1. Population

3. Population terms Demography Fertility
The study of human population
Fertility
Amount of childbearing in a population
Several measurements of this

4. Demographic terms (cont.)
Crude birth rate
Live births per 1,000 people each year
High income nations e.g. U.S. = lower than average crude birth rate
The lower the average income, the higher the population increase

5. Demographic terms (Cont.)
Fecundity rate
Maximum possible childbearing
Sex Ratio
Males for every 100 females
Zero Population growth (ZPG)
Two people produce two people
Maintains population at a steady state

6. World population
Currently
6.7 Billion
Most of human history the population of the entire earth was 500 Million (1/2 billion)

7. Through most of human history, families had many children because:
Children were needed for the farm
Birth control was not reliable
High death rates = many children did not reach adulthood

8. Food increasing arithmetically Pop. Increasing geometrically
Malthusian theory
Food increasing arithmetically
Pop. Increasing geometrically
Result : People reproducing beyond what the planet can support
Out-stripping resources
Poisoning the planet

9. Demographic Transition Theory
Population patterns reflect a society’s level of technological development
From high births & deaths to low births & deaths.