3.8 Human Population Dynamics

Explain how human populations experience growth and decline.

• Birth rates, infant mortality rates, and overall death rates, access to family planning, access to good nutrition, access to education, and postponement of marriage all affect whether a human population is growing or declining.
• Factors limiting global human population include the Earth’s carrying capacity and the basic factors that limit human population growth as set forth by Malthusian theory.
• Population growth can be affected by both density-independent factors, such as major storms, fires, heat waves, or droughts, and density-dependent factors, such as access to clean water and air, food availability, disease transmission, or territory size.
• The rule of 70 states that dividing the number 70 by the percentage population growth rate approximates the population’s doubling time.
• Enduring understanding EIN-1: Human populations change in reaction to a variety of factors, including social and cultural factors.