Unit 1.2: How and why do populations change naturally?

DEMOGRAPHIC: Population structure - 'Greying' or aging populations, e.g. Italy and Germany.

ECONOMIC: Widespread proverty and poor living conditions.

SOCIAL/CULTURAL: Lack of exercise or sedentary lifestyle. Smoking, drinking or drug use. Take inoculations where avaliable. Education makes people aware of health risks. Education of healthy living. Increased medical research.

POLITICAL: Policies to improve access to education and healthcare. 

ENVIRONMENTAL: Too cold - hypothermia risk - e.g. Britain most winters. Too hot - Heat exhaustion e.g. France, August 2004. Natural hazards - tsunami/floods/tectonic hazards/extreme weather events. Danger of urban environments - crime/industrial/road accidents.

DEMOGRAPHIC 

High infant mortality rates

• Families often try to compensate for high infant child mortality by having a large number of children.
• This is in the hope that some of the children will survive and reach adulthood.
• In Africa (2000) a woman must have 10 children to have a 10% chance of survival.

High proportion of people living in the reproductive age range

• Girls often get married young, as they can start to reproduce from 12 years.
• A higher population means a higher rate of births leading to a population increase.
• Those surviving can reach the reproductive age range.

ECONOMIC

Children regarded as economic asset (producers)

• Viewed as producers rather than consumers.
• Parents will encourage them to contribute to the family income.
• Parents will encourage their children to have a large family as it could make for money for the family.
• The children can look after the elderly.
• They can be used for home/agricultural work for the family.
• E.g.Sub Saharan Africa, Asia and Latin America.

Children regarded as financial burden (consumers)

• It costs a lot of money to raise a child.
• E.g. approx $100,000 from birth to 18 years old.

SOCIAL/CULTURAL

Education

• More women are more career driven - this means that children are born later, so as a women's fertility rate ends around 45 years, they will have less children.
• Low literacy rates and drop of fertility rates.

Security in old age

• Many families have many children in the hope that they will look after them at an old age, as they don't get pensions. E.g. in Africa.

Religion (use of contraception/age and type of marriage)

• Some religions e.g. Jewish people, do not approve of using contraception.
• This can lead to high fertility and birth rates. 
• Catholics. 

Status in community

• To have a lot of children is regarded to have a high status in community. 
• E.g. Fai Mankoh has 6 wives and 36 children!

POLITICAL

Inducements and concessions offered to large families (pro-natal policies)

• Government can encourage families to have children. E.g. France. This will increase the birth rates of that country.

Anti-natal policies

• The one child policy. E.g. China.
• Enforcement of sterilization
• Encourage abortions.

War

• Post war 'baby boom'
• During war there was a low birth rate.

• Population pyramids are graphs that show the age structure of a population by age and gender.
• Normally males are of the left and females are on the right.
• Age categories are in 5 year increasing intervals labelled up the centre axis.
• The horizontal axis is measured in millions
• Expansive or expanding population pyramids have a triangular/pyramid shape. The wide base indicates a high birth rate and the narrow top indicates a narrow top indicates a high death rate.
• Stationary or stable population pyramids have a 1/2 ellipse shape. The base of this is similar in width to the population of reproductive ages which indicates a stable population.
• Contractive or contracting population pyramids have a narrower base than the reproductive age population. This indicates a decreasing population trend. The low birth rate is indicative of a well-developed country.

STAGE 1: High birth rate, rapid fall in each upward age group due to high death rates. Short life expectancy.

STAGE 2: Still as high birth rate. Fall in death rates as more living in middle age. Slightly longer life expectancy.

STAGE 3: Declining birth rate, declining death rate, more people living to an older age.

STAGE 4: Low birth rate, low death rate, higher dependency ratio, longer life expectancy.

The dependency ratio can be shown by calculations. It is the ratio between those in the non-economically active age group and those in the economically active age group.

Demographic structure:

• Life expectancy at birth is rising
• Life expectancy at 65 rising
• Fertility rising by 1.2%

Italy will face a much greater percentage of its population being inactive, reflected by over 45%+ increase in the total dependency ratio and an 85% rise in old age dependency rates between 2000 and 2030.

What do the italian government need to do?

• Rising retirement age
• Encouraging a higher birth rate
• Reducing less use of contraception

In 2003, Robert Maroni, offered 1000 Euros to every woman who had a second child. This was paid to 190,00 people and was extended to people who had a first child too. Rocco Falivena, gave 10,00 euros to increase the birth rate also.

Use:

• Offers good description of general trends.
• Provides basis for comparison between countries
• Predictive for fertility rates
• Attempts to offer explanation of transition changes
• Has provided a starting point for more sophisticated models.

Limitations:

• Derived from a limited database - European countries only eurocentric view that all countries would pass through the same four stages. In reality many countries especially in Africa will never become industrilised.
• Does not predict total population numbers for a country, as migration is not included.
• Causes in decline of birth rates not wholly understood
• Impact of external influences from other countries not concerned.
• Does not predict when transitions will occur, length of stay.

EUROPE:

• Suggest fertility decline is even - European countries do vary.
• Suggests fertility decline is linked to increase in literacy urbanisation and decreases in mortality.
• Ignores birth control in stage 1.

LEDC's

• The transition in fertility and mortality occurs in a shorter time.
• Growth of population is greater in LEDC's
• Comparisons with MEDC's because of the above^ are difficult.
• DR's have fallen faster and for different reasons than Europe.
• Mass contraceptive availability.