APES

Chapter 7

US and world population

US: 342 million and World: 8.2 billion

How has the human population grown recently?

Human population has grown slowly throughout most of history but we have experienced exponential growth over the past 200 years (J-shaped curve).

What is it projected to do?

Projected to be 9.5 billion by 2050

Factors that have caused human population to grow so rapidly

• Ability of humans to spread into all areas of Earth

  • Regardless of habitat, climate

• Improved agricultural techniques

  • More food production

  • Better access to necessary nutrients

• Improved public health

  • Medicines, vaccines, antibiotics

  • Sanitation, water treatment

What are the Malthus’ ideas regarding population?

Belief that human population growth will outpace food production

Birth rate

number of births per 1000 individuals

Death rate

number of deaths per 1000 individuals

Total fertility rate

the average number of children a woman has in her life

• Declining world wide

Replacement level fertility rate

fertility rate required in order to offset deaths

• Fertility rate needed for population to remain stable

Life expectancy

average number of years people live in a given time/place

Infant mortality rate

number of deaths of children under age of 1 per 1000 live births

Child mortality rate

number of deaths of children under age of 5 per 1000 live births

• Both are higher in developing countries

• Both are generally decreasing worldwide

Doubling time

amount of time it takes for a population to double in size

How has HIV/AIDS affected Africa?

• Caused reversal of positive demographic trends (ex. life expectancy)

• Has removed large numbers of young adults from populations of countries -> continues state of poverty

  • Decrease in number of workers - less productivity, less support for young and old

What is an environmental refugee?

A person seeking refuge for reasons of environmental issues, for example lack of water, food, and rising seas.

Know top 5 countries in population and where they are

China, India, US, Indonesia, and Pakistan

Where are some densely populated regions on Earth?

North America, Middle east (towards India), west Asia

Age structure

distribution of ages of people of population

Age structure diagram

shows percentages/numbers of males and females in population

• 3 major categories of ages: pre reproductive, reproductive, and post reproductive

Challenges/concerns that arise from aging populations

• Causes labor shortages - must be replaced by automation or immigration

• Strain on health care and government services - shortages of healthcare workers, nursing facilities

• Financial challenges - social security, pensions

Baby boom

generation born between 1946-1964

Demographic transition:

the change in developing countries through the years

• Stage 1: population stays low - birth and death rates are high, high IMR, low life expectancy

• Stage 2: as countries develop death rates drop first, birth rates remain high = rapid population growth

• Stage 3 and 4: Birth rates then drop as development counties = population stabilizes

Where is most population growth occurring?

India, countries in Africa, US (in the early 20th century)

What are ways to stabilize population/lower fertility rate?

• (Factors affecting birth rates and death rates and why are fertility rates higher in developing countries)

  • Reduce population growth, lower fertility rates