Are the basic characteristics of a bird feathers or ? It s best to write a reason.

The main characteristics of birds are: most of them fly life. The surface of the body is covered with feathers, the forelimbs generally become wings (some species of wings are vestigial), the bones are porous, and the interior is filled with gas; The heart has two atria and two ventricles.

Constant body temperature. In addition to the lungs, the respiratory organs also have air sacs formed by protruding from the lung walls to help the lungs breathe twice. Oviparous.

Birds are bipedal, homeothermic, oviparous vertebrates covered in feathers, with forelimbs that evolved into wings and a hard beak. Birds range in size from very small hummingbirds to giant ostriches and emus (a large, flightless bird native to Australia).

There are many species of birds, distributed all over the world, and the ecology is diverse, and birds can now be divided into three general orders. The flat-chested general order includes a class of birds that are good at walking but cannot fly, such as ostriches. The general order of penguins includes a group of birds that swim and dive but cannot fly, such as penguins.

The vast majority of birds belong to this order, including birds with well-developed wings and capable of flying.

There are more than 9,000 species of birds known to the world, and more than 1,300 species have been recorded in China alone, many of which are endemic to China (see List of Endemic Bird Species in China). There are about 120-130 species of birds that are extinct, and birds are a species with many unique physiological characteristics compared to other terrestrial vertebrates.

Birds eat a variety of foods, including nectar, seeds, insects, fish, carrion, or other birds. Most birds are active during the day, but some birds (such as owls) are active at night or at dusk. Many birds make long migrations in search of the best habitat (e.g. Arctic terns), while others spend most of their time at sea (e.g. albatrosses).

Most birds can fly, and a few flat-chested birds can't, especially those that live on islands, and basically lose the ability to fly. Flightless birds include penguins, ostriches, kiwis (a wingless bird native to New Zealand), and the extinct dodo. When humans or other mammals invade their habitats, these flightless birds are more vulnerable to extinction, such as the great puffin, and the New Zealand moa.

It has to be alive, and if it doesn't die, it can't fly even if it has feathers.

It's a feather, and it can't fly without feathers, and how can it be called a bird if it can't fly. Of course, there are some special birds, such as ostriches.

Feathers on a bird's body provide flight, warmth, body protection, and protection from rain.

Feathers are a unique attribute of avians, which slowly transform from cells to feathers during the evolution of birds, providing an important guarantee function for birds.

Overall: lightweight, waterproof, warm and colorful.

Feathers are keratinized products derived from avian epidermal cells. Covered on the surface of the body, it is light and tough, slightly elastic, waterproof, and has the functions of body protection, heat preservation, and flying. There is a void in the middle to reduce the mass of the feathers.

Lightweight, tough, elastic and warm. The processed and selected feathers are clean and shiny, and have high economic value.

According to the structure, feathers can be divided into three categories: regular feathers, down feathers and fiber feathers. The main feather, also known as the feather, is large, hard and straight in shape, and consists of a feather shaft and a feather piece (or armor feather). It can be divided into fly feathers and tail feathers, which are the materials for making feather fans; Some birds, such as pheasants and peacocks, have colorful tail feathers that are often used as ornaments for crowns.

Down feathers, also known as brocade feathers, are born under the main feathers of adult birds, with the chest and abdomen as the most, slender, flexible, warm, is a good bedding material for making pillows, quilts and clothes, especially goose down and duck down are better. Feathers, also known as hairy feathers, are found at the edge of the eyes, at the base of the beak, and between the feathers and down feathers.

There are three types of feathers in birds: regular feathers, down feathers, and hairy feathers. The feather branches of the main feather are densely feathered, and there are hooks or grooves on the feather branches, and the adjacent feather feathers are hooked to each other to form flat and elastic feathers. The positive feathers on the body surface form a windproof shell and give the bird a streamlined profile.

The structure of down feathers is characterized by the delicate shaft and the underdeveloped hook-like protrusions of the feather feathers, so they cannot form a solid feather. The main feather is a type of bird feather that consists of a feather shaft and a feather petal, and many feather petals are born on the feather shaft. The secondary feather is another type of bird feather, also called "hind feather", which is born at the base of the main feather, and is generally a cluster of scattered small feathers.

Down feathers are born on the body surface of young chicks and the base of the main feathers of adult birds, also known as cotton feathers, commonly known as down, which is a kind of bird feathers. Born at the base of the main feathers of adult birds or on the body surface of chicks. The feather trunk is degraded, and the feather branches are soft and clumped; The feather twigs are slender, unhooked, shaped like cotton wool, fluffy, and not petal-shaped.

It has a strong thermal insulation ability.

1, Zhengyu.

The main feather is a large feather covered in the body, consisting of a feather shaft and a feather piece. The part of the lower part of the feather shaft without feathers is called the feather root, which is born in the **. The two sides of the upper section of the feather shaft send out many feather branches, and each feather branch sends out many feather branches to both sides, and there are small hooks on one side of the feather branches, and there is a groove on one side of the feather branches, so that the adjacent feather branches are knotted with each other to form a tight and elastic feather piece.

The positive feather has the functions of flying, protecting the body, and keeping warm.

2. Down feathers. The down feathers are densely grown under the main feathers, and the feathers are slender and filamentous, and they are born at the top of the feathers. The feather branches are short, and the top is clustered with filamentous branches, and the feather branches have no hooks, no feather branches or fine hooks, and cannot be connected into feathers, so the feathers are fluffy and downy. Waterfowl down feathers are more developed, and duck down is this kind of feather.

The down feathers covered on the body surface of the chicks after breaking the shell are called chick feathers, and the down feathers have the effect of keeping warm.

3. Half down feathers.

Semi-down feathers are a type of feather that is between a down feather and a regular feather, which has the structure of a regular feather but lacks a feather hook and flange, so it is fluffy like a down feather. It is generally distributed under the main feather. It has the effect of thermal insulation.

4. Fiber feathers. The feathers, also known as "hairy feathers", are scattered between the main feathers and the down feathers, with only a slender feather trunk, hairy, and a few feathery branches and feathered twigs at the top. The basic function of hairiness is the sense of touch.

5. Powder powder is a specialized down feather, which grows for life without shedding, and the feather branches and feather twigs at the end are constantly broken into powdery particles, which helps to remove the dirt on the main feather or make the feather waterproof. The heron has a well-developed meal, and is distributed in patches on the thorax, abdomen and flank. The pink feathers of eagles and parrots are distributed throughout the body.

Flying and having feathers are not essential characteristics of birds. Feathers are derivative of the epidermis of birds, although the most basic appearance characteristics of birds in general: the body is basically covered with feathers, but not all feathers belong to birds.

For example, some theropod dinosaurs also had feathers, such as Heclidosaurus, Beipiosaurus, Sinosaurus and some dinosaurs of the family Chiosauridae.

In addition, there are many species that can fly even if they are not birds, such as: bats, dragonflies, butterflies, bees, butterflies, moths, beetles, fireflies, bees, mosquitoes, flies, cicadas, beetles, praying mantises, locusts, longhorn beetles, weevils, orange-footed flying squirrels, hairy-eared flying squirrels, compound toothed flying squirrels, flying squirrels, flying gliders, etc.

In addition, chickens, ducks, geese, and other poultry can also make short flights.

The role of bird feathers1. The feathers of birds form a thermal insulation layer on the body surface to maintain body temperature.

2. The feather itself can protect**.

3. Feathers are an important structure for birds to complete flight.

4. Some parts of the feathers have a tactile function.

5. Bird feathers are light and hard, elastic and waterproof.

6. The color and markings of the feathers play the role of protective color.

Flying and having feathers are essential characteristics of birds. The structural features of birds are always adapted to their lives. If the forelimbs become wings, there are large regular feathers, arranged in a fan-shaped, suitable for flight; The body is streamlined, which can reduce drag when flying; There are air sacs in the body to assist the lungs to complete double breathing and can supply sufficient oxygen; Some bones are hollow, some bones are healed, and the rectum is very short, which can reduce weight; The pectoral muscles are well developed, which is conducive to pulling the wings to complete the flight action.

It has a large amount of food and strong digestion ability, which can provide sufficient nutrients for the flight.

Therefore, the answer is: the forelimbs become wings, with large regular feathers, arranged in a fan-shaped, suitable for flight; The body is streamlined, which can reduce drag when flying; There are air sacs in the body to assist the lungs to complete double breathing, which can be clearly buttoned to supply sufficient oxygen; Some bones are hollow, some bones are healed, and the rectum is very short, which can reduce weight; It has a large amount of food, strong digestion ability, and can provide sufficient food for the flight; The pectoral muscles are well developed, which is conducive to pulling the wings to complete the flight action.

The structural characteristics of the bird are: beak and toothless; The forelimbs become wings; The body surface is covered with feathers, which has the effect of heat preservation; The body is streamlined, which can reduce drag when flying; Double breathing, which can supply sufficient oxygen; Some bones are hollow, some are healed; The rectum is short and allows for weight loss. It is these characteristics that are suitable for the bird's empty life in the forest.

The body of a bird is covered with feathers, and its forelimbs become wings, which are its flight organs.

Wings, organs used by animals such as birds and insects to fly.

A bird's wings are the basic structure of flight. The wings are covered with hard feathers, which are suitable for flight. The shape of the wings is determined by the feathers, which enable the bird to fly.

As the feathers flap downward, the air under their wings creates a driving force called drag. And due to the different sizes of the flight feather feathers, the resistance on both sides of the feathers is also different.

There are four types of wings for flying birds. Birds with high take-off velocities have half-moon-shaped wings, such as pheasants, woodpeckers, and some other birds that are accustomed to being active in smaller flight spaces. The wings of these birds also have some small space between their feathers, allowing them to reduce their weight and facilitate quick movement.

But such wings are not suitable for long flights.

Brown swifts, swifts, and birds of prey have longer, narrower, and pointed wings with no gaps between their main feathers. The more "thick" wings will be reversed backwards, similar to the wings of an airplane, and can fly at high speeds.

The other two types of wings are "gliding" wings and "lifting" wings, which are similar in appearance but different in function. Gliding wings are represented by seabirds, such as seagulls, etc., with longer, narrower, and flatter wings, and there are no gaps between the feathers. During a gliding flight, the bird does not flap its wings, but glides with the air currents, which allows the wings to rest.

As it glides, the bird will fall lower and lower down until it has to start vibrating its wings to stay in the air. At other times, gliding-winged birds fly high for hours on the hot air current.

The rising wing structure is represented by eagles, cranes, and vultures. Unlike gliding wings, there is a wide space between the feathers of a rising wing, which is shorter, which allows for changes in air flow; The feathers are wider, allowing the bird to carry its prey. In addition, these feathers also help to increase the speed of air flow on the upper side of the wings.

When the bird rolls up the tips of its feathers, it adds power to flight without the need to flap its wings. In this way, the bird can take advantage of the air currents around it to rise effortlessly. Rising birds also have relatively wide flight feathers, which greatly increase the area of their wings and allow them to soar more easily over hot air currents.

While rising and gliding, the bird will take full advantage of the updraft to rise. These air currents allow the bird to "stay" on the upward column of air flow. Many birds have discovered this updraft and used it to maintain an extraordinary upward movement.

Many birds stay on the ground at 9 to 10 a.m., waiting for this updraft to appear.

The structural features of birds are always adapted to their lives, such as the forelimbs become wings, with large regular feathers, arranged in a fan shape, suitable for flight; The body is streamlined, which can reduce drag when flying; There are air sacs in the body to assist the lungs to complete double breathing and can supply sufficient oxygen; Some bones are hollow, some bones are healed, and the rectum is very short, which can reduce weight; The pectoral muscles are well developed, which is conducive to pulling the wings to complete the flight maneuver Large appetite and strong digestion ability, which can provide sufficient nutrients for the flight

Answer: (1) The body shape of birds is streamlined, which can reduce the resistance of the air to them during flight and adapt to flight life

2) The whole body of birds is covered with feathers except for the feet, and the feathers are mainly divided into regular feathers and down feathers The main feathers cover the surface of the body, forming a windproof shell, and can make the body streamlined, and the largest positive feathers are distributed in the wings and tail, which is conducive to the flight of the domestic pigeon and the balance of the body

3) The forelimbs of birds have evolved into wings, and there are large regular feathers arranged in a fan shape, which is conducive to fanning the air to complete flight

4) Some of the bones of domestic pigeons are very thin, some are healed together, and the longer bones are hollow and filled with air, which not only increases the firmness of the bones, but also helps to reduce weight and is suitable for flying life

5) The flight of the domestic pigeon needs to consume a lot of energy, so it is necessary to continuously ingest food from the outside world to supplement nutrition to adapt to this, the domestic pigeon has a large amount of food, strong digestion ability, and supplements the nutrients consumed in the flight; The mouth has no teeth and the rectum is very short, which is conducive to weight loss and is suitable for flight life (6) The air sacs of birds communicate with the lungs, and their main function is to store air and assist breathing, even if the inhaled air passes through the lungs twice, to ensure that the lungs fully carry out gas exchange, assist the lungs to complete double breathing, and provide sufficient oxygen for flight