Geographic distribution refers to the way that something is distributed over a geographical area and can be represented on a map. Geographical distribution is commonly used to demonstrate the spread of animal species and plants around the world. However, it can also be used to show the distribution of virtually anything on a map, including disease, pollution and unemployment.
Some distributions can be seen visually without a map. For example, one can see the distribution of houses and green spaces in a city from a tall building or an airplane. Similarly, the distribution of forests, deserts, and water can be seen directly from space or satellite imagery. For most things, geographical distribution is represented on maps overlaid with data.
Geographic distribution can be indicative of interrelated phenomena. For instance, malaria occurs mainly in tropical areas of the world. This is related to the climate in these areas, where the hot and humid conditions are favorable for the mosquitoes that carry the disease to reproduce and thrive. As a result, the geographical distribution of human infections of the disease is most concentrated in tropical areas of the world, and is sparse or nonexistent in non-tropical areas.
Distribution is equally important in economics, since geographical features often influence patterns of economic activity. In developing countries like China, there is a big difference between rural areas, where most people live off of farming, and large cities, where people work in higher paying jobs in industry and commerce. A map of the distribution of income of China would show this difference and help explain why urban areas have a higher population density than rural ones.