Why does a bird fly and not fall?

Quite often people, admiring the beauty of the sky, ask themselves: why does a bird fly? Why can not a man soar in the sky, admiring the beauty of the earth from a height?

The answer is obvious. First of all, birds have wings, which no man has. And if you look at the bird's wing more closely, you can see that it has a curved shape and is capable of creating a force that counteracts the force of gravity.

Poultry feathers are very light, but at the same timethe most complex horn formations of the skin, which in the course of evolution were transformed from scales of reptiles. It is thanks to feathers that the body surface of the bird is smooth, and when it flies, the air flows around her body without much resistance.

The skeleton of the birds is very light. Several bones in it contain air-bearing cavities. They do not have red bone marrow, as in humans. This is another answer to the question of why a bird flies, but a person does not.

Birds have a large heart, since when flying itshould ensure rapid blood circulation. In addition, their blood contains more erythrocytes than those of the same mammals, which means that the blood of birds can carry more oxygen per unit of time, which is very important for flight.

Birds are very well developed lungs. They are associated with air sacs that are located in the body cavity. In addition, they have a very developed cerebellum, which regulates the coordination of movements. All this is quite important for the flight.

There are planning and waving modes of flight. Planning is typical for predators, such as the golden eagle, eagle or hawk. The waving is divided into a hover and a horizontal flight. Most of the birds waving their wings, but the seagulls and cormorants during the flight hang.

Which bird flies above all

Here the indisputable leader is the African sip(refers to the type of vultures). With his participation such a case is fixed. In the mid-seventies of the last century, one of the vultures collided with a jet aircraft. And it happened at an altitude of more than 11 thousand meters (it should be said that Everest is 2 km below this altitude).

Why does the bird fly high, or rather why? Predators thus look out for their prey. This also applies to migratory individuals. For example, Indian geese rise in flight above the tops of the Himalayas, when they fly between Tibet and India, and do it twice a year.

Which of the birds are marine? Seabirds do not have many species - just a little more than 200 of the 9,500 all kinds of feathered modern fauna. These include the representatives of the tuberculosis: petioles, albatrosses, petrels. Most copepods: frigates, cormorants, foothills, phaetons. This includes gulls, eiders, dead ends, gagarki, guillemots, and, of course, penguins.

Gagar and cormorants can be called featheredsubmarines that perfectly dive and swim under water. And here the question "why the bird swims" is already pertinent, and not "why the bird flies". Sea birds have got on their paws membranes and leathery lids, which, when diving, cover the nostrils.

By the way, sea birds are rather awkwardmove on land. Most of the time they are on the water, feeding on fish. And, when they dive behind it, they reach a speed of up to 3 meters per second and go to a depth of several tens of meters.