The Study of Population

• Study of Population is called Demographics. • Two of the most basic factors that affect Population are Birth rates and Death rates – called Vital Statistics. • Birth and Death rates typically are stated as numbers per 1000 population per year. Eg. If a country has a birth rate of 8, this means that out of every 1000 people in that country 8 babies will be born in one year.

• Birth rates – Death rates = Natural Increase • When B.R. – D.R. = 0, we have a situation called Z.P.G. (Zero Population Growth) • Many of the highly industrialized nations are at or near ZPG. Germany, Japan, Italy and the Netherlands are some examples. A country can even have a natural decrease.

• At ZPG, the death rate has stabilized or even rising, but it is the birth rate that is dropping. Why?

• Role of Women – careers, education

• Children are too expensive • More leisure time – don’t have time for kids • Fear of the future – war, terrorism, economic bad times, etc.

• A Childless preferred lifestyle – D.I.N.K.S. (Double Income No Kids)

The key to population growth then is the Birth rate. Death rate is really dependent on Birth rate. Developing Countries that are facing population problems, experience these problems due to a high Birth rate.

Reasons for a High Birth rate: • High Birth rates occur to offset high death rates – eg. In the animal kingdom, one turtle has thousands of offspring, most will die, but the species will survive simply due to the large numbers of new turtles.

• In poor countries, governments do not offer old age pensions or security, so birth rates are high so that the children can take care of the elderly.

• More children to help on the farms – free, cheap labour • Military and strategic reasons – the larger the population the stronger the military • Religious, cultural, traditional reasons • Nothing to do – wait till you hear the explanation for this one!

• Role of women – women in some countries are considered second class and their sole purpose in life is to stay home and have children.

• Lack of an education and lack of knowledge of Birth Control This last one is interesting: People that support population controls (anti-natalist) are in favour of all types of Birth Control for the following reasons:

• Environment can’t support any more people • Pollution is on the increase • We are running out of resources • Our standard of living will decrease • Massive unemployment, disease, starvation, overcrowding will occur Some people are against Birth control (pro natalist) and these are the reasons they give:

• Wealth and population are directly proportional • Re-distribute the wealth • Re-locate population • Controlling population removes personal freedom (moral issue) and is against most religions, it is against nature • We will find ways of taking care of the extra people • Population will take care of itself – be optimistic

A model has been created to describe what happens as a country goes through various stages of birth rates and death rates. The model is called the

Demographic Transition Model

. There is a separate slide show on this later on.

A type of graph called a

Population Pyramid

was created to visually show the relationship of the age structure of a country and its male/female distribution. You will have an activity that will clearly illustrate population pyramids later on.

POPULATION PRYAMID FOR CANADA Source: http://www.statcan.ca/english/kits/animat/pyca.htm

• Population explosions occur when the birth rates are high and the death rates start to decline. This happened about 200 years ago.

• Death rates began to drop due to better health care, better food supply, a decrease in wars, better sanitation/hygiene • More people reached child bearing age.

• So while the death rate went down, the birth rate remained high, the gap (Natural Increase) between them increased.

• The wider and longer the gap continued the larger the population grew • In a developed country the birth rates eventually started to slow down, it even spread out due to oversea empires and urbanization.

• In a developing country the drop in birth rates took a long time. In some countries the birth rates still haven’t dropped.

• Children remained (remain) an economic asset, not a liability in the developing world.

• World natural increase for 1960 – 2.0% • In 1992 it was 1.7% • This still added 95 million people per year (based on a base of 6 billion) • That’s 256 000 people a day • 10 666 per hour • 180 per minute • 3 per second

• Declining natural increase rate does not mean a declining population • 1.7% of 6 billion (1990) is more than 2.0% of 3 billion (1960) • Natural increase is decreasing but the overall population is still increasing. This is called Population Momentum • For example – Which is greater?: a. You receive $1000 a day for 30 days OR b. You receive 1cent on the first day, 2 cents on the second, 4 on the 3 rd and 8 on the 4 th .

The ‘a’ example will get you $30 000. The ‘b’ example will get you $10 737 418.23!

Example ‘b’ grows in a compound fashion. Its growth depends on the previous days growth – that is how population grows.

• Birth rates and Death rates are affected by the age-composition of the population and this could lead to some confusion.

• For example: A population representing a developed country like Canada, may have a large proportion of old people and Canada’s death rate may actually be similar to that of a developing country that is made up of a younger population like India.

• Birth rates and Death rates are still the most important and easily understood of all the vital statistics, but it is worth looking at other types of vital statistics.

• So population can be measured in other ways that are free of this age-distribution influence.

• Two are: the

total fertility rate life expectancy at birth

.

(TFR) and the • The

total fertility rate

is the number of children a woman would have during her reproductive life if she experienced the prevailing rates of fertility at each age.

• In other words “the average amount of babies a woman will have based on that countries statistics.

• High-fertility countries may have birth rates of 40 or even 50 per 1000 population (per year); corresponding levels of the TFR would be 5 to 7 children per woman.

• Low-fertility countries have birth rates of 15 to 20 per 1000 and TFRs of about 2.

• “

Replacement level” fertility

(the level at which each person on average has a single successor in the next generation) corresponds to a TFR of about 2.1 under low death rate conditions.

•

Life expectancy at birth

is the average length of life if currently prevailing mortality rates continued indefinitely.

• Pre-industrial populations had large fluctuations in mortality – death rates.

• Pre-industrial populations had death rates of 30 to 40 per 1000; life expectancies of 25 to 35 years.

• With modern health care, death rates are below 10 per 1000 and life expectancies are above 70 years.

•

Infant mortality rate

is the probability of death in the first year of life, usually stated as a number per 1000 births.

• Many less-developed countries have infant mortality rates above 100 per 1000 - that is, more than 10 percent of the children die in their first year.

• In countries with effective health and educational systems, infant mortality rates are about 15 per 1000, or even lower.

Population Projections Encarta ‘97

Population Projections • 1990 5.3B to 6.2B by 2000 and 8.5B by 2025.

• 2025 “high” estimate 9.1B; “low” estimate 7.9B.

• Birth rates are expected to decline from 26/1000 in 1990 to 22/1000 in 2000 and 17/1000 by 2025.

• Because of the increasing number of elderly, death rates are not expected to fall much.

• 9/1000 in 1990 to 8/1000 in 2025.

• Life expectancy is expected to increase from 65 years (1990) to 79 years (2025).

• Important to note that these are world averages; the pattern is not uniform geographically.

The End!