ECO Note Home Page
I. Population Growth Predictions
The time it takes a population growing at a given rate to double in size
II. Consequences of exploding population
|loss of ag land|
|loss of biodiversity|
|increase in disease|
|loss of wetlands|
|increase in waste production|
III. Opposing arguments that predict the future of the human population
People use resources and produce pollution.
Eventually, resources will become scarce and pollution will become debilitating.
The population will then decline as a result of resource scarcity and pollution.
People are creative.
Any problems that develop, as the population increases will spark creative inventions that enable further population growth.
There will be no population decline.
IV. Reasons for human population explosion
Causes of disease recognized Improvements in nutrition Discovery of antibiotics Improvements in medicine Increase in number of women who actually reach child-bearing age Short doubling times in some countries
World population is 6.7 billion +
By 2025 it will be 7.8 billion
Between 1963 & 2004 the world’s population grew from 3.2 billion to 6.7 billion people
The growth rate dropped from 2.2% to 1.33% which still adds 77-80 million people a year
93% of the world’s population live in areas with fertility reduction programs.
Most governments spend only 1% of their national budget on fertility programs
(Since being elected President Bush has cut funding to international programs that control fertility)
There are 6.7 billion people on Earth
If each one stood up, pronounced their name, and sat down
It would take 600 years to complete roll call
By 2025 it will take 1,000 years to complete this exercise
U.S. population has grown from
90 million in 1900
273 million in 1999
300 million 6:47am on Tues Oct 18, 2006
394 million in 2050?
|60% of the population in the U.S. is because births outnumber deaths by 1.64 million/year|
(40% of the growth is from immigration 1.1million/year)
V. Developed vs Developing Nations
Moderately Developed Nations
82% of the world’s population lives in developing countries
98% of the world’s population growth; 75 million people a year occurs in developing countries
VI. Population Change =
Births + Immigration) - (Deaths + Emigration)
zero population occurs when:
(Births + Immigration) = (Deaths + Emigration)
VII. Population Decline
|88 countries representing only 13% of the world’s populations have stable or declining populations.|
|Japan has a low birthrate and almost 0 immigration. The population is expected to decline from 127 million in 2000 to 67 million in 2100.|
What special problems can arise?
2. Severe medical and social problems because there are not enough people to take care of the older generation
3. Fewer people have to pay more to keep social security type programs solvent.
VIII. Factors that Influence Population Growth
A). Biological Factors
How many women are having children and the number of children each woman will have.
Total Fertility Rate
Average number of babies a woman will have.
Crude Birth Rate
Number of births per 1000 individuals per year
2.1 children/woman is the replacement rate
The average number of children a woman will have has dropped from 5 in 1950 to 2.53 in 2005
1.5 in developed countries
3.5 in developing countries
5.2 in Africa
Lowest is Hong Kong at .91 and the highest is Somalia at 6.84
U.S. = 2.08 children/woman
2). Crude Death Rate
number of deaths per 1000 individuals
High death rates usually indicate infant/children mortality.
If the death rate falls—people live longer & the population will increase even if the birth rate falls
But eventually the population decreases because people that live longer have fewer children
life expectancy (how long an infant is expected to live)
|75 years in developed countries|
|66 years in developing countries|
|39 years in Botswana|
Infant mortality: how many babies out of 1000 die before their first birthday
|6.5 in the U.S.|
|8 in all developed countries|
|62 in developing countries|
What factors affect the death rate?
public health systems
3) Age Distribution
Age structure or population profile is the number of people of each age group (a group is 5 years) divided by sex (males on the right and females on the left)
Tracking the Baby Boomers
In 2000 baby boomers made up 50% of all adults
By 2030 2-% of the U.S. population will be over 65 years old
Profiles help to determine how many individuals are capable of giving birth
Used for economic and political decisions:
Pension and Medicare programs
Who to market to
Predict labor shortages
Need for schools
|Developed Nations||Developing Nations|
The effect of the current age structure of future population growth.
Young populations will continue growing due to reproduction of already existing age groups
B). Social Factors That Influence Birth Rate
1). Cultural and religious practices
2). Status and desires of women in the culture
|opportunities for women particularly education.|
|age of marriage and first child|
Women work 2/3 of all work hours for only 1/10 of the world’s income and .01% of the property.
3) Availability of birth control and legal abortion
|contraception use is only 26% in Africa|
|Birth control for married women has gone from 10% in 1960 to 49% in 1999 (world wide) and 59% in developed countries.|
|Expanding family planning world wide would cost $17 billion a year and would result in a decrease:|
|of 5.8 million births &|
|5 million abortions per year|
4). Infant mortality
5). Children in the labor force
6). Cost of raising children
7). Availability of pension systems
8). Availability of health care
9). Overall death rate
C). Political Factors
Government policies on population growth and immigration.
This may include tax breaks and services for children.
Limits on the number of children a couple can have.
(voluntary or mandatory)
Does the government have any right to interfere with the birth rate?
How much affect can the government have?
The fertility rate in China is 1.8 children/woman
The fertility rate in India is 3.2 children/woman
2. Concentrate on development & economics
IX). Population Growth and Standard of Living
Standard of living refers to the quality of life
As the birthrate increases Ý
The standard of living decreases ß
Which comes first?
Does a high birth rate decrease the standard of living or does a low standard of living increase the birth rate