Charting the World : Geography and Maps from Cave Paintings to GPS with 21 Activities (eBook)

Many thousands of years ago, a man stood on a hill, looking down upon the scenery spread before him a hundred feet below. At the far right of his view the terrain was littered with large and small boulders, home to many snakes and lizards but also a good shelter during a stampede. Straight ahead was the vast plain of high grass, dotted with only a few trees and stretching all the way to the high mountains in the far distance. And to the left began a thick forest, which in turn led to a wide river that was home to much wildlife. It was all so easy to see from this vantage point, yet once the man descended the hill, he lost all sense of perspective. Once he set foot into the forest, it was hard to keep track of distance and direction. Once he walked upon the plain, it was difficult to see where he was going. If only he could preserve this image permanently, he thought, if only he could etch the geography that lay below onto something more dependable than his mind. Thus was born the first map. What Is Geography? The word geography is of Greek origin. It comes from the Greek words 'geo,' meaning earth, and 'graphy,' meaning writing or describing. Geography is place. When you set foot outside, you are immediately confronted with geography. Look around. Notice the particular features of your neighborhood. You may live in the heart of a great city, surrounded on all sides by huge skyscrapers. Or perhaps you live in a rural area withnothing in sight except fields. No matter where you live, your geographical location undoubtedly has many unique features, both natural and manmade. The natural features (or landforms) of your location-mountains, hills, plains, deserts, canyons, streams, rivers, lakes, oceans, peninsulas, and islands-are its most basic geographical elements. Topography, the details of the earth's surface features, is closely connected to where people live and how they live. Location and surface features determine climate, which in turn determines a number of other things: the number of people who can live there, the type of crops that can be grown, the types of animals that can live there, and natural resources that can be found. In short, where in the world you live affects howyou live. So how did the geography of the world come to be? What forces have shaped it? Pangaea Each of the earth's physical features was formed in a unique way and at a unique time. Some of the earth's features were formed billions of years ago, some were formed only thousands of years ago, and still others were formed recently. Under a seemingly calm surface, the earth is very restless. Much of the change to the earth's topography has been due to movement of its crust, the surface layer. The earth's crust is not solid and continuous. It is broken into a dozen major pieces, calledplates, that move and shift (called plate tectonics). These motions account for much of the geological unrest on earth, including mountain formation,earthquakes, and volcanic eruptions. The continents as we know them today did not take their current form until fairly recently. One billion years ago, all the land on the earth was massed together in a giant supercontinent. Between 750 and 540 million years ago, it began to split into pieces that drifted apart. But around 470 million years ago, the plates' movements shifted, and some of the land masses began to drift...