The external structure of birds - features, interesting facts and examples. Skin and their derivatives in birds What are the tarsus fingers and claws covered with?

The skin of birds is thin, dry, and practically devoid of skin glands. The surface layers of cells of the epidermal layer become keratinized. The connective tissue layer of the skin is divided into thin, but quite dense skin itself, in which blood vessels pass, the ends (edges) of contour feathers are strengthened and bundles of smooth muscle fibers are located that change the position of the feathers, and subcutaneous tissue - a loose layer directly adjacent to the trunk muscles; fat reserves are deposited in it. The only skin gland in birds, the coccygeal gland, lies on the caudal vertebrae. It produces a fat-like secretion that is released through the ducts when birds press on the gland with their beaks. Birds lubricate their feathers with this secretion.

The growths of the keratinizing epidermal layer of the skin form the horny cover of the beak - rhamphotheca. Reptilian-type horny scales cover the toes, tarsus, and sometimes part of the tibia. The last phalanges of the toes are covered with horny claws. In the males of some birds (for example, pheasants), a bony outgrowth is formed on the tarsus, covered with a sharp horny sheath - a spur. The feather cover specific to birds is also the horny formations of the epidermal layer of the skin.

consider its structure. Pay attention to the placement of the eyes. Find the auditory recess. Examine the body of the bird, determine its shape. Pay attention to the position of the wings and legs. Study the external structure of the limbs, the sequence of their sections. What are the tarsus and toes covered with? Remember which animals have the same body coverings. Consider the bird’s tail. Write down the names of the different types of feathers located on the wings and tail, count these feathers. Examine the set of feathers. Find a contour pen, study its structure, sketch and label the main parts. Use a magnifying glass to examine the fan. Draw a diagram of its structure. Consider a down feather. Draw and label the names of its parts. List the adaptations for flight that are clearly visible in the external structure of birds. Fill out the results of your observations in a notebook.

Examine the stuffed bird. Find the main parts of the body. Name them. Examine the bird's head. Pay attention to its shape and size. Find the beak, examine its structure. Pay attention to the placement of the eyes. Find the auditory recess. Examine the body of the bird, determine its shape. Pay attention to the position of the wings and legs. Study the external structure of the limbs, the sequence of their sections. What are the tarsus and toes covered with? Remember which animals have the same body coverings. Consider the bird’s tail. Write down the names of the different types of feathers located on the wings and tail, count these feathers. Examine the set of feathers. Find a contour pen, study its structure, sketch and label the main parts. Use a magnifying glass to examine the fan. Draw a diagram of its structure. Consider a down feather. Draw and label the names of its parts. List the adaptations for flight that are clearly visible in the external structure of birds. Fill out the results of your observations in a notebook.

due by tomorrow
Laboratory work in biology 7th grade topic: external structure of a bird. Feather structure
PROGRESS
1) look at the stuffed bird. Find the main parts of the body. Name them
2) examine the bird's head. Pay attention to its shape and size. find the beak, examine its structure, pay attention to the location of the eyes. find the auditory recess
3) examine the body of the bird and determine its shape. pay attention to the position of the wings and legs
4) study the external structure of the limbs and the sequence of their sections. What are the tarsus and toes covered with? remember which animals have the same body coverings
5) look at the tail of the bird, write down the names of different types of feathers located on the wings and tail

• Read more: Beak: sense of smell and taste

Morphology of birds

Morphology usually refers to the external structure of an animal, as opposed to the internal structure, which is usually called anatomical.

The bird's beak consists of the upper and lower jaws (upper beak and underbeak), covered with horny sheaths. Its shape depends on the method of obtaining food characteristic of the species, and therefore makes it possible to judge the feeding habits of the bird. The beak can be long or short, curved up or down, spoon-shaped, serrated or with crossed jaws. In almost all birds, it is worn off at the end from consumption, and its horny cover must be continuously renewed.

Most species have a black beak. However, there are a variety of variations in its color, and in some birds, such as puffins and toucans, this is the brightest part of the body.

Birds' eyes are very large because these animals navigate mainly by sight. The eyeball is mostly hidden under the skin, with only the dark pupil surrounded by a colored iris visible.

In addition to the upper and lower eyelids, birds also have a “third” eyelid – the nictitating membrane. This is a thin, transparent fold of skin that moves over the eye from the side of the beak. The nictitating membrane moisturizes, cleanses and protects the eye, instantly closing it in case of danger of contact with an external object.

The ear openings, located behind and just below the eyes, in most birds are covered with feathers of a special structure, the so-called. ear coverts. They protect the ear canal from foreign objects getting inside, while at the same time not interfering with the propagation of sound waves.

Bird wings can be long or short, rounded or sharp. In some species they are very narrow, while in others they are wide. They can also be concave or flat. As a rule, long narrow wings serve as an adaptation for long flights over the sea. Long, wide and rounded wings are well adapted to soaring in rising currents of air heated near the ground. Short, rounded and concave wings are most convenient for slow flight over fields and among forests, as well as for quickly rising into the air, for example, in times of danger. Pointed flat wings promote rapid flapping and rapid flight.

The tail as a morphological section consists of tail feathers that form its posterior edge, and covert feathers that overlap their bases. The tail feathers are paired, they are located symmetrically on both sides of the tail. The tail can be longer than the rest of the body, but sometimes it is practically absent. Its shape, characteristic of different birds, is determined by the relative length of the various tail feathers and the characteristics of their tips. As a result, the tail can be rectangular, rounded, pointed, forked, etc.

Legs. In most birds, the part of the leg free from feathers (foot) includes the tarsus, fingers and claws. In some species, such as owls, the tarsus and fingers are feathered; in a few others, in particular swifts and hummingbirds, they are covered with soft skin, but usually there is a hard horny covering, which, like all skin, is continuously renewed. This cover can be smooth, but more often it consists of scales or small irregularly shaped plates. In pheasants and turkeys, there is a horny spur on the back of the tarsus, and in the collared hazel grouse, on the sides of the toes there is a rim of horny spines, which falls off in the spring and grows back in the fall to serve as skis in the winter. Most birds have 4 toes on their feet.

Fingers are designed differently depending on the habits of the species and their environment. For grasping branches, climbing, catching prey, carrying food and manipulating it, they are equipped with steeply curved sharp claws. In running and burrowing species, the fingers are thick, and the claws on them are strong, but rather blunt. Waterfowl have webbed toes, like ducks, or leathery blades on the sides, like grebes. In larks and some other open-space singing species, the hind finger is armed with a very long claw.

Other signs. Some birds have a bare head and neck or are covered with very sparse feathers. The skin here is usually brightly colored and forms outgrowths, for example, a ridge on the crown and earrings on the throat. Often, clearly visible bumps are located at the base of the upper jaw. Typically, these features are used for demonstrations or simpler communication signals. In carrion-eating vultures, the bare head and neck are probably an adaptation that allows them to feed on rotting corpses without soiling their feathers in very inconvenient areas of the body.....

Target: Identify the features of the external structure of birds in connection with flight.
Equipment: Stuffed bird, set of feathers (outline, down, down), tweezers, magnifying glass.

Exercise:

1. Examine a stuffed bird. Find the main parts of the body. Name them.

2. Examine the bird's head. Pay attention to its shape and size. Find the beak, examine its structure. Find the eyes, pay attention to their location. Find the auditory recess.

3. Examine the body of the bird. Determine its shape. Determine the location of the wings and legs.

4. Pay attention to the external structure of the limbs. What are the tarsus and toes covered with? Remember which animals have such cover.

5. Examine the bird's tail. Write down the names of the feathers located on the tail and wing, count their number.

6. Examine a set of feathers. Find a contour pen, study its structure, name the main parts. Use a magnifying glass to examine the fan. Draw the structure of the contour pen, sign the names of its main parts.

7. Consider the down feather. Find an opener and a fan. Draw this feather and label the names of its main parts.

8. Based on the external structure, note the adaptations of birds for flight.

Progress:

1. Main parts of the body: head, body.

2. A relatively small head, on which a beak protrudes, formed by bony jaws. Covered with horny sheaths on both sides. There are nostrils on the beak. On the sides of the head there are large eyes; closer to the back of the head, ear recesses are hidden under the feathers, at the bottom of which there are eardrums.

3. The whole body of the bird is adapted for flight. The forelimbs are turned into wings, the body has a streamlined shape.

4. The bird's tarsus and toes are covered with skin scales like those of lizards.

5. The tail feathers are located on the bird's tail. With their help, birds can control the direction of their movement.

6. Contour feathers are located on the wings. The main structure of the feather is the fan and the shaft with the edge. The fan consists of beards of the first and second order.

Conclusion: The bird's body is streamlined, which reduces drag during flight. The flight itself is carried out by wings with contour feathers and a tail with tail feathers.

Laboratory work No. 9 “Structure of the bird’s skeleton” 26.02

Target. Study the structural features of the bird skeleton. Note the features associated with flight.

Equipment: bird skeleton, tweezers.

Progress

1. Examine the skeleton of a bird. Determine the shape of the skull. Consider the bony base of the beak and large eye sockets, the connections of the lower jaw with the skull and the skull with the spine.

2. Consider the parts of the spine. Name them.

3. In the cervical region, pay attention to the structure of the first two vertebrae, the saddle-shaped shape and the movable connection of other vertebrae. Note the significance of this feature in the life of a bird.

4. Find the thoracic spine, pay attention to the fixed connection of the vertebrae. Consider the structure of the sternum and ribs.

5. Name the bones of the girdle and free forelimbs. Pay attention to the bones of the shoulder, forearm, buckle, fingers.

6. Find the belt of the hind limbs. Examine it, paying attention to the strength of the connection between the pelvic bones and the spine. Explain the significance of this structural feature of the skeleton in the life of a bird.

7. Examine the bones of the hind limbs. Name them. Pay attention to the tarsus - the long bone of the foot. Count the number of fingers.

8. Note the fitness features associated with flight in the structure of the bird’s skeleton.

Progress:

1. The skull is quite small with large eye sockets;

2. Sections of the spine: cervical (9-25 vertebrae), thoracic (3-10), lumbar (6 vertebrae), sacral (2 vertebrae), caudal.

3. The first 2 vertebrae – the atlas and epistropheus – provide mobility to the bird’s head.

4. The thoracic vertebrae are fused into a single dorsal bone. The ribs are attached to the thoracic vertebrae. The thoracic vertebrae, ribs, and sternum form the rib cage, which protects the internal organs.

5. Wing skeleton: shoulder, forearm, hand. Part of the bones of the wrist and metacarpus are fused into a buckle. The skeleton of the free hind limb consists of the femur, the bones of the lower leg, fused together, and the foot. Part of the tarsal bones and all the metatarsal bones are fused into the tarsus.

6. The lumbar, sacral and part of the caudal vertebrae form a complex sacrum. It creates support for the hind limbs. The pelvis of birds is open - the pubic bones do not grow together, but diverge widely to the sides. This allows the birds to lay eggs.

7. Bones of the hind limb: femur, tibia, tarsus, phalanges. Birds have 4 toes (rarely 3).

Conclusion: The musculoskeletal system well reflects the adaptation of birds to flight. The skeleton is light and durable. Lightness is ensured by the pneumaticity of the bones, strength by their fusion. In the hand, the bones have fused into a buckle, in the foot - into a tarsus. The largest and strongest flight muscles begin on the keel of the sternum and are attached by tendons to the bones of the wings.

Birds are a class of warm-blooded animals, the distinctive feature of which is the presence of wings. It is these that the forelimbs turned into during evolution. Let's consider the features of the external structure of birds.

general characteristics

The structure of birds is divided into the following parts:

• The head on which the oral cavity is located. The horny coverings that end the jaw form the beak.
• Movable neck.
• Torso.
• Limbs - front and rear.
• A shortened tail, the main purpose of which is steering function.

At the same time, the class is surprisingly diverse, each genus has its own specific features of appearance.

Leather

Let's consider the features of the external structure of birds and their skin. This organ is thin, consists of two layers, covered with down and feathers. A peculiarity of the skin of birds is the absence of sweat glands.

The surface layer of the skin is covered with keratinized cells. Next comes the skin itself, a thin dense tissue to which the bases of the feathers are attached and contains blood vessels and subcutaneous tissue containing fat reserves.

Feathers

Having examined the features of the external structure of birds, we will find out what is specific about their feathers. First of all, feathers are heterogeneous and are divided into:

• Fly feathers.
• Helmsmen.
• Integumentary.

The first two types of feathers are used for flight; they are stiff and large in size. The cover feathers can be downy or contoured; they cover the body of the bird and are small in size and soft.

The composition of the pen is as follows:

• Origin (base).
• Core (absent in down feathers).
• Fan.

The color of feathers is widely varied and depends on the microstructure of the feather and the pigments it contains; it can change throughout the year.

The feathers are elastic due to the fact that the bird processes them with secretions of its only external gland, the coccygeal gland, located near the base of the tail.

Functions of pens

In the external structure of birds, feather cover plays a special role:

• Helps support the body in the air - participates in flight.
• Maintains body temperature.
• Helps camouflage. Thus, the white arctic partridge, due to its color, is practically invisible in the snow, which helps the bird escape from numerous predators.

It is the feathers that create the outline of the bird’s body, its appearance.

Structure of a pigeon

Let us consider in detail the external structure of a bird using the example of a pigeon. Like all other representatives of the class, the pigeon has a head, neck, torso, limbs and tail. We present the characteristics of each part in the form of a table.

This is the appearance of the bird, the structure of the pigeon. The science of ornithology is studying this issue. These researchers are doing important work that helps reveal how some birds differ from others.

Briefly about the internal structure

Let's consider the features of the internal structure of a pigeon:

• Slightly less than 10% of the body's mass is the skeleton. The bird's bones are light but strong. In order for the pigeon to fly, it has a highly developed chest bone. Interestingly, there are as many as 44 vertebrae in a small neck.
• The muscles are located on the abdominal side and are practically absent on the back.
• Light weight is important for flight, so the bird does not have a bladder and has a small liver and stomach.
• The breathing apparatus is complex in design and helps the pigeon adapt to long flights.
• The stomach consists of two sections.
• The kidneys are located near the spine.

The internal structure of the bird is aimed at making flight accessible.

Features of other birds

Let's consider the external and internal structure of birds of various species.

The eagle is distinguished by well-developed muscles, has powerful claws and a curved beak. Due to this structure, the bird is a dangerous predator that can carry even a young artiodactyl into its nest. These birds have a very well developed neck, which compensates for the low mobility of the eyeballs.

The flamingo bird has a very unusual external structure; it has a long, thin neck and long legs. The neck consists of 19 vertebrae, the flamingo's beak is very massive, and its long legs have small toes with blunt claws, three of which are connected by swimming membranes. The tail and wings are short. These beautiful birds with soft plumage can stay on the water for a long time and swim well.

Having examined the features of the bird class and the external structure of birds, we learn some interesting facts from the life of birds:

• Birds do not have teeth, which helps them reduce the mass of their skull and makes flight possible.
• The wingspan of some birds (for example, albatrosses) can be more than 3 meters.

• The approximate number of feathers on swans is more than 25 thousand.
• Once or twice a year, birds molt, completely getting rid of their feathers and acquiring new ones. But due to the fact that the process occurs gradually, most birds do not lose the ability to fly.
• During molting, geese, ducks and swans lose all their primary wings at the same time and are unable to fly for some time.
• Flamingos have amazingly beautiful pink feathers. What causes such an unusual color? Birds eat crustaceans rich in dyes, which is why their plumage acquires a delicate pink tint.

Studying the external structure of birds is not an easy task. Since there are a large number of birds, each species has characteristic features. However, they all have common features, which allowed scientists to unite birds into a single class.