Do populations continuously grow?
Not necessarily. The growth of a population depends on a number of issues. Obviously, the average age of the individuals of that population is important. But other factors, such as the local economy, also play a role.
Major changes in the human population first began during the 1700s in Europe and North America. First death rates fell due to technological improvements.
Death Rates Fall
Major advances in science lead to improvements in technology which led to lower death rates in 18th century Europe and North America:
- The Age of Enlightenment facilitated significant cultural changes away from corrupt dogmatic thought.
- The newly invented scientific method lead to discovery that micoorganisims cause disease, which led to improved water supplies, sewers, and personal hygiene.
- Science imporved farming techniques and engineers invented machines that increased the food supply.
- The Industrial Revolution of the 1800s led to new sources of energy, such as coal and electricity. This increased the efficiency of the new agricultural machines. It also led to train transport, which improved the distribution of food and allowed humans to spread over greater distances.
For all these reasons, death rates fell, especially among children. This allowed many more children to survive to adulthood, thus birth rates increased. As the gap between birth and death rates increased, the human population grew faster.
The effect of Government and Economics on birthrate
It wasn’t long before birth rates started to fall as well in Europe and North America. People started having fewer children because large families were no longer beneficial for several reasons.
- As child death rates fell and machines did more work, farming families no longer needed to have as many children to work in the fields.
- Laws were passed that required children to go to school. Therefore, they could no longer work and contribute to their own support. They became a drain on the family’s income and thus it did not make economic sense to have large families.
Eventually, birth rates fell to match death rates. As a result, population growth slowed to nearly zero.
Stages of the Demographic Transition
These changes in population that occurred in Europe and North America have been called the demographic transition. The transition can be summarized in the following four stages, which are illustrated in Figure below:
- Stage 1—High birth and death rates lead to slow population growth.
- Stage 2—The death rate falls but the birth rate remains high, leading to faster population growth.
- Stage 3—The birth rate starts to fall, so population growth starts to slow.
- Stage 4—The birth rate reaches the same low level as the death rate, so population growth slows to zero.
Stages of the Demographic Transition. In the demographic transition, the death rate falls first. After a lag, the birth rate also falls. How do these changes affect the rate of population growth over time?
- Social and cultrual changes lead to the Age of Enlightenment which lead to the scientific method
- The scientific method increased factual knowledge generation and accelerated engineering practice.
- Changes in the human population occurred in Europe and North America.
- Science and technology lead to death rates falling and allowed birth rates remained high. This led to rapid population growth.
- Later, economic thought lead birth rates to fell. As a result, population growth slowed.
Use this resource to answer the questions that follow.
- Demographic Transition Model at http://geographyfieldwork.com/DemographicTransition.htm.
- What does the Demographic Transition Model demonstrate?
- Describe stage 1 of the Demographic Transition Model. Why is birth rate high?
- Why does death rate begin to fall in stage 2 of the model?
- Compare stage 3 to stage 4 of the model.
- Stage 4 is characteristic of which countries?
1. How did the invention of agriculture affect human birth and death rates? How did it affect human population growth?
2. Outline the four stages of the demographic transition as it occurred in Europe and North America.