3.8 Human Population Dynamics

What did Malthus theorize?

Earth has a carrying capacity of humans, based on food production

Human population growth is faster than food production

Humans will reach carrying capacity limited by food

What did Malthus fail to recognize?

Humans have technological advancements that can alter carrying capacity

ex. synthetic fixation of nitrogen in 1918 leads to synthetic fertilizer, drastically increasing food supply

Growth rate

% increase in population (usually per year)

Crude birth rate (CBR)

births per 1000 people in pop.

Crude death rate (CDR)

deaths per 1000 people in pop.

Growth rate formula

|CBR - CDR| / 10

Doubling time (rule of 70)

the time it takes (in years) for a population to double

it is equal to 70 divided by the growth rate

Rule of 70 formula

70 / % of growth rate

Factors that increase population growth

Higher TFR = higher birth rate

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

High immigration level

Increased access to clean water and health-care (decreased death rate)

Factirs that decrease population growth rate

High death rate

High infant mortality rate

Increased development (education, affluence)

Increased education for women

Postponement of marriage age

Standard of living is..

what quality of life is like

Gross Domestic Product (GDP) is a key economic indicator of standard of living 

Life expectancy is…

a key health indicator of standard living

it’s the avg age a person will live to in a given country

it increases with access to clean water, health care, and food services

High GPD and life expectancy are…

high indicators of development and low population growth