Do birds fly. Why do birds fly? How does lift develop in birds?

When I see birds soaring in the sky, I am always amazed: “How do they manage to stay in the air?”. After all, it is known that there is a force of gravity, which, in theory, should pull them down. Then what is their specialty?

What gives birds the ability to fly

Flying is a complex process. Of course, its main mechanism is the wings. They are arranged in birds in such a way that they are able to create lift, which, in turn, opposes the force of gravity. This force is generated when the wind hits the wing. But what do birds do if there is no wind?

They actively flap their wings, thereby creating a stream of air that lifts them above the ground. This is the most important stage of take-off, thanks to which, having flown up, the bird can soar without making a movement of the wings.

Of course, in addition to the wings, the musculature, the skeleton, and internal organs. To make it easier for the bird to rise into the air, it should be as light as possible. For this reason, her bones are filled with air. Also, a short intestine contributes to the rapid excretion of food, which facilitates the weight of the bird.

Why do birds fly in a wedge

If the reasons for the flight process can still be somehow guessed, then how to explain why most large birds fly like a wedge? It is amazing how synchronously and harmoniously they do it.

As it turned out, they choose such a construction in order to save energy. The first bird sets the air flow, and the subsequent ones, roughly speaking, take advantage of this - they pick up this flow and, thanks to synchronous movements, facilitate their flight.

Which birds don't fly

So, what does a bird need to fly:

• Small body weight.
• Developed muscles.
• Wings and weight must be proportionate.

Not all birds possess all these qualities, and accordingly, they are deprived of the opportunity to fly. For example, penguins and ostriches do not fall under the last paragraph.

There are birds that have ceased to fly in the process of evolution due to the fact that the need has disappeared. They had no one to fly away from, there were no enemies in the surrounding nature. Now they are on the verge of extinction. Among them, for example, the kiwi bird.

Working on the project "Secrets of birds", we decided to find out if all birds fly and why some of the representatives of birds have lost the ability to fly. After watching this presentation, you can get acquainted with flightless birds and find out why they cannot fly.

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Project: “Do all birds fly? Why can't some birds fly? leader: teacher primary school MBOU - Poluzhskaya school Pinchukova Elena Fedorovna. Performers: 3rd grade students

Flightless birds do not have a keel, an outgrowth on the sternum to which powerful muscles are attached that are responsible for flight. All flightless birds have either a very small keel or none at all. For this reason, their wings are weak, and the birds are not capable of flight.

Ostriches are the largest birds living on Earth today. Some of them reach a height of 2.7 meters. Ostriches live in the open plains of Africa. Ostriches feed on seeds, fruits, as well as lizards and insects. Ostriches cannot fly, but they can run fast. At short distances, they can reach speeds of up to 70 km / h.

Emus are large flightless birds living in Australia, they reach a height of 2 m. These birds feed on seeds, fruits and insects.

So why don't ostriches fly? And here's why! They are too big, a bird can fly if its mass does not exceed 20 kg, and ostriches weigh 120 kg.

It is interesting! One ostrich egg is equal to 40 chicken eggs and can support the weight of a person.

Penguins are flightless birds. There are 18 various kinds penguins. They live only on the coasts of the seas of the Southern Hemisphere - on the islands off the coast of Australia, in New Zealand, in South Africa and in the southern part of South America. Penguins are excellent swimmers, they can move through the water at a speed of 30 km/h. Those penguins that live among the snow and ice do not make nests.

The emperor penguin is the largest of the penguins. His height is about 1.2 meters, and his weight is about 75 kg. When the female lays an egg, the male protects it from contact with ice by placing it on his own webbed feet. When the chick hatches, the male, having eaten nothing for two months of incubation, goes in search of food, while the female stays with the chick to feed and protect him.

The jumping penguin is named so due to the fact that it jumps very dexterously from stone to stone. Its most noticeable difference is a long crest on its head. Newly hatched jumping penguin chicks are covered in soft down. They are helpless, and parents have to feed and protect them for several weeks.

The donkey penguin makes a sound similar to the cry of a donkey. It is also known as the black-footed penguin.

King penguins live in Antarctica. They can slide on their belly on ice at high speed to get away from enemies.

Why don't penguins fly? Penguins used to fly, but more often hiding from enemies, hiding under water, and gradually their wings lost their feathers and turned into fins.

But that's not all that these birds can surprise us with. We eat three times a day, and penguins may not eat for up to three months. A person cannot live without air, and penguins can not breathe for almost 18 minutes. How interesting!

Kakapo, or owl parrot, is the only parrot that has forgotten how to fly. He lives only in New Zealand, he had no enemies around him and he did not need to hide or fly away. Kakapo lives in burrows. He spends the whole day in them and only after sunset he leaves from there to go in search of food - plants, seeds and berries.

The little Kiwi bird also lives in New Zealand and is protected by the state. She has no wings at all.

Kiwi is a small and shy nocturnal bird. The kiwi has an excellent sense of smell, and the nostrils are located at the end of its long beak. Kiwis stick their beaks into the ground to find food.

The Tristan shepherd, living on the island of Unapproachable, is the smallest flightless bird in the world. It is only 17 cm long and weighs less than 30 g.

So, let's conclude: there are flightless birds on earth. But why don't they fly? 1. Have a large size and body weight. 2. Due to predators, birds swam more than they flew. 3. There were no predators and there was no need for birds to fly.

On the topic: methodological developments, presentations and notes

Lesson Type: General Educational Objectives: Expand your understanding of wintering birds. Form the concept of wintering birds. Clarify and activate the vocabulary on the topic, learn to answer the question ...

To an extracurricular activity for the Day of Birds. "Miracle Birds"

This presentation was made for Birds Day. It can be applied in the lessons of the world around us in elementary school ....

Target: To acquaint students with the reasons for the diversity of birds.

Tasks:

• students must learn to recognize environmental groups of birds,
• know the reasons for the diversity of birds,
• know the signs of different birds environmental groups,
• be able to find information from different sources,
• be able to summarize the information received and draw conclusions
• be able to work in groups.

Equipment:

• stuffed animals or drawings of birds of different ecological groups,
• electronic laboratory work(Laboratory workshop. Biology grades 6-11. Educational electronic edition.)

Lesson plan.

1. Organizing time.
2. Repetition of previous material.
3. Formulation of the problem.
4. Performing laboratory work.
5. Conclusion.

During the classes

1. Organizational moment.

2. Repetition of the previous material.

The sparrows fluttered onto the fence.
The cat hears the sparrow choir
Only she can’t get sparrows:
I was too lazy to learn how to fly!

V. Bezborodov

List the signs of the class of birds (as a result of a frontal survey, students should name the signs, write them down on the board)

• Body covered with feathers
• Forelimbs modified into wings
• Beak without teeth
• fast digestion
• Lightweight skeleton (bone cavities)
• warm-bloodedness
• Special breathing (air sacs)
• There is a keel

Conclusion: thanks to these adaptations, birds are able to fly.

Do all birds fly the same way?

(messages prepared by students):

• flapping flight
• Gliding flight
• shaving flight

Reasons for this diversity?

(Living in different conditions, adaptation to them.)

Are there flightless birds? (most often students say:

• Ostrich
• Penguin)

By what signs can we determine the ability of a bird to fly?

• Wings (shape, size)
• Plumage (dense, loose)
• The size and weight of the bird

3. Statement of the problem:

Do flightless birds fly?

If you study the signs of a bird, you can determine its ability to fly.

4. Performing laboratory work "Ecological groups of birds".

Based on the results of laboratory work, a table is filled in (work in groups):

The ostrich is a land bird that is unable to fly.

The penguin belongs to aquatic birds, by all indications adapted to flight.

5. CONCLUSION: the penguin is able to “fly”, but in the aquatic environment.

6. Homework: reports of bird orders.

On a hot summer day, high in the sky, you can see a beautiful sight: a bird of prey slowly soaring in circles. Her flight seems to last forever. Only occasionally, out of necessity, does the bird flap its wings.

The force of gravity, which attracts any object to the ground, has an effect on birds. Therefore, the bird, flapping its wings, counteracts this force. Lift is necessary for flight (as was described in the article: how planes fly), but how does it arise in birds?

How is lift generated in birds?

Lift is generated in the wings. The bird's wing is not flat, as it seems at first glance, but has a convex upward shape. Air, in order to get from the leading edge to the fly wings, must make a longer path along the top of the wing than along the inside. The airflow rate on the top side is higher than on the bottom. Lift is generated on the upper side of the wing, and pressure is generated on the lower side. They act vertically upwards against the force of gravity. The lift force, which is the sum of the traction force and the weight of the bird, depends on the size of the individual and the shape of its wing.

Speed ​​also plays an important role in the flow of air around the wing, and at what angle the air enters the leading edge of the wing. If this angle changes, then the lifting force also changes. If the wings are located vertically relative to the air going towards them, then the stream that flows around the wings, the same one that keeps the bird in the air, will disappear and the bird will end up in an air hole. This is how landing happens.