Реферат на тему Brown Bear Essay Research Paper There are
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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.