Hanel, Germany

J. Gathorpe-Hardy

What do you think these cartoons are saying?

Population Change

Births

Immigrants

Deaths

Emigrants

TotalPopulation

Natural Increase

Migration

The total population of an area is the balance between 2 forces of change: natural increase and migration

Natural increase is the balance between birth rates and death rates

Inputs Outputs

World Population Changes

Global Natural Increase

Doubling TimeThis map shows how long it will take for countries to double

their population if it continued to grow at the present rate

Demographic Transition Model

Stage 1 Stage 2 Stage 3 Stage 4

Total Population

Birth RateDeath Rate

Birth Rate

NaturalIncreaseIn Population

NaturalDecreaseIn Population

Stage 1High Fluctuating

Total Population

Birth Rate

Death Rate

Stage 1 • Low population– Increasing very

slowly

• High birth rate

• High death rate

• Ethiopia/Niger

• UK: pre-1780

Reasons for Stage 1High Fluctuating

Total Population

Birth Rate

Death Rate

Stage 1 • Little access to birth control• Many children die in infancy

so parents have more to compensate

• Children are needed to work on the land

• Some religions encourage large families

• Death rates are high due to disease, famine, poor diet, poor hygiene, little medical science

Stage 2Early Expanding

Total Population

Birth Rate

Death Rate

Stage 2 • Population growing at faster rate

• High but decreasing birth rate

• Decreasing death rate

• Sri Lanka/Bolivia

• UK: 1780-1880

Reasons for Stage 2Early Expanding

Total Population

Birth Rate

Death Rate

Stage 2 • Improvements in medical care

• Improvements in sanitation and water supply

• Quality and quantity of food produced improves

• Transport and communications improve movements of food and medical supplies

• Decrease in infant mortality

Stage 3Late Expanding

Total Population

Birth RateDeath Rate

Stage 3 • Population, still increasing, but rate of increase slowing down

• Decreasing birth rate

• Low death rate

• Uruguay/China

• UK: 1880-1940

Reasons for Stage 3Late Expanding

Total Population

Birth RateDeath Rate

Stage 3 • Increased access to contraception

• Lower infant mortality rates so less need for bigger families

• Industrialisation and mechanisation means fewer labourers required

• As wealth increases, desire for material possessions takes over the desire for large families

• Equality of women means they can follow a career rather than just staying at home

Stage 4Low Fluctuating

Total Population

Birth RateDeath Rate

Stage 4• High population,

almost stable

• Low birth rate

• Low death rate

• Canada/USA

• UK: post-1940

Reasons for Stage 4Low Fluctuating

Total Population

Birth RateDeath Rate

Stage 4• Rates fluctuate with ‘baby

booms’ and epidemics of illnesses and diseases

• Reasons for Stage 4 have improved and it stabilises

Demographic Transition Model

Stage 1 Stage 2 Stage 3 Stage 4

Total Population

Birth RateDeath Rate

Ethiopia/NigerUK: pre-1780

NaturalIncreaseIn Population

NaturalDecreaseIn Population

Sri Lanka/BoliviaUK: 1780-1880

Uruguay/ChinaUK: 1880-1940

Canada/USAUK: Post-1940

Is there a Stage 5?

?

??

Stage 5: Depleting Population

Problems

• What problems do you think there could be with the model?

• It does not include the influences of migration• It assumes that all countries will go through

the same pattern• There is no time scale• Reasons for birth rates and death rates are

very different in different countries• And finally, is there a stage 5?

The End?

Population Pyramids

• The population structure of a country is how it is made up of males and females of different ages.

• The common method to show the structure is by a population pyramid.

• This diagram is made up by putting two bar graphs (one for male, one for female) side by side.

• From this you can read off what percentage of a population is of a certain gender and age range.

Developing Countries• This population pyramid is

wide at the base, which means there is a large proportion of young people in the country.

• It tapers very quickly as you go up into the older age groups, and is narrow at the top.

• This shows that a very small proportion of people are elderly.

Developed Countries

• This shape is typical of a developed country. • It is narrow at the base, wider in the middle, and stays quite

wide until the very top, as there is a sizable percentage of older people.

• Note that there are more old women than men.

Ever-Changing Populations

UK Population – 1995-2050

Different Population Pyramids

Stage 2 Stage 3

Stage 4 Stage 5

Population Sketches

Stage 2 Stage 3

Stage 4 Stage 5

Urban v. Rural Structures

Differences between Models

Demographic Transition Model

Population Pyramid Model

•Drawn as a line graph •Doesn't show male and female populations •Shows total population as a separate line •Gives details of countries in stages •Shows the relationship between birth and death rates and how these affect total population •Only one diagram necessary to show all stages

•Drawn as a bar graph •Shows male and female population proportions •Total population is shown as the total area of the graph •Shows greater detail about the populations at each stage •4/5 diagrams necessary to show all stages

Population Pyramid for …?…