Population Concentrations

Human beings are not distributed uniformly across Earth. We can understand how population is distributed by examining two basic properties—concentration (discussed in this section) and density (see below section on Population Density). Geographers identify regions of Earth’s surface where population is clustered and regions where it is sparse.

Two-thirds of the world’s inhabitants are clustered in four regions: East Asia, South Asia, Europe, and Southeast Asia (Figure 2-4). The four population clusters occupy generally low-lying areas, with fertile soil and temperate climate. Most people live near the ocean or near a river with easy access to an ocean, rather than in the interior of major landmasses.

World Population Distribution

What factors explain the clustering of the U.S. population in the eastern half of the country?

In addition to the world’s four most populous clusters, Africa has several concentrations. The two largest are along the west coast between Senegal and Nigeria and along the east coast between Eritrea and South Africa. The largest population concentration in the Western Hemisphere is in the northeastern United States and southeastern Canada.

Human beings avoid clustering in certain physical environments. Relatively few people live in regions that are too dry, too wet, too cold, or too mountainous for activities such as agriculture.

Population Cartogram

Concentration can also be displayed on a cartogram, which depicts the sizes of countries according to population rather than land area, as is the case with most maps (Figure 2-5). When compared to a more typical equal-area map, such as the one shown in Figure 2-4, the population cartogram displays major population clusters as much larger. As you look at maps of population growth and other topics in this and subsequent chapters, pay special attention to Asia and Europe because global patterns are heavily influenced by conditions in these regions, where two-thirds of the world’s people live.

World Cartogram

In a cartogram, countries are displayed by size of population rather than land area. For example, Canada is the world’s second-largest country in land area, so it appears quite large on most maps. But it ranks only 38th in population so it appears small on this map. Conversely, Bangladesh ranks only 92nd in land area but is 8th in population so appears large on the cartogram. Countries with populations over 50 million are labeled.

Ecumene

The areas of Earth that humans consider too harsh for occupancy have diminished over time, whereas the portion of Earth’s surface occupied by permanent human settlement—called the ecumene—has increased

The portion of Earth’s surface occupied by permanent human settlement has increased

By 7,000 years ago, humans had occupied most of Earth’s land (except Antarctica), but permanent settlements existed primarily in Southwest Asia, Eastern Europe, and East Asia.Even 500 years ago much of North America and Asia lay outside the ecumene. Still, approximately three-fourths of the world’s population live on only 5 percent of Earth’s surface. The balance of Earth’s surface consists of oceans (about 71 percent) and less intensively inhabited land.

Pause & Reflect 2.1.2

Why are some land areas not part of the ecumene?