External structure of birds, its features

Studying the external structure of birds allowed scientists to establish characteristic features, due to which they adapted to the flight. It is their presence that makes these animals absolutely unique representatives of the chord type.

Features of the structure of birds

The ancestors of birds are reptiles. And this is not just an assumption. The uneven part of the bird's leg, which is called a crook, is devoid of feather cover and covered with scales. They have a similar structure with the same structures in lizards and snakes. In the course of evolution, the birds acquired progressive features of the structure. This is the appearance of a four-chambered heart in which a partition is located. Thanks to her venous and arterial blood is completely separated. This change led to the emergence of warm-bloodedness. It is the ability to maintain a constant body temperature that does not depend on environmental conditions. Due to this, birds can stay for a long time at a high altitude in conditions of low temperatures.

The external structure of birds also determines their ability to fly.

Body parts

The body of the birds consists of the head, neck, trunk and extremities. They all have their own characteristics, often associated with conditions of existence. On the head are the eyes. Their size varies depending on how large the body is. In predators, eyes are the same in volume by volume. And in chicken by weight are equal to their brain. All birds are able to distinguish colors. And the acuity of their eyesight is amazing. For example, the Peregrine predator clearly sees the prey at a distance of about 1 km.

The head of the birds is very mobile. Owls, looking for prey, are able to rotate it 270 degrees.

Features of the external structure of birds are due not only to the ability to fly, but also the nature of the food. First of all, it concerns the structure of the beak. It is the initial department of the digestive system, which leads into the oral cavity.

Beak

Beak is the calling card of every bird. It is formed of a hard horny substance. Its constituent parts are over- and plug-in. The beak will replace the birds with many organs, performing the functions of the oral apparatus, nose and forelimbs.

The variety of the shape of the beaks is determined by the nature of the food. The herons, which prey on water inhabitants, it is long and sharp. With its help, these birds can easily catch a frog or pierce through the fish. A crossed beak can easily crack cones and extract seeds from them.

Predators attack their prey. At the same time, with the help of an acute bent beak, they easily tear it to pieces.

The woodpecker produces food in a different way: its beak is like a chisel. The bird makes holes in the wood, from which the larvae of insects are extracted.

Features of the limbs

The external structure of birds is also due to the structure of the limbs. The upper ones are turned into wings. Their skeleton consists of a shoulder, a forearm and a brush. Cover feathers are attached to the wings of the wings. Such a structure makes birds capable of flying. Wings drive specialized muscles, which are attached to the flat bone - keel.

With the help of the lower extremities, the bird lands and repels from the ground, moves along the surface. And flexible toes allow you to hold on to any surface. They end with sharp claws, which are especially well developed in predators. They falcons, golden eagles and peregrine falconers sacrifice, not giving her even the slightest chance.

Covers

The skin of these animals is dry and devoid of glands, like reptiles. However, waterfowl have an oil gland. With the secretions of her fat-like secret, they smear feathers. As a result, they do not absorb moisture.

The unique external structure of birds is due to the presence of feather cover. It is a derivative of the skin.

Depending on the features of the structure and the functions performed, several types of feathers are distinguished. Contour are divided into mahovye, covering and helmsmen. The first are located on the wings and provide the ability to fly. Coverers are similar in location and function. And the steering is concentrated on the tail, performing the role of helmsman during the flight, helping the birds to perform rather complex maneuvers. At the heart of the contour feather is a horn rod surrounded by a fan. It, in turn, consists of the beards of several orders, tightly connected by hooks. The part of the rod, devoid of a fan and immersed in the skin, is called the eye.

The next variety of feathers are downy. They are located under contour. Their functions are to maintain the heat and thermal insulation of the body. A similar function is performed by the fluff, in which the beards leave a bundle in the form of a brush.

Some species of birds have specialized thread-like feathers. Located in the corners of the mouth, they perform the function of the organs of touch.

External structure of birds and habitat

Features of the morphological structure of birds in many respects determine the conditions for their dwelling.

A vivid representative of the ratless African ostrich is not capable of flying. Therefore, he has high, powerful legs, on which there are only two fingers. All this contributes to a quick run and makes it the largest bird on the planet. And thanks to the long neck, they can look out for small land animals that feed.

Penguins, despite the presence of the keel, are also not capable of flying. It does not allow them to fly into the air a large fat layer, which is necessary for life in severe northern conditions. This is compensated by their ability to swim perfectly. This is possible due to the fact that the forelimbs are modified into elastic fins. So the penguins are flying in the water.

The life of the representatives of the geese is closely connected with water. That's why they have an elongated body, shortened and shifted back legs. This makes it easier for birds to dive under water for food. Between the toes are swimming membranes. Interesting structure has a beak. In form it is wide and flat, and inside the upper part is a system of horny plates. With their help, swans, mallards and eiders filter out food.

Owls and owls have a hooked beak, powerful and curved claws on their fingers, long wings and a short tail. Such features of the structure allow them to be forest predators. A thick and soft plumage provides a noiseless flight.

Features of the external structure of birds: table

Birds are a group of warm-blooded animals adapted to flight. The table shows the main features of their morphology.

Thus, we can draw the following conclusion. The study of the external structure of birds indicates that its main features make these animals capable of flying.