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Polar Vs. Brown Bear Essay, Research Paper

There are eight different species of bears found throughout

the world: the spectacled bear, the Asiatic black bear, the brown

bear (including grizzlies), the polar bear, the sun bear, the

American black bear, the sloth bear and the giant panda.

Even though most people can distinguish a polar bear from a brown

bear by the color of the fur, a lot of people fail to identify all the

differences among those two species. Both bears can be perceived as

large, clumsy and lumbering beasts with heavily built bodies but short

legs, necks and tails. Both of them have rounded ears and noticeably

small eyes relative to their large body size. While both of the bears

belong to same family, they have several profound differences. They

live in different geographical areas, differ in amount of the

population, size, physical features, some eating habits, and their

behavior toward human beings.

The polar bear is found in all of the polar regions of the entire

northern hemisphere. This includes Russia, Norway, Greenland, The

United States and Canada. Their preferred habitat is in the area where

the northern seas meet the shoreline. In this area, there is a constant

freezing and thawing of the ice. It is estimated that there are

currently somewhere between 20,000 and 40,000 polar bears.

The polar bear is the largest member of the bear family, weighing

in at between 440 and 1760 pounds with overall body length 11.5 feet.

It can grow much larger, however. In fact, there is a record of an

adult polar bear weighing over 2200 pounds.

Polar bears have a distinctive all white fur which is important

camouflage when hunting on the ice pack. Their actual color of the

skin is black which is thought to be an adaptation for better heat

retention. Compared to the other bears, the neck of polar bear is

much longer. This makes it easier for them to keep their heads above

water when swimming. Like those of other bears, the ears of the polar

bear are round. They are, however, smaller and closer to the head.

This also helps the animal to be an exceptional swimmer. The forepaws on a

polar bear are very large. With a diameter approaching 12 inches and

partial webbing between their toes, polar bears are able to use their

front feet much like paddles to propel them rapidly through the water.

Polar bears are excellent swimmers. They are able to swim distances

greater than 60 miles without a pause to rest, maintaining average

speed of 6 miles per hour. On land, they are not as quick as brown

bears and appear to have traded off speed for their extremely massive forelegs which they use to break through seal dens and to flip a large seal out of the water.

Polar bears have also developed large stomachs with a capacity of more than 150 pounds of food. Their digestive system is also more adapted for processing meat than plant material because they are almost exclusively meat eaters. While out on the ice, their diet consists mostly of marine mammals such as the ringed seals, bearded seals and occasionally a walrus or narwhal. Also, in keeping with their carnivorous nature, the canine teeth, used for seizing and holding prey, are longer, sharper and spaced wider apart than in brown bears.

Polar bear are at the top of the arctic food chain with no natural

enemies. Because of that, compared to other bears, polar bears are the

most aggressive and more willing to consider humans as a prey. In

other words, when they see a human, they see a walking meal.

Consequently the person attacked is usually killed unless the bear is

killed first. The most carnivorous, they are also the most patient and determined all of bears. In some instances they may follow a person for hundreds of miles in order to hunt him down. Out of eight species polar bear is considered to be the most dangerous to human beings.

The brown bear has the most widespread distribution in the world of

any of the eight bear species. They are found throughout most of the

northern hemisphere including North America and Eurasia. Their

preferred habitat includes mountain forests, open meadows and large

river valleys. It is estimated that there are currently somewhere

between 125,000 to 150,000 brown bears throughout the world.

The brown bear is one largest bear species, yet considerably smaller

than the polar bear. It weighs between 300 and 860 and can be up to 9.5

feet in total body length depending on the availability of food.

Brown bears can run and climb with considerable skill, speed and

dexterity. They are able to attain speeds of 35 mile per hour for a

short distance. They are also capable swimmers.

The brown bear distinguishes itself from other bears by virtue of

its shoulder hump, which is caused by muscles which are used for

digging. The front claws are approximately 1.7 times longer than the

rear claws and generally visible even from distance. The color of the

animal varies from a light creamy color to almost black.

Brown bears are omnivorous, eating a mixed diet of grasses, fruits,

bulbs and roots, insects, fish and small animals. In few areas there

are known to be predators of larger animals such as caribou and moose.

Each of the brown bears has a different temperament rather like

humans. Some will attack, others will not. Some bears are scared of

humans, others will have a have natural curiosity. Brown bears may be

very dangerous. However, most of the time a they more likely to

attack when defending cubs or territory. A stalking brown bear is even

a more rare occasion.

Even though polar and brown bears have a lot in common they differ in

many ways such as amount of population, size, areas of living, physical

characteristics and attitudes towards people. Scientists have studied these

magnificent animals for many years, but there is still much to learn about

them. They are very complex and fascinating creatures that deserve great

respect.

Bibliography

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