1. Studying Human Populations
The Human Population
Studying Human Populations

2. The Human Population Over Time
Demography- The study of populations
Most often human pop.
Study historical size and makeup
Human pop. Had slow growth until 1800s
Underwent exponential growth
Industrial and scientific revolutions

3. World Population Over Time

4. Forecasting Population Size
Age structure- The distribution of ages in a specific population at a certain time
Population pyramid- Double-sided bar graph to illustrate age structure

5. Forecasting Population Size
Survivorship- The percentage of members of a group that are likely to survive at any given age.
Survivorship curves- Graphs of survivorships

6. Forecasting Population Size
Fertility rates- The number of babies born each year per 1,000 women in a population
Declines with increased education and economic independence for women
1.6 children per woman in developed countries
3.1 children per woman in developing countries
Replacement level- Number of children a woman must have in order to “replace” themselves

7. Forecasting Population Size
Migration- The movement of individuals between areas.
Immigration- Movement into an area
Emigration- Movement out of an area

8. Declining Death Rates
Life expectancy- The average number of years a person is expected to live.
Most affected by infant mortality (death rate of infants under 1 year)

9. The Demographic Transition
Model that describes population growth changes.
Based on observations of history
Compares birth rates, death rates and population size
Stages of the transition:
Stage 1- Preindustrial
Stage 2- Transitional
Stage 3- Industrial
Stage 4- Postindustrial

10. The Demographic Transition