The human population started to rise perceptibly at around 1800 BC. The numbers begin to rise dramatically about 200 years ago. What causes these changes? Revolutions! There have been several: agricultural, health, industrial, green, Farming developed about 10,000 years ago. Farming meant a steady supply of food and people could settle in villages instead of wandering after their food. The rise at around 1800 BC is due to increased farming and the rise of cities and towns. Then around 1800 AD, the population begins jump. Why? Health care has been improving over the last two centuries. Vaccines were developed that could prevent many diseases and antibiotics were discovered that could cure most infections caused by bacteria.
In the 1700's, the Industrial Revolution changed the source of power from humans to fossil fuels. This allowed more work to be
done.

The Green Revolution followed in the mid-1900's and continues today. The Green Revolution has allowed billions of people to be added to the population in the past few decades through advances in agriculture. How are the Industrial and Green Revolutions
connected?

A)
Increasing access to water: building more dams to provide a water source
for crop irrigation.

B)
Increased use of genetic engineering: Improving crops by selecting for
certain genetic traits.

C)
Increased use of agricultural machinery: plowing, fertilizing, picking, and
transporting using machines are powered by fossil fuels.

D) Increased use of inorganic fertilizers and chemical pesticides to maximize
crop production on a given amount of agricultural land.