1. The Last 10,000 Years of Human History
By 1810, population ~1 billion
By 1922, population ~2 billion
By 1959, population ~3 billion
By 1974, population ~4 billion
By 1987, population ~5 billion
By 1999, population ~6 billion
By 2017, population ~7.6 billion
The present human population of the world is a little more than ______________. 
In the last 50 years of the 20th Century, world population grew from ______ billion to over 6 billion.

2. The Human Population Today
Growth rate = (birth rate) – (death rate)
Human population grows by about 70 million people per year
Present population of the world id 7.6 Billion
The growth rate is 1.1% per year
Doubling time = 200 years (In 2217 it will be 15.2)
The growth rate of the world population equals ________________.

3. Future World Population

4. What about? Too many people? Crowding in cities Crime Pollution
Illegal migration
Disease
Room for more people?
Our entire world population could fit inside 42 km x 42 km square in 2017 (Isle of Man + Isle of Wight)
Consider carrying capacity

5. Carrying Capacity How many people can Earth support?
Increasing amounts of food can be produced
People can migrate from areas of famine or poverty to less crowded or wealthier areas

6. Carrying Capacity Example of Rapa Nui (Easter Island)
Isolated Pacific island with poor soil and little water
Settled by people from Polynesia 400AD
Survived easily on chickens and yams, plenty of free time
Developed elaborate competition between clans with
Civilization peaked at 1650, with population of about 10,000

7. History Example of Rapa Nui (Easter Island)
Reached by a Dutch ship in 1722
Found 2,000 people living in caves
Primitive society and at war with each other.
Rapa Nui’s carrying capacity had been drastically lowered by society’s actions:
Transportation of moai had required cutting down trees
Erosion of soil made yams scarce
Lack of canoes made fishing difficult and escape impossible