Birds are some of the most fascinating creatures on the earth and our interest and fascination in them goes back centuries. Our primary fascination with them is that, aside from insects, they are one of the few creatures that have mastery of the air and can take off and travel to wherever they please. But, various species of birds have other fascinating traits as well.
One example is the albatross. Most birds, in order to stay afloat in the air, have to constantly flap their wings. This, as you might expect, burns a great deal of energy. The albatross, however, is one of the few exceptions. It is an ocean bird and spends most of its time above the open ocean searching for food. The air above the ocean is unique in that the wind is blowing constantly. The albatross has learned to take advantage of these wind currents and ride them expertly. It can effortlessly control its direction by changing from one wind current to another. And it can do all this for hours, without a single beat of its wings - thus expending no energy. It is the ultimate wind surfer.
A second example is the hummingbird. When you ask someone to name an animal that hibernates, the first animal that comes to the mind of most people is bears. Hardly anyone will mention the hummingbird. Throughout the day, the hummingbird expends a great deal of energy in its constant search for nectar. Even while resting, its heartbeat has been measured at anywhere from 250 to 480 beats a minute. In fact, it uses so much energy during the day, that at night, in order to let its body recover and prepare for the next day, it shuts down its body almost totally. In effect, it is hibernating.
Birdwatchers have often wondered how birds are able to migrate back and forth from the same areas year after year. Based on research, it appears to be that they can sense the magnetic field of the earth. Researchers have proven this by taking a group of birds and equipping half of them with magnetic rods that interfere with the earth's magnetism. The others were equipped with non-magnetic rods. The ones with the magnetic rods got lost. The birds equipped with the non-magnetic rods found their destination as usual. In a sense, it seems that many birds that their own built-in, internal GPS system that is dependent on the earths magnetic poles.
With these facts only scratching the surface of interesting bird traits, it is no wonder that some bird watchers spend decades studying their favorite creatures.
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