Human Population

• Every 5 days, the population increases by…

That’s A Big Number!

1,000,000 people

• Demography is the study of human populations and population trends. • Changes in human populations are described in the same

terms as we just learned.

It All Applies

• Net migration rate - the difference between immigration and emigration in a given year per 1000 people in the country.

Same Ideas, Same Mathcrude births - crude deaths

10r % =

crude births= births/1000 crude death= deaths/1000

Doubling Time = 70r

Rate of Change in Population = Change in PopulationChange in Time

Percent Change in Population = Change in PopulationOriginal Population x 100

Population Growth Models

Exponential Growth!

• Limiting factors include: food, water, and shelter • When the population exceeds the food supply there is a deficit.

Are We There Yet?

• Technology intercedes, agriculture improves, which means there is now a food surplus.

Are We There Yet?• The question remains: Is there a point where

technology can’t provide enough food?

Are We There Yet?

• Human population is projected to stabilize between 6.8 and 10.5 billion by 2100.