Demography:
Population Studies
Chapter 2
Lesson
Aims:
- Where in the World do People Live and Why
- Why do populations rise or fall in places?
- Why does population composition matter?
- How do governments affect population
change?
Population Stats Challenge
With a partner, try to list the top ten highest country
populations in the world. Please place in rank order:
Source: http://www.internetworldstats.com/stats8.htm
Population Stats Challenge
Now try to list the top ten highest city
populations in the world. Please place in rank order:
There are actually a couple of ways you can
define a city (by including suburbs or just the city
proper), and therefore more than one list.
How do we measure
Population?
Population Density – measure
of total population relative
to land size (arithmetic
population density).
Which are the most densely
populated countries?
What about the least?
World Population Density
What inquiry questions could
you ask about this map?
Physiologic Population Density –
number of people per unit area of agriculturally
productive land (takes this map into account).
What inquiry
questions could you
ask about this map?
Population Distribution –
Descriptions of locations on the Earth’s surface where
individuals or groups (depending on the scale) live.
What inquiry
Dot Map of World Population – questions could you
On this map, one dot represents 100,000 people ask about this map?
Why do Populations Rise or Fall
in Particular Places?
A Population Bomb?
 Malthus (early 1800s) worried about population
growing exponentially and resources growing
linearly.
 Ehrlich (1960s) warned of a population bomb
because the world’s population was outpacing
food production.
The Demographic Transition
in Great Britain
 Studied the change in birth rates, death rates,
and natural growth rates over the course of British
industrialization.
 Found a transition occurred when death rates
decline and then birth rates decline, resulting in a
low or sustained growth rate.
The Demographic Transition Model
The Demographic Transition
 Stage 1: Low Growth (pre-industrial)
 Stage 2: High Growth
 Stage 3: Moderate Growth
 Stage 4: Low Growth or Stationary
 Stage 5: Stationary population level (SPL)?
 Stage 6: A rebound? With high HDI?
Study the Stages of the DTM worksheet and try to match the
stages to countries today
Application of the
DTM?
Activity: try the DTM Living Graph
activity
Limitations of the DTM
•
DTM has a questionable applicability to less economically developed
countries (LEDCs), where wealth and information access are limited.
• DTM assumes that population changes are induced by industrial
changes and increased wealth, without taking into account the role of
social change in determining birth rates, e.g., the education of
women.
What inquiry
World Birth Rate –
questions could you
number of births in a year per 1,000 people. ask about this map?
What inquiry
World Mortality Rate –
questions could you
number of deaths in a year per 1,000 people. ask about this map?
Why does Population
Composition Matter?
Population Composition
Population Composition is concerned with:
Sex distribution
Age distribution
Both within a country, region,
or place.
Population Pyramids –
Charts that show the percentages of each age group in the
total population, divided by gender.
For poorer countries, the chart is shaped like a pyramid.
Infant mortality rates are high, life expectancy is shorter.
Affect of AIDS on
population pyramid for
South Africa.
Predicted population for 2035,
without and with AIDS.
With AIDS, looks like a
population “chimney.”
What are the consequences
for family structures if AIDS
prevails in South Africa?
Population Pyramids –
For wealthier countries, the chart is shaped like a lopsided
vase. Population is aging, TFRs are declining.
Population Pyramids –
Analyzing population pyramids
What can a population pyramid tell us about a population?
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•
•
•
It gives us information about birth and death rates as well as life expectancy.
A population pyramid tells us how many dependents there are. There are two
groups of dependents; young dependents (aged below 15) and elderly dependents
(aged over 65).
Dependents rely upon the economically active for economic support.
Many LEDCs have a high number of young dependents, whilst many MEDCs have
a growing number of elderly dependents.
How do pyramids change over time?
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•
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A triangular pyramid shows a population with a high number of young dependents
and a low life expectancy.
A population pyramid that has fairly straight sides shows a population with a falling
birth rate and a rising life expectancy.
Over time, as a country develops, the shape changes from triangular to barrel-like.
Places with an ageing population and a very low birth rate would have a structure
that looks like an upside-down pyramid.
Population Pyramid Activity
Compare the two population pyramids below:
UK, 2000
Mozambique, 2000
1. What stage are these countries at in the DTM and why?
2. What challenges and/or opportunities may each country face based on
this information?
Population Pyramid Activity
Now compare these population pyramids below:
UK, 2025
Mozambique, 2025
1. What stages are these countries predicted to be at in the DTM and why?
2. What has changed since the year 2000?
3. Are the challenges and/or opportunities faced by each country still the
same?
Aging Populations
 To replace the population, Total Fertility Rate
(TFR) must be 2.1. Some places are far from this
figure e.g. TFR in Bologna, Italy is 0.8
Discussion Questions
So, why are some populations ageing?
What are the impacts of an aging population on a
country?
What are the “solutions” to an aging population?
Government Population
Policies
 Expansive Population Policies
- Encourages population growth, with large families
- Used in communist societies in the past (China, Soviet Union)
- Used today to combat ageing populations (France)
ttp://www.sfgate.com/news/article/European-nations-offer-incentives-to-have-kids3201278.php
 Eugenic Population Policies
- Favors one racial or cultural sector over others. (Nazi Germany, 1960s US)
 Restrictive Population Policies
- range from toleration of unapproved birth control to outright prohibition of large
families (China today)
China’s One Child Policy
What are some of the limitations, unintended consequences, and
contradictions found in government policies toward population growth?