GLOBAL POPULATION GROWTH
1830 the world’s population reached ONE BILLION
1930, just 100 years later the population reached 2 billion.
1960 it reached 3 billion
15 more years later in 1975, it climbed to 4 billion.
12 years later in 1987, it crossed the 5 billion mark.
12 years later in 1999 the world’s reached 6 billion
By 2029, the world’s population is estimated to be 10.4 billion
DISTRIBUTION OF WORLD’S POPULATION:
1. East Asia: Approximately one-fourth of the world's population lives in the East Asia region comprising eastern parts of China, Japan, the Korean Peninsula and the island of Taiwan. Five-sixths of the people in this region live in China.
2. South Asia has the second largest concentration of people. The region comprises India, Pakistan, Bangladesh, and Sri Lanka. More than 20% 0f the world's population lives in South Asia and India, the world's second most populous country contains more than three-fourths of the people in this region.
3. South-East Asia: A third Asian population cluster, and the world's fourth largest comprise series of islands that lie between Pacific and Indian Oceans. The largest concentration is on the island of Java (Indonesia) inhabited by more than 100 million people. Indonesia consists of more than 13,677 islands and is the fourth most populous country in the world. Included in this region is Philippines.
4. Europe: The world's third largest population cluster encompasses about two dozen countries that occupy much of Europe from the United Kingdom to western Russia. Approximately 15% of the world's people live in this cluster.
5. North America: The largest concentration of people in the Western Hemisphere is in the Northeastern United States and South Eastern Canada. Approximately 150 million people live in this region and like the Europeans, most Americans are urban dwellers and fewer than 5% are farmers.
Sparsely Populated Areas: Harsh environments such as deserts and very cold tundra or hot and wet tropical regions are sparsely populated. The largest desert region of the world extends from North Africa to Southwest and Central Asia and includes Sahara, Arabian, Thar, Makan and Gobi deserts. The largest desert region in the Southern Hemisphere is found in Australia.
THEORIES ABOUT POPULATION GROWTH:
1. Malthusian Theory: Population growth and Food production: Thomas Malthus (1798)
2. Population as an Asset: Esther Boserup (1965, 1981) and others.
3. Poverty, (not Population growth) is the Problem: by Karl Marx,
THE DEMOGRAPHIC TRANSITION THEORY
Demographic transition refers to changes in population growth that occur when a country moves from high birth and death rates to low birth and death rates as the country embarks upon industrialization. The changes take place in 4 stages of a nations development:
Stage 1: Pre-Industrial Stage: the country is in the pre-industrial state, high birth and high but fluctuating death rates death rates are experienced.
Stage II: Early Industrial Stage: Death rates fall because of improving economic and social conditions but birth rates remain high.
Stage III: Industrial Stage: Birth rates begin to fall due to industrial development, education and jobs. Death rates also falls due to advanced medical practices, research and improved living conditions.
Stage IV: Post-Industrial Stage: Zero population growth, death rates falls drastically and birth rate is low but fluctuates.
Why Cant Developing Countries today take advantage of the Demographic Transition
1. Lack of trained personnel for industrial development.
2. Lack of an essential energy base and or a combination of factors
3. Rapid population growths and the resulting cycle of poverty prevent savings and investment.
4. Lack of financial resources.
HUMAN POPULATION GROWTH: (factors)
1. A broader worldwide food base developed from improvements in trade and global transportation.
2. Humanity developed resistance to several diseases.
3. Better medical technology and research led to an increase in survivorship and a drop in child and infant mortality.
4. Improvements in general living conditions mean longer life span for many people.
5. The change from pre-reproductive to post-reproductive death with development in medical science has helped people to give birth before they die.
Natural Increase: is a measure of population growth that examines the difference between births (fertility) and deaths (mortality) in a country for a given year.
The number of persons born per 1,000 individuals in population for a given year is the Crude Birth Rate
The number of persons per 1000 individuals in a population who die in a particular year is the Crude Death Rate.
Total Fertility Rate is a measure of the average number of children a woman can have during the reproductive years of her life (15 - 49 years). It is an average figure that reveals the number of children per family. In 1990, the total fertility rate for American women was 2.0, after declining from about 3.3 in 1950 to 1.8 in 1985. It is currently less than 2.
On the global scale, the total fertility rate was 3.0 in 1996. It was higher (3.4) in developing countries and lower (1.6) in developed nations. Africa in 1996 had a fertility rate of 5.7, S.E Asia has 3.6 and the Caribbean 3.1
How has fertility rates changed in the United States?
United States total population grew from 76 million in 1900, to 265 million in 1996 - a 3.5 fold increase even though the total fertility rate has oscillated widely. In 1957, the peak of the post World War II baby boom, the Total Fertility Rate reached 3.7 children per woman. Since then, the rate has declined to about 2.0 in 1990 and has remained below replacement level since 1972. The drop in fertility rate has not led to a significant decline in the growth of population in the US compared to European nations. This is due to a number of reasons:
1. Large number of wealthy baby-boom women who are still in their giving birth to children.
2. An increase in the number of teenage pregnancies.
3. High fertility rates for women (minorities) in racial groups other than Caucasian women.
4. High levels of legal and illegal immigration (accounts for 40% of current US population growth).
Reasons for Disparities in Total Fertility Rates Between Nations
1. The society’s view of children as family income earners or part of the population undergoing training and receiving education.
2. The absence of private of public Old Age Social Security payments encourages parents in poor countries to bring forth children who will take care of them in their old age.
3. Educational and Career Opportunities, particularly for women, can cause drop in population growth.
4. Status of Women in Society. When several women move from the home to obtain jobs, population growth declines in the country.
5. Some religions such as Muslim encourage men to have more wives and several children while others such as the Roman Catholic does not support abortion and rather teaches celibacy, abstention and one man one wife.
6. The availability of safe family planning and birth control services helps prevent unwanted pregnancies.
7. Infant Mortality: Frequent deaths to infants have been a motivation factor to families to experiment with more childbirth so a few could live.
8. Average level of affluence and education in the society
9. Cost of raising and educating children in the particular society.
10. Average age at Marriage, particularly for women can influence population growth in a given society.
AGE STRUCTURE OF A POPULATION
The age structure is the number of individuals occurring in each age class within a population. The diagram displaying the age structure of a population is often called a Population Pyramid. A pyramid depicts the pattern of growth in the population of a country. To construct the population pyramid for a country, follow the steps below:
1. Classify the population first (1) by sex into males and females and then (2) into age groups of 5-year intervals (0-4. 5-9, 10-14 etc.) called cohorts. In a census data, look for tables that show the characteristics described above.
2. Compute percentages of the actual number of people in each five-year category for both males and females (example, (a) total of females aged 0-4 / total population * 100 = ---%. (b) Total males aged 0-4 / total population * 100 = --- %). Do the same for all cohorts
3. Graph the percentages of 5-year age groups for males and females (on x-axis) against the age groups (0-4, 5-9, 10-14, etc on y-axis) .
4. On the graph, percentage for Males is shown on the Left of the middle axis and the percentage of Females shown on the Right.
5. The pre-reproductive age is usually between 0-14, Reproductive age 15-44 and post-reproductive age 45-85+
i) Rapidly growing populations have broad based population pyramids. This is characteristic of poor developing countries of Latin America, Africa and Asia.
ii) Stable populations have pyramids that are elongated with a narrow base. Populations of several European countries including France, Netherlands and the Scandinavian countries, and also USA and Canada depict have stable populations.
iii) Declining Populations have pyramids with a very small base and slightly large tops. Austria, Germany (East and West), Japan and other developed nations have declining populations. There tend to be a large proportion of senior citizens in the population.
Relevance of Age-Structure Diagram
1. It indicates the occupation structure of the population.
2. It provides information about both sexes in the population. A proportion of more women below the age of 15 years in the population provide an indication of a possible high future growth rate.
3. Provide clues to present and the future trends in the growth rates of the population.
4. It provides information about the impacts that past events such as wars and economic booms had on the general population. The impacts are registered as deaths and births.
THE DEPENDENCY RATIO:
In terms of economics, the population of a country can be divided into the following categories:
a) 0-18 years = Economically dependent group
b) 19 – 65 = The Labor Force; comprising the working people that pays income tax to run the country.
c) 65+ years = Senior citizens; also economically dependent group
The dependency ratio for a country’s population is calculated as:
Total Populations (0 - 18 + 65+ yrs.) 100
Total Population 19 – 65 year olds X 1
ADDRESSING THE POPULATION PROBLEM
Improving the Lives of the People to Decrease Population Growth.
a). Increasing food production
b). Food Aid.
a) Undercuts domestically produced food leading to losses to local farmers, and lower agricultural outputs.
b) Introduces the population to diets other than what is locally available thereby necessitating imports.
c). Social and Economic Development.
DIRECT METHODS TO CONTROL POPULATION GROWTH
Reducing Fertility to Bring down Population Growth
a) Family Planning Methods
b) Demographic Transition Theory
e) One Family One Child Policy