Population Why is population increasing at different rates

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Population Why is population increasing at different rates in different countries?

Population Why is population increasing at different rates in different countries?

Key Issue 3: Variations in Population Growth � The Main Points of this issue

Key Issue 3: Variations in Population Growth � The Main Points of this issue › The Demographic Transition � 1. Low growth � 2. High growth are: – 3. Moderate growth – 4. Low growth › Population pyramids �Age distribution �Sex ratio › Countries in different stages of demographic transition › Demographic transition and world population growth

Demographic Transition � All countries have experienced some changes in natural increase, fertility, and

Demographic Transition � All countries have experienced some changes in natural increase, fertility, and mortality rates but at different times and at different rates. � Demographic transition is the similar process of change in a society’s population � Demographic transition has several stages

The Demographic Transition Fig. 2 -13: The demographic transition consists of four stages, which

The Demographic Transition Fig. 2 -13: The demographic transition consists of four stages, which move from high birth and death rates, to declines first in birth rates then in death rates, and finally to a stage of low birth and death rates. Population growth is most rapid in the second stage.

Stage 1: Low Growth � � High CBR and CDR but nearly the same

Stage 1: Low Growth � � High CBR and CDR but nearly the same People depended mostly on hunting and gathering › Population depended on abundance of food � Around 8000 BC the world’s population began growing more rapidly › Agricultural Revolution: Humans begin domesticating plants and animals and no longer relied entirely on hunting and gathering. › More sustainable source of food, people began to live longer � Most of human history has been spent at stage 1, but no country remains there today.

Stage 2: High Growth � CDR plummets while CBR remains high › NIR is

Stage 2: High Growth � CDR plummets while CBR remains high › NIR is high Several countries entered stage 2 around 1750 when the world population began to rapidly grow � Countries entered stage 2 as the result of the Industrial Revolution � › Began in England in the late 18 th century › Major improvements in industrial technology that transformed the process of manufacturing goods and delivering them to market › New machines helped farmers increase agricultural production › Wealth from the Industrial Revolution was used to improve sanitation and personal hygiene

Stage 2: High Growth (cont. ) � Europe and US entered stage 2 around

Stage 2: High Growth (cont. ) � Europe and US entered stage 2 around 1800 but did not diffuse to Latin America, Africa and Asia until 1950 s � Latin America, Asia and Africa entered stage 2 following the Medical Revolution › Improved medical practices eliminated many of the traditional causes of death in LDCs and enabled people to live longer healthier lives.

Stage 3: Moderate Growth � DBR drops sharply, CDR is still dropping but not

Stage 3: Moderate Growth � DBR drops sharply, CDR is still dropping but not as rapidly › Population is still growing but as rapidly � � Europe and North America: 1900 -1950 Asia and Latin America: recently Most African nations are still in stage 2 CBR drops because of changes in social customs › People chose to have fewer children �More confident that children will survive to adulthood �Economic changes, more urban

Stage 4: Low Growth � CBR declines to a point that it equals the

Stage 4: Low Growth � CBR declines to a point that it equals the CDR › zero population growth (ZPG) � Countries in stage 4 can be seen in the TFR map � Social customs can also explain stage 4 › More women in the workforce › Changes in lifestyle: birth control, increased income and leisure time

Stage 4: Slow Growth � Russia and many Eastern European countries have negative NIRs

Stage 4: Slow Growth � Russia and many Eastern European countries have negative NIRs › CDR far exceeds CBR › High death rates from pollution and lower birth rates because of family planning programs and pessimism about having children in an uncertain world (communism)

The Demographic Transition in England Stage 1 Stage 2 Stage 3 Stage 4 Unit

The Demographic Transition in England Stage 1 Stage 2 Stage 3 Stage 4 Unit 1750 -1880 -early 1970 s Early 1970 s. Present

Demographic Transition in England Fig. 2 -14: England was one of the first countries

Demographic Transition in England Fig. 2 -14: England was one of the first countries to experience rapid population growth in the mid-eighteenth century, when it entered stage 2 of the demographic transition.

Population Pyramids Population in a country is influenced by the demographic transition in two

Population Pyramids Population in a country is influenced by the demographic transition in two principal ways: the percentage of the population in each age group, and the distribution of males and females. A country’s population can be displayed by age and gender groups on a bar graph called a population pyramid.

Age Distribution � Dependency Ratio: the number of people who are too young or

Age Distribution � Dependency Ratio: the number of people who are too young or too old to work compared to the number of people in their reproductive years › The greater the number the greater the financial burden on those working to support those who cannot

Percent of Population under 15 Fig. 2 -15: About one-third of world population is

Percent of Population under 15 Fig. 2 -15: About one-third of world population is under 15, but the percentage by country varies from over 40% in most of Africa and some Asian countries, to under 20% in much of Europe.

Young Pop. vs. Older Pop. Young dependents outnumber elderly ones by 10: 1 in

Young Pop. vs. Older Pop. Young dependents outnumber elderly ones by 10: 1 in stage 2 countries, but the numbers of young and elderly dependants are roughly equal in stage 4 countries. The large percentage of children in Sub-Saharan Africa and other stage 2 countries strains the ability of poorer countries to provide needed services.

Changes in the Pyramid As countries pass through the stages of the demographic transition,

Changes in the Pyramid As countries pass through the stages of the demographic transition, the percentage of elderly people increases. More than one-fourth of all government expenditures in the United States, Canada, Japan, and many European countries go to Social Security, health care, and other programs for the older population.

Population Disparities The number of males per hundred females in the population is the

Population Disparities The number of males per hundred females in the population is the sex ratio. � In Europe and North America the ratio of men to women is about 95: 100. � In the rest of the world the ratio is 102: 100. � In poorer countries the high mortality rate during child birth partly explains the lower percentage of women. � The difference also relates to the age structure. � Societies with a high rate of immigration typically have more males than females. �

Population Pyramids in U. S. Cities Fig. 2 -16: Population pyramids can vary greatly,

Population Pyramids in U. S. Cities Fig. 2 -16: Population pyramids can vary greatly, with different fertility rates (Laredo vs. Honolulu), or among military bases (Unalaska), college towns (Lawrence), and retirement communities (Naples).

Countries in Different Stages of Demographic Transition No country today remains in stage 1

Countries in Different Stages of Demographic Transition No country today remains in stage 1 of the demographic transition, but it is interesting to compare countries in each of the other three stages.

Rapid Growth in Cape Verde Fig. 2 -17: Cape Verde, which entered stage 2

Rapid Growth in Cape Verde Fig. 2 -17: Cape Verde, which entered stage 2 of the demographic transition in about 1950, is experiencing rapid population growth. Its population history reflects the impacts of famines and out-migration.

Moderate Growth in Chile Fig. 2 -18: Chile entered stage 2 of the demographic

Moderate Growth in Chile Fig. 2 -18: Chile entered stage 2 of the demographic transition in the 1930 s, and it entered stage 3 in the 1960 s.

Low Growth in Denmark Fig. 2 -19: Denmark has been in stage 4 of

Low Growth in Denmark Fig. 2 -19: Denmark has been in stage 4 of the demographic transition since the 1970 s, with little population growth since then. Its population pyramid shows increasing numbers of elderly and few children.