Post on 07-Jan-2016
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Please get out your objectives #1-4 for a stamp.
While you wait for the stamp, compare your answers with your neighbors’. Add new or missing ideas in the lines between answers with a different colored pen.
No, don’t worry – I got this!
The ultimate in carpooling? LOL
Human population milestones
Which parts of the S-curve of population growth are already apparent?
Hunter Gatherer societiesNomadic – moved
aroundSmall family groups
Life expectancy low – poor nutrition, no disease prevention, hard life
Population was small because of limiting factors
What was the Agricultural Revolution, and how long ago did it happen?
Agricultural revolution – 8,000 BCE People learned how to grow food – a new technology that changed limitations of food
Change #1. Food surplus created demand for larger families (more kids meant more food produced)
Children increase agricultural productivity
Change #2. Settlements created along waterways for transportation – now people could trade for goods and food, even if they had a bad farming year.
What was the only time that population decreased significantly?
Bubonic Plague – 1390’s In Europe, killed 1/3 of population
When did humans begin their exponential growth?
Better nutrition (more variety, better preservation, greater quantity increased life expectancy)
Better sanitation (running water, sewage systems, garbage collection reduced death and disease)
Better health care (germ theory of disease, antibiotics reduced death and disease)
Changes after 1930
How big will our population get?
UN projection: 9.3 billion by 2050
World growth rate is has been decreasing since 1967
China’s peak projected for 2026 at 1.4 billion and then by 2045 it will be smaller than today
What are the three parts of the S-curve of population growth?
Does a population know when it reaches carrying capacity?
What happens to a population that goes above its carrying capacity?
Name four limiting factors that would set the carrying capacity for humans.
Why would the three changes after 1930 increase population size?
Check for understanding.