine resources for food, cash and culture, according to a new peer-reviewed study.
Arctic has one of warmest years, raising fears...
on December 11, 2019 at 8:57 am
The Arctic has experienced its second warmest year since 1900, according to a report published Tuesday, raising fears over low summer sea ice and rising sea levels.
White Island: A look inside New Zealand's most...
on December 10, 2019 at 10:00 am
New Zealand's White Island exploded suddenly on Monday and almost instantly became the scene of unimaginable horror, but as the country's most active volcano a disaster was not entirely unexpected.
Cuneiform reveals shared birthplace
on December 6, 2019 at 2:00 pm
Assyriologists in Leiden have been conducting research into ancient clay tablets from the Middle East for 100 years already. What exactly do these clay tablets tell us? And why is Leiden such a good place to study them?
Life on Mars? Europe commits to groundbreaking...
on December 5, 2019 at 3:30 pm
It will be one of the most daunting, complicated and, potentially, scientifically rewarding missions ever undertaken to the red planet. Ministers at a recent meeting of the European Space Agency (ESA) have fully committed to plans to collect samples from the surface of Mars and return them to Earth, in a joint effort with NASA. Official approval for the NASA budget to cover this mission is anticipated early next year.