In this activity we will consider the question: What is the right population size for the planet? Is there a “right” size? Many people believe that the earth is overpopulated, but is this true?

Population Clock

Click on the image below to view the current world population at Worldometers.

Look not only at the current world population, but also at the rate at which the world's population is growing. 

With this information, what are your current thoughts (and feelings) about each of the following: 

1. Overpopulation.
2. Sustainability of our resources in relation to our population growth.
3. What is the geographic perspective on growing populations (Social, Political, Economic and Environmental)?
4. What parts of the world are experiencing the greatest or slowest growth?

Our Global Population: Where and how many?

Demography is the study of populations and demographers are the people who undertake those studies. Demographers work to identify and respond to global demographic change: Why is life expectancy in Canada (82 years) so much higher than Swaziland (49 years)? They also investigate national demographic changes (e.g., Canada’s aging population). Once the statistics identify a pattern or a trend, demographers work to describe and explain its causes and consequences.

Demography then, uses statistics including, but not limited to birth rate, death rate, age, sex, and migration. Additionally they use population density (a measure of the number of people living in a square kilometer) and population distribution (where the population is located).

What population pattern is evident on the following map? What social, political, environmental or economic issue(s) could explain the pattern you identified?

World Population Density (people/km2)

Wikipedia

Population Theories

This Khan Academy video explains the population theory of Reverend Thomas Malthus, an English economist. Malthus is credited with being the first person to author and publish an essay dealing with population growth in relation to food supply. He went on to suggest that war, disease and famine were the natural “limits” to population growth. These “Malthusian checks” would help keep the population low enough for the available food supply.

More recently (1982) William Catton published his ideas about population growth.

Mayfield Geography Department
Long Description

Theories of Malthus and Catton

Use the following organizer to summarize in your own words and record your thinking about the theories of Malthus and Catton.  

In one lens enter the attributes and important points of the Malthusian Theory on Population. In the other lens area list attributes and the most important details about Catton’s Theory on Population. In the nosepiece area answer the question: How do I see the future of the world’s population?

You will need to be succinct. Use the two maps below to help you arrive at your opinion.

What do they say to you about the current paradigm that suggests that the earth is overpopulated? Is the earth overpopulated for the resources we have?  If you are uncertain at this time, pose two or three questions and explain how they would help clarify your thinking about overpopulation.

Global Status of Human-Induced Soil Degradation

Mapping the World's Degraded Lands

Global Status of Unmanaged Freshwater

Safe Seas

Overpopulated: Myth or Fact?

Many people believe the earth is overpopulated, but if we look a bit deeper we may find that the earth is, in places, over-crowded, not over-populated. In fact many think that the idea of the world being overpopulated is a dangerous myth. When our global population surpassed the 7 billion mark, it was certainly reason to stop and consider the implications of a population of this size.

View the following three videos. Are your criteria to measure overpopulation used in any of these video clips? If we have sufficient amounts of food, water and shelter, perhaps we are not overpopulated at all? When we perpetuate this world view, we neglect to address other real issues: forced population control, food distribution, human rights abuses and many others. 

Demographic Transition Model

We can identify some patterns and trends that populations around the world seem to go through. The Demographic Transition Model (DTM) is the most widely used tool that illustrates the typical changes populations have made as they experience economic or industrial development.  

Population Pyramids

Population pyramids are useful because they allow us to compare countries, and help to forecast future trends. For example, in Canada our growing elderly population may mean more retirement and seniors facilities are needed. On the other hand, an increase in younger people, as seen in our Indigenous communities may mean more schools are required.

In general, population pyramids show:

• The population of a country or region divided into five-year age groups.
• The percentage of people in each of these age groups.
• The percentage of males and females in each age group.
• Changes in birth and death rate, life expectancy and infant mortality.
• The proportion of elderly and young people who are dependent upon those of a working age - known as the economically active.
• The effects of people migrating into or out of the country or region.
• The effects of government policies e.g., China's one child policy.

Animated population pyramids help to visualize changing populations. This TED talk, Population Pyramids: Powerful Predictors of the Future, illustrates the power of the population pyramid.

Quality of Life for all?

What most people care about is not represented in the numbers or the maps, but the quality of life that people experience and hopefully enjoy. We can use the population theories, Demographic Transition Model and population pyramids to determine our quality of life and also the impact that population changes have on our natural environment. Really, we can better understand our sustainability through population studies.

When we use the term “quality of life” we are referring to the general well being of individuals and societies, including not only wealth and employment but also the environment, physical and mental health, education, recreations, leisure time and social belonging.  You can see that the notion of quality of life would change from place to place and from person to person.

When it comes to quality of life, what matters to you?

Demographer Hans Rosling uses simple Ikea boxes to illustrate the role improved living standards and quality of life, especially for the poorest, will play in limiting our global population growth.

What is the “right” size of population for the world? Is the earth overpopulated, or in places is it overcrowded?