2.4 Population Dynamics Notes

}}The population of an area increases or decreases based on 3 major factors:}}

  1. }}How many babies are born → Fertility}}
  2. }}How many people die → Mortality}}
  3. }}How many people move in or out of an area → Migration}}

Fertility: (how many babies are born in an area)

  • The Crude Birth Rate (CBR) is the total number of live births in an area for every 1,000 people alive (live births/1,000 people)
  • The Total Fertility Rate (TFR) refers to the average number of children a woman will have in her childbearing years. TFR can vary widely, in Sub-Saharan Africa, the TFR is 5 and in Europe it is 1.5.

Morality: (deaths)

  • Infant Mortality Rate (IMR) refers to how many babes under one year of age die in each year compared to live births.
  • Crude Birth Rate (CDR) is the total number of deaths in one year per 1,000 people.
  • The Rate of Natural Increase (RNI) is the percentage by which population grows in a year.
  • “Natural” refers to the fact that only births and deaths are considered in this number, not migration
  • Least developed areas usually have the highest RNI
  • Population Doubling Time is the number of years needed to double a population
  • The Natural Increase Rate (RNI) affects doubling time, if the world’s RNA is 1.2% per year, the world population would double in about 58 years

Migration (permanent movement of people from one area to another)

  • Migration can contribute significantly to the amount of people living in an area either by many people moving in or by many people moving out.

}}Changes in population are due to mortality, fertility, and migration, which are influenced by the interplay of environmental economic, cultural and political factors.}}

Social Factors

  • Improvements in medical technology including immunizations drastically reduce the traditional causes of death like curable illness.
  • Improvements in education especially for women, lead to a reduction in the TFR (Total Fertility Rate).

Cultural Factors

  • When a society shifts its attitudes about the role of women in politics, workforce, and in family life, demographic changes often follow.
  • A society may also see a cultural shift in values, for example, from family-based values to more work based values causing people to have less children.

Political Factors

  • Pro-or-anti-natalist policies can encourage or discourage citizens from producing more children
  • Governments that want to control population can do so by providing incentive of punishments for people to have more or less children

Economic Factors

  • The Industrial Revolution produced wealth which allowed for improvements that made communities healthier places to live.
  • When societies shift the way in which they obtain their food and resources (less working by hand, using more machines) they have fewer children.
  • When there is a population shift to cities for work, children become a liability instead of an asset, thus leading to people having less children.

2.4 IMPORTANT VOCABULARY

Immigrant- People who moved into the country

Emigrant- People who moved out of the country

Crude Birth Rate (CBR)- The number of live births per year for each 1,000 people

Total Fertility Rate (TFR)- Focuses on women in their childbearing years of ages 15 to 49. The average number of children who would be born per woman of that group in a country

Life Expectancy- The average number of years people live

Infant Mortality Rate (IMR)- The number of children who die before their first birthday

Crude Death Rate (CDR)- The number of deaths per 1,000 people

Rate of Natural Increase (RNI)- The percentage at which a country’s population is growing or declining, without the impact of migration

Population Doubling Time- The time it takes to double in size