3. How has human population grown? Slowly over time Scarce food and incurable disease Death rate high Families had many childern 500 years ago Raid growth Why? Agriculture, industrial; revolution, better food supply, shipping methods improved, improved sanitation, healthcare, improved medicine Led to expanded human growth
4. Science Behind Human Population Thomas Malthus English Economist Human population cannont grow exponentially Limits: Famine, disease, war
5. Demography Scientific study of human population Study a variety of social and economic factors that effect human population Examines characteristics of human population and attempts to explain how and why human population changes over time
6. Things that help predict different population growth rates Birth rate Death rate Age structure
7. Hypothesis These countries have completed a “demographic transition”, a dramatic change in birth and death rates Historically: humans have high birth and death rates Now: High birth rate and LOW death rate Because of better conditions of living
25. Controlling Human Population India Compulsory sterilization China Family planning program Benefits and bonuses Forced abortions
26. Predicting Future Population Growth Many factors Age structure of countries Prevalence of life threatening diseases By 2050 9 billion Growth will level off or decrease if countries growing rapidly go through demographic transition
27. Lower growth rate means population growth is slowing by it is STILL growing How does this effect environment? Ecologists predict that if this growth does not slow even more there will be Serious damage to Environment Global economy Other ecologists predict that science, technology, and changes in society will control those negative impacts on economy and environment
