As you can see, the wings have a curve in them so that the air flow above the wings has to travel farther than the air under the wing to get to the end of the wing at the same time. This means that the air above the wing moves faster and this reduces the pressure there. As air has a tendency to move to lower pressure areas, an upward force (lift) is created. Of course, speed is a very important factor here. In order to increase the air speed around the curve, birds flap their wings. However, wings and feathers are not all that you need for flying. Basically, everything about the bird anatomy supports flying in one way or another. Their bones are light, their ears have special balancing capabilities and their feet are perfect landing gears. Some birds can (or rather have to) take up to 50 times as much food than a non-flying animal of the same body weight. They have to do this to provide the immense energy that is needed for climbing against gravity.
Albatrosses are among the largest of flying birds. The great albatross can have a wingspan of over 3 meters. With these huge wings, they are very well designed for gliding in the air. They can travel over incredible distances but as the next funny video shows they tend to have some serious difficulties during take-off and landing.
Now, let's take a look at some bird champions and some interesting facts about birds! The fastest bird (and also the fastest animal) is the peregrine falcon, which can reach flying speeds of about 110 km/h. But that's not all. When this bird is diving to catch a prey, it can accelerate to an incredible 300 km/h. The dive can start from the height of 1 km. This feat would be quite useless without actually seeing the prey from such a distance. The falcon's eyesight is also very special. In clean air, it can spot a pigeon from five kilometers. Although it is the most efficient of all the predators, it is endangered because of the use of pesticides.
To tell you the truth, at first I didn't believe the story about the speed of this bird. After watching this video, the whole thing sounds a lot more credible.
The wandering albatross has the largest wingspan of any living bird. Some male birds have a 340 cm wide wingspan. It is such an excellent glider that it can sleep while it flies!
The smallest bird is the bee hummingbird, which lives in Cuba. It is about 5 centimeters long and weighs only 1.8 grams. Hummingbirds flap their wings up to 80 times a second. This enables them to hover in the air and even to fly backwards. No other bird can do this. To provide enough energy for such rapid beating of their wings, these birds typically consume more than their own weight in nectar each day. Watch this video about the flight technique of these little jewels.
The bird with the longest recorded flight is the common tern. A tern that was banded (marked with a little plastic band) in June 1996 in Finland was recaptured alive 16,250 miles away at Rotamah Island, Victoria, Australia in January 1997. It had traveled at a rate of 125 miles a day.
The bird with the largest field of vision is the woodcock. Its eyes are set so far back in its head that it has a 360 degree field of vision, enabling it to see all round and even over the top of its head. If you look at the picture below you can observe the position of the eyes. If it wasn't for the long beak you would think the bird is flying upside down.
The bar-headed goose is one of the world's highest flying birds, having been seen at up to 10175 m. (That is much higher than the peak of Mt. Everest!) It has a slightly larger wing area for its weight than other geese and it is believed this helps the goose to fly high. Studies have found that they breathe more efficiently under low oxygen conditions and are able to reduce heat loss.
See if you can do these exercises about the language content of this entry.
You can read some interesting and useful idioms in connection with the word 'bird' here.
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