Bird feathers are cutaneous horn formations. They appeared in these organisms in the process of evolution. Act as fixtures for the flight.
Pen structure
In its structure, two parts are distinguished: the rod, or trunk, and the fan. The lower thickened part of the shaft is called the center. Inside it is a keratinized, dried tissue.
The fan consists of first-order barbs that are attached to the shaft. Also, the structure of the pen provides for the presence of second-order barbs that are attached to the first-order barbs. They are perpendicular to the last. They have special hooks, or cilia, thanks to which all the barbs are tightly fastened together.
Barbs consist of two layers. The external is called horny, and the internal is called cerebral. It is built from dried dead cells with the inclusion of air bubbles. The shape of the feather of a bird and its size can be different, however, the principle of its structure is always the same as described above.
How did feathers appear?
The first animals to have a similar type of skin were predatory dinosaurs, Sinosauropteryx. Fibrous fluff was present on the surface of their body. The first real feathers appeared in caudiperixes and microraptors. The feathers of the birds living now have the same structure as the covers of these ancient animals.
Types of feathers
They can be divided into five main groups:
- coverts;
- fly;
- steering;
- downy;
- special.
Let's look at them in order.
Covering
These bird feathers cover the entire body, giving it a streamlined shape. Depending on the location on the bird’s body, they can be divided into the humeral, cervical, parietal, dorsal, supratail, goiter, pectoral, covering feathers of the abdomen, lower legs, small, medium and large wing covering feathers.
Covering feathers are located throughout the body of the bird in a tiled manner. They perform protective and heat-saving functions, since the layer they form practically does not allow air to pass through.
Fly
These bird feathers can be divided into two groups:
- first order;
- second order.
Feather feathers are long and straight. A great example of this is the quill pen, which was written in ancient times.
First-order flyworms are attached to the back of the bird’s hand. These feathers are the largest. They provide the lifting force and traction during the flight. The number of such feathers is usually 10-15 pieces. So, representatives of the woodpecker family have 10 fly feathers of the first order, ducks - 11-12, and some grebes - as many as 17. An example of how a goose feather looks like:
Second-order feathers attach to the skin on the ulna. They represent the bearing surface of the wing. They are characterized by a smaller size than feathers of the first order.
Their number may also be different. For example, hummingbirds have only six, but some representatives of the albatross family have 37.
Separately, it is worth highlighting the so-called wing. This is a collection of small fly feathers that are attached to the first finger. Their number is usually 3-4, sometimes 6.
Steering
These are the feathers of the tail of a bird. They are similar to flywheels, but more flexible. Also, the steering feathers can be not only straight, but also curved. With their help, the bird changes the direction of flight, moving its tail in different directions. Typically, such feathers are located in one slightly curved transverse row.
Downy
This group can be divided into two subgroups: down feathers and down. Feathers have longer stems than down. However, their barbs do not interlock in the fan. Down has a less developed, soft shaft. Barbs also do not cling to the fan.
Both down and feathers are designed for thermal insulation. They are under the outline. When the chicks only hatch, they possess only fluff, covering feathers grow later.
Special
These feathers include vibrissa, decorating, brush, powder.
Vibrissas are feathers that have lost their beards. They have only the core. They are located at the beak of the bird and perform a tactile function. Also, small beardless feathers can be found on the eyelids and nostrils.
Decorating is a variety of modifications of the contour feathers. They appear during the mating season.
The brush-feathers are feathers with a long thin shaft and grooves, weakly linked to each other. They are usually located around the excretory duct of the coccygeal gland.
Puffs are a kind of special feathers, the beards of which, only growing, break. As a result, a powder forms, covering the other feathers with a thin layer. It is needed to make them waterproof.
What does color depend on?
The feathers of different birds can have the most diverse colors. It all depends on the amount of certain pigments. The color of the feathers is regulated by such substances:
- carotenoids;
- porphyrins;
- melanins.
The pigments of the first group create orange, yellow, red and pink shades. These substances pass into the plumage of a bird from the food that it consumes. If the animal’s diet does not have enough products containing crotinoids, then its plumage may change to gray.
Porphyrins create green shades.
Melanins form brown and black feathers. They can also create some shades of yellow.
In addition, the color of the bird may depend not only on the pigments contained in the feathers, but also on the structure of the first and second order barbs. Depending on how the beards are arranged and arranged, the feathers reflect the sun's rays with different wavelengths. Thus, feathers can shimmer in the sun.
Since the production of many pigments in the body of the bird is regulated by the liver, a discoloration may indicate some diseases, such as chlamydia, vitamin A deficiency, excess zinc, etc.
How do birds care for feathers?
Birds devote about two hours a day to this occupation.
They can clean feathers in many ways. For example, fast-flying birds, such as swallows, swifts, terns, are plunged into the water on the fly. Some wet their feathers in rainwater. Also, birds can take dust baths to care for them.
Remove foreign objects that have fallen into plumage, birds with their beak.
There is also a special tool to give feathers elasticity and eliminate pathogens. This is the fat that is secreted by the coccygeal gland of birds. First, birds put it on their feet, and then rub their paws on their heads.
To disinfect feathers, some birds specifically damage anthills. In this case, formic acid gets on the bird's body. It helps to get rid of microorganisms and other parasites that live in plumage.
Conclusion: record feathers
The longest feathers are found in birds such as decorative Japanese roosters. Their length is more than 5 meters. They are located on the tail.
Argus, a bird similar to a peacock, also boasts long feathers. Two middle feathers on her tail reach 150 cm in length.
Peacocks can rightfully be considered birds with the most beautiful feathers. Their plumage looks colorful due to the special structure of the tail feathers that reflect the light.
Another bird with the most beautiful feathers can be called paradise. Their plumage can be of different colors. And the feathers on the tail can be of the most diverse lengths and shapes. For example, they can be twisted in a spiral shape.