7.9 Factors That Influence Human Population Growth

• Humans, unlike other kinds of organisms, can make conscious decisions based on the likely course of events and adjust our lives accordingly

7.9 Factors That Influence Human Population Growth

• Biological Factors– Demography is the study of populations and their

characteristics, how those characteristics affect growth, and the consequences of that growth.

– The total fertility rate (TFR) of a population is the number of children a woman has during her lifetime.

7.9 Factors That Influence Human Population Growth

• Biological Factors– A total fertility rate of 2.1 is known as replacement

fertility; parents produce 2 children who will replace the parents when they die.

– Zero population growth is when the birth rate equals death rate.

– The age distribution is the number of people of each age in the population.• (population pyramids)

7.9 Factors That Influence Human Population Growth

• Social Factors – Reducing fertility rates would be advantageous,

especially in LDCs (not everyone agrees)

– The major social factors determining family size are the status and desires of women in the culture.

– In male-dominated cultures, traditional role of women is to marry and raise children.

7.9 Factors That Influence Human Population Growth

• Social Factors– Early marriages foster high fertility rates.• In Africa, 17% of births are to women in the 15-19 year-

old range.• Total Fertility Rate of 5.0%

– Childrearing practices also influence population growth rates.• In countries where breast feeding is practiced, several

benefits accrue. – Breast milk is an excellent source of nutrients and antibodies.– During the months a woman is breast feeding, she is less likely

to become pregnant again.

7.9 Factors That InfluenceHuman Population Growth

7.9 Factors That Influence Human Population Growth

• Social Factors– Lack of education opportunities for women

reduces their options.– When level of education increases, fertility rates

fall.• Financial independence leads to marriage later in life.• Better-educated women are more likely to have access

to and use birth control.

7.9 Factors That Influence Human Population Growth

• Social Factors:– In some cultures women desire large families:• In countries where infant mortality is high, it is traditional to

have large families since several of a woman’s children may not live to adulthood.• Parents are more secure when there are many children to

look after their own needs in old age.

7.9 Factors That Influence Human Population Growth

• Economic Factors:– In less developed countries, the economic benefits

of children are extremely important.• Even young children can be given jobs that contribute

to the family economy– Protecting livestock, gathering firewood, or carrying water.

– In the developed world, large numbers of children are an economic drain.• They are prevented from working.• They must be sent to school at great expense.• They consume large amounts of the family income.

7.9 Factors That Influence Human Population Growth

• Political Factors – Governments can either reward or punish high

fertility rates.– Several European countries are concerned about

low birth rates and have instituted policies to encourage couples to have more children.• Paid maternity leave and guaranteed job availability

upon the mother’s return to work.• Childcare facilities make it possible for both parents to

work.• Child tax deductions provide an indirect payment to

families.

7.9 Factors That Influence Human Population Growth

• Political Factors– Most developing countries are concerned that

population growth is too rapid and have instituted programs to limit growth:• They provide information on family planning and

maternal and child health.• Sometimes governments provide free or low-cost

contraceptives.• One-child policy in China (Altered as of November

2013)

7.9 Factors That Influence Human Population Growth

• Immigration Policies– Birthrates are so low in some countries that

immigration is encouraged to offset a potential decline in the number of working-age citizens.

– Developed countries are under intense pressure to accept immigrants.• The higher standard of living is a magnet for refugees or

people who seek a better life than is possible where they currently live.