Geography of Population

• At what geography scale is this map?
• What other information does the map contain? (hint: click a country)

• Examine the World Population Choropleth for another representation of the data.
• Examine the dot density layer and its bookmarks.

Most Populous Countries (Retrieved January 2021)

According to current data from  Index Mundi  , in terms of total population Pakistan and Nigeria have surpassed Brazil.

• Which countries have rapidly growing populations?
• What data do demographers use to make predictions?

GIS maps are composed of layers. By changing the layers we will investigate a the following variables: total fertility, infant mortality, birth rates and death rates and the population growth rate. Turn the layers on and off by using the stack of papers in the upper right.

Average number of children per child-bearing age women. Replacement level is at 2.1 children per woman.

• What spatial pattern do you observe?
• Examine the pop-ups, how have fertility rates changed over time?
• Examine the infant mortality layer. What spatial patterns do you observe?
• To what extent does high infant mortality have a spatial association with high fertility?
• Filter (1st from left) for various infant mortality rates. What spatial patterns do you observe?

Basic Demographic Data

• birth rate per 1,000
• death rate per 1,000
• net growth rate = birth rate - death rate

Resulting in

• positive growth rate
• zero population growth (ZPG)
• negative growth rate

• With a growth rate of 2% a country's population will double in 35 years. At 3% a country's population will double in 25 year. Both rates are within a span of a lifetime.

We will investigate birth and death rates and the growth rate variables in the app map below layers. (Be sure to turn on the appropriate layers)

• What patterns do you observe?
• Where are the countries with the highest birth rates located?
• Filter (2nd from left) to find the countries in which death rates were higher than birth rates in 2017.
• In which countries is the birth rate lower than the death rate? Why does it matter?
• Filter (last on right) to find the countries with a growth rate over 3. What are the implications?

Compare the two maps, birth rate and annual percent growth rate. What relationship do you observe between birth rates and population growth rates?

Explanation from the Population Reference Bureau on the reasons why a population continues to grow even after replacement fertility level has been reached.

How does age structure affect population growth?

A model that shows age cohorts by sex, and each cohort's relative proportion of the country's population. Compare the population pyramids.

• How are they alike and different?
• Which country has the highest portion of its female population in their reproductive years?
• Which country is likely to have the slowest population growth?

The dependency ratio, shows the percent of a country's population that are supported by the country's labor force. Source of these data are the CIA World Factbook.

• Total dependency ratio : 88.8%
• Youth dependency: 75.3%
• Elderly dependency ratio: 4.8%

• Total dependency ratio: 39.3%
• Youth dependency: 17.5%
• Elderly dependency ratio: 22%

• Total dependency ratio: 55.4%.
• Youth dependency: 21.7%
• Elderly dependency ratio: 33.7%.

Life Expectancy should never be inferred from a population pyramid.

How could like expectancy affect population growth?

Each of the stages of the demographic transition model show the effects of variance in birth and death rates over time. What effect did those variances have on population growth?.

• Stage 1: birth and death rates are both high
• Stage 2: death rate declines, but birth rate remains high.
• Stage 3: the birth rates begin a steady decline and the death rate remains stable.
• Stage 4: birth rate and death rates are equal.
• Stage 5: death rate fluctuates, often higher than birth rate.

Countries go through the demographic transition at different times.

In 1798 Malthus published An Essay on the Principle of Population. He examined the relationship between food supply and population growth. He observed the population growth increased exponentially whereas food supply would continue to increase arithmetically. Therefore, starvation was likely and population growth should be slowed."

The power of population is indefinitely greater than the power of the earth to produce subsistence for man" An Essay on the Principle of Population, p. 13.

Jonathan Swift anonymously published his essay in 1729. It provided a satirical solution to the starving poor in Ireland.

"A young healthy child well nursed, is, at a year old, most delicious nourishing and wholesome food, whether stewed, roasted, baked, or boiled; and I make no doubt that it will equally serve in a fricasse, or a ragout." from A Modest Proposal.

Examine the demographic data provided in the table below. Keep in mind the table may contain extraneous data.

• What do you observe?
• What generalizations can you make?
• What data would be useful in determining which country has the fastest growing population?
• Which country is the most likely to experience population momentum? (the population continues to grow even though the birth rate and fertility rates decrease)
• Which country is most likely to face a decline in total population? Why?