Human Population
Modern humans evolved in Africa about 200,000 years ago.
About 100,000 years ago, we began migrating across the globe.
Our population remained low—probably less than 1 million people.
With the advent of farming, growth picked up.
By AD 1, world population reached approximately 170 million people.
Year: AD 1 Human Population: 170 m
Dot = 1 million people
Han Dynasty
Roman Empire
Human population: 177 m
Silk Road
Year: 300 AD
Human population: 180 m
Golden Age of India
Year: 500 AD
Human population: 177 m
Peak Mayan Civilization
Year: 600 AD
Human population: 181 m
Birth of Islam
Year: 750 AD Human Population: 195 m
Smallpox in Japan
Year: 850 AD Human population: 215m
Gunpowder invented
Year: 1050 AD Human population: 283 m
Navigational compass
Year: 1200 AD Human population: 362 m
Mongol Empire
Year: 1350 Human population: 364 m
Bubonic plague Rare decline in world population
Year: 1490 AD Human population: 405 m
Europeans arrive
Year: 1520 AD Human population: 456 m
Transatlantic slave trade
Year: 1740 Human population: 714 m
Industrial Revolution Modern technology and medicine bring faster growth
Year: 1910 Human population: 1.7 b
World Wars
Year: 2015 Human population: 7.4 b
Year: 2050 Human population (projected): 9.5 b
LEVELING OFF
If current trends continue, global populations will peak at 11 billion around 2100.
Growth is slowing because average fertility rates are falling in nearly every country.
1950: 5 babies/woman
2100: 2 babies/woman
If fertility forecasts are slightly off, our peak population will peak lower...
...or higher.
It took 200,000 years for our population to reach 1 billion.
And only 200 years to reach 7 billion.
As our population has grown, so has our use of Earth's resources.
Choices we make today
family planning
reduced consumption
pollution controls
habitat protection
Choices we make today affect the future of our species—and all life on Earth.