Animals in Arctic and Antarctic
Animals in Arctic and Antarctic
Artic and Antarctic a very cold and sizzling area.In this article by haveprasad
We will discover some unknown and verified facts and figures from the Arctic and the Antarctic. Which includes
their location ,their specialty about the animal which resides in the Arctic and Antarctic. But to know about arctic and Antarctic we should khow about ocean and seas.Here we will get the answer for the following questions
Oceans and seas
OCEANS AND SEAS COVER ABOUT 70 Per cent of the Earth's surface and account for about 97 per cent of its total water. These oceans and seas play a crucial role in regulating temperature variations and determining climate. Their waters absorb heat from the Sun, especially in tropical regions, and the surface currents distribute it around the Earth, warming overlying air masses and neighbouring land in winter and cooling them in summer. The oceans are never still. Differences in temperature and salinity drive deep current systems, while surface currents are generated by winds blowing over the oceans. All currents are deflected to the right in the Northern Hemisphere, to the left in the Southern Hemisphere- as a result of the Earth's rotation. This deflective factor is known as the Coriolis force. A current that begins on the surface is immediately deflected. This current in turn generates a current in the layer of water beneath, which is also deflected. As the movemem is transmitted downwards, the deflections form an Ekman spiral. The waters of the oceans and seas are also moved by the constant ebb and flow of tides. These are caused by the gravitational pull of the Moon and Sun .The highest tides (Spring tides) occur at full and new Moon the lowest tides (neap tides) oonur at first and last quarter. Different types of salts are present in the sea water.For further reference of sea water contents refer to the picture
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| Salt content of sea water |
What is the difference between Arctic and Antarctic?
The areas around the north and the south poles are called the Arctic and the Antarctic regions, respectively. Both these regions are cold and are covered with ice. But there is a big difference between the two: there is sea water below the Arctic ice cap, and there is rocky mainland below the Antarctic ice cap. The fauna is also not the same. Penguins live in the Antarctic and are not found in the north pole. Many seabirds such as the albatross also breed in the Antarctic. In the Arctic, which ranges from Scandinavia to Siberia via Greenland, North Canada, and Alaska, polar bears and a species of seals with huge tusks, called the walrus, are found. Huge whales swim off the coast of both the polar regions. They feed on krill and are famous for their hunting technique.
How do animals protect themselves against cold?
Penguins have a thick plumage and a thick layer of fat. In addition, their body shape-a lot of mass with the smallest possible surface-ensures that the animals lose very little of their body heat. Polar bears protect themselves with the help of a layer of fat, but they also have another heating mechanism. Individual hairs of their fur are hollow and conduct the little sunlight available to the skin like glass fibre cables. Their skin is black-not bright like other animals and black stores heat. Since the undercoat of the polar bear's hide is very thick, body heat is not lost; therefore, the polar bear is able to survive even the freezing cold of the Arctic.
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How do animals protect themselves against cold? |
- the lowest temperature ever recorded on Earth is -89.2°C? It was measured in East Antarctic.
- the poles are the tunnel points of the Earth's axis? This can be seen clearly on a globe.
- emperor penguins grow to a height of about 1.20 m, but fairy penguins grow to a height of 30 cm only?
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| Emperor penguins live in the Antarctic. Once every year they migrate to their breeding ground 200km away. |
Sponges, jellyfish, and sea anemones
SPONGES ARE MAINLY MARINE animals that make up the phylum Porifera. They are among the simplest of all animals, having no tissues or organs. Their bodies consist of two layers of cells separated by a jelly-like layer (mesohyal) that is strengthened by mineral spicules or protein fibres. The body is perforated by a system of pores and water channels called the aquiferous system. Special cells (choanocytes) with whip-like structures (flagella) draw water through the aquiferous system, thereby bringing tiny food particles to the sponge's cells, Jellyfish (class Scyphozoa). sea anemones (class Anthozoa), and corals (also class Anthozoa) belong to the phylum Cnidaria, also known as Coelenterata. More complex than sponges, coelenterates have simple
tissues, such as nervous tissue; a radially symmetrical body; and a mouth surrounded by tentacles with unique stinging cells (enidocytes).
What do the walruses use their tusks for?
Male walruses show their age and social rank in the herd through the length of their tusks. They use them to form and maintain holes in the ice and in climbing out of water onto ice. They do not need the tusks for hunting because they feed mainly on shells and small animals. Like the tusks of elephants, walrus tusks have been used for tools as well as material for handicrafts. The Eskimos, who have been feeding on walruses for centuries, make artistic carvings from the tusks.
How do orcas (killer whale )hunt?
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| Since seal cannot run fast it is often too late for them to escape when they see the approaching orcas. |
Killer whales (Orcinus orca), known as orca, are among the most intelligent marine predators. They hunt mostly in groups of more than five animals. They hunt fish, seabirds, seals, dolphins, and other whales and employ different hunting techniques. They hit their powerful tailfins in a swarm of herrings to stun them. They also use the wave-hunting technique: they create strong waves to wash seals off floating ice. They even attack gray whales after isolating an individual animal from the group.
