3.8 - Human Population Dynamics

Malthusian theory

- Earth has a human carrying capacity, probably based on food production

- Human population growth is happening faster than growth of food production

- Humans will reach a carrying capacity limited by food

Technological Advancement contrary to Malthusian Theory

Humans can alter earth's carrying capacity with tech. Innovation

- Ex: synthetic fixation of Nitrogen in 1918 leads to synthetic fertilizer, dramatically increasing food supply

Rate of Natural Increase (r)

% increase in a population (usually per year)

- Ex: a growth rate of 5% for a population of 100

means they grow to 105

equation for Rate of Natural Increase

(CBR - CDR) / 10

Crude Birth Rate

The number of live births per year per 1,000 people.

Crude Death Rate

The number of deaths per year per 1,000 people.

Doubling Time

Rule of 70: The time it takes (in years) for a population to double is equal to 70 divided by the growth rate or Rate of Natural Increase

- Ex: Global growth rate = 1.2% 70/1.2 = 58.3 years

• Global pop. will double in 58.3 years

Calculating Population Change

Practice Problem: A country has a CDR of 9 and a CBR of 18.

Calculate the annual growth rate, and the doubling time

SOLUTION: (18-9)/10 = 9/10 = 0.9% Growth Rate

70/0.9% = 77.77 years to double

Factors increasing Human population growth

1) Higher TFR → higher birth rate

2) High infant mortality rate can drive up TFR (replacement children)

3) High immigration level

4) ncreased access to clean water & healthcare (decrease death rate)

Factors that decrease population growth

1) High death rate

2) High infant mortality rate

3) Increased development (education & affluence)

4) Increased education for women

5) Delayed age of first child

6) Postponement of marriage age

Standard of Living

What the quality of life is like for people of a country based on GDP and Life expectancy

**Note: High GDP & life expectancy are both indicators of development & low pop. growth

GDP (Gross Domestic Product)

key economic indicator of standard of living

- Total value of the goods & services produced

- Per capita GDP is total GDP/total population

Life Expectancy

key health indicator of standard of living

- Average age a person will live to in a given country

- Increases with access to clean water, health care, stable food sources

Female Education and TFR

- More education = fewer unplanned pregnancies

- More education = more job opportunities for women

• Alternative to marrying young