GED Social Studies Practice Test: Demographics
Physical vs. Human Geography
Physical geography deals with the analysis of the Earth’s natural resources and phenomena. Why does Region A have such a heavy rainfall? Why is Region B rich in natural resources?
Human geography is the study of spatial analysis of humans on the planet and their interactions with it — the how and the why of things. Why is much of Europe Christian, while much of the Middle East is Muslim? Why do groups of languages seem to be associated with different places?
Demographics. This is the study of human populations. Geographers use demographics to understand the spatial distribution — which is usually uneven — of people and their movements. It seems pretty obvious that a country’s well-being is affected by the size, composition, and growth (or shrinkage) of its population. For example, the median age of people in Japan is getting older, as people are having fewer children. In China, to slow the growth of the population, the government has implemented a “one-child” policy.
The distribution of people across the world is not even. For example, Asia has many more people than North and South America. In the United States, the smallest state in area (Rhode Island) has one of the highest population densities. It is also important to remember that people can only live where the land is arable (capable of being cultivated) and there is a source of water. Thus, 75% of the world’s population lives on about 5% of the Earth’s surface. About one-half of all people live in cities, while the other half live on farms, or in the desert, or are nomadic. Urbanization is a relatively modern phenomenon that was spurred on by the Industrial Revolution in the 1800s, when people flocked from rural to modern areas in order to work. Carrying capacity is the number of people the area can actually support. Carrying capacity depends on the level of agriculture, technology, and the amount of infrastructure (roads, bridges, water carrying capacity and the like). When a place or a nation’s population exceeds the carrying capacity, you have overpopulation, and the quality of life is almost certain to erode.
The population estimate at any given time point starts with a population base (the last decennial census or the previous point in the time series), adds births, subtract deaths, and add net migration (both international and domestic).
Another aspect of demographics is looking at who works, or is capable of working. We call this the dependency ratio. Of course, not everyone capable of working does work, but looking at the numbers of people in (and out of) the workforce can yield valuable insight. People are considered non-dependent if they can support themselves, and the age range of this group is usually considered to be 15 to 64. Of course, in some nations, there is child labor, and not all 64-year-olds retire. But those who are dependent cannot work, are too young to work, or too old to work, and are supported by others (usually family members, but sometimes a society — think of Social Security).
In places and nations where there are fewer economic opportunities, you have a two-fold problem: there are not enough non-dependents bringing in money to support the dependent population, and eligible non-dependents often feel frustrated and angry that they cannot find work. Since a nation or region needs taxes in order to run social service programs and care for infrastructure, a population with a large dependent population is a society at risk.
Trends in Population Growth
The population explosion over the past several centuries has led to a global population of approximately 7 billion people (remember, over 2 billion people live in India and China alone). Population growth today is exponential: the more people there are, the faster the population grows (in contrast to arithmetic growth, in which the population grows at a fixed rate). In the mid 1700s, the Earth had about 700 million people. Why has the human population grown so quickly? Here are a few reasons:
- Improved agricultural techniques (the Second Agricultural Revolution and the Green Revolution, which introduced high-yield, low maintenance crops).
- Improved health has led to longer lifespans.
- Safer childbirth.
- Vaccines and public health measures.
How many people will the planet have in coming decades? No one can be sure. Some models suggest that the population will shrink (in part due to low birthrates, famine, and disease). Other models suggest that the population could swell to 11 billion by the middle of the 21st century, placing a tremendous strain on available resources.