Cosma Home > Communication > Knowledge > Realm > Terrestrial > Sphere > Life > Animal > Seal
Spotlight
Note: These are 360° videos — press and hold to explore them!
Related
Pages
Terrestrial (Earth)
Sphere Land, Ice, Water (Ocean), Air, Life (Cell, Gene, Microscope)
Ecosystem Forest, Grassland, Desert, Arctic, Aquatic
Tree of Life
Microorganism
Plant Flower, Tree
Animal
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
Resources
These are organized by a classification scheme developed exclusively for Cosma. More…
General
Dictionary
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
OneLook, Free Dictionary, Wiktionary, Urban Dictionary
Encyclopedia
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
Search
Preservation
Library
WorldCat, Library of Congress, UPenn Online Books, Open Library
Participation
Education
Course
OER Commons: Open Educational Resources
Community
News
Book
Government
Document
Expression
Fun
Seal slaps kayaker with octopus in viral GoPro video (Caitlin O ‘Kane, CBS NEWS)
Why Did An Octopus-Wielding Seal Slap A Kayaker In The Face? (Rachel D. Cohen, NPR)
Arts
Poem
OEDILF: The Omnificent English Dictionary In Limerick Form
More…
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.
-
Apollo moon rocks help transform understanding of...
on June 16, 2019 at 9:00 am
Moon rocks look rather nondescript—they are often gray in color—but for NASA planetary scientist Samuel Lawrence, they are the "most precious materials on Earth." […]
-
Enhanced human Blood-Brain Barrier Chip performs...
on June 13, 2019 at 9:00 am
Like airport security barriers that either clear authorized travelers or block unauthorized travelers and their luggage from accessing central operation areas, the blood-brain-barrier (BBB) tightly controls the transport of essential nutrients and energy metabolites into the brain and staves off unwanted substances circulating in the blood stream. Importantly, it's highly organized structure of thin blood vessels and supporting cells is also the major obstacle preventing life-saving drugs from […]
-
Pulsed electron beams shed light on plastics...
on June 12, 2019 at 12:15 pm
Plastics are all around us—they make up our water bottles, trash bags, packing materials, toys, containers, and more. About 300 million tons of plastic are produced worldwide each year, yet the details of what goes on at the atomic scale during the plastics production process is still unclear. […]
-
Climate change benefits for giant petrels
on June 12, 2019 at 7:00 am
Giant petrels will be "temporary" winners from the effects of climate change in the Antarctic region—but males and females will benefit in very different ways, a new study shows. […]
-
Shape memory alloy technology leads to...
on June 11, 2019 at 11:10 am
A team of University of North Texas College of Engineering seniors have created an energy efficient system for controlling solar panels on CubeSats using a nickel-titanium shape memory alloy. […]