Topic 2.4

Essential Knowledge:  

 Demographic Factors Determining Growth & Decline 

Demographic factors that determine a population’s growth and decline are fertility, mortality, and migration.  

Fertility (births): 

• Crude Birth Rate (CBR): # of births per 1,000 people per year. 
• Total Fertility Rate (TFR): Average # of children per woman. 
• Replacement level = ~2.1 in developed countries. 

Mortality (deaths): 

• Crude Death Rate (CDR): # of deaths per 1,000 people per year. 
• Infant Mortality Rate (IMR): # of infant deaths per 1,000 live births. 
• Life Expectancy: Average # of years a person can expect to live. 

Migration (movement): 

• Immigration: People moving in (adds to population). 
• Emigration: People moving out (subtracts from population). 

Measuring Population Growth & Decline 

Geographers use the rate of natural increase and population-doubling time to explain population growth and decline. 

Rate of Natural Increase (RNI): 

• Formula = (CBR – CDR) ÷ 10 (expressed as %). 
• Does not include migration. 
• Positive RNI = population grows; negative = population shrinks. 

Population Doubling Time: 

• Number of years it takes for a population to double at its current growth rate. 
• Rule of 70: Doubling Time ≈ 70 ÷ RNI. 
• Example: If RNI = 2%, population doubles in ~35 years. 

3. Factors Influencing Fertility, Mortality, and Migration 

Social & Cultural: 

• Traditions, gender roles, religion → affect family size. 
• Example: Some societies value large families; others promote small households. 

Political: 

• Population policies (pro-natalist vs. anti-natalist). 
• War/conflict can reduce fertility and increase mortality. 
• Migration laws affect inflows/outflows. 

Economic: 

• Wealth increases access to healthcare, lowering mortality. 
• Urbanization → smaller families (less need for child labor). 
• Job opportunities attract migration. 

4. Regional & Global Examples 

Social, cultural, political and economic factors influence fertility, mortality, and migration rates. 

• High Fertility: Sub-Saharan Africa (youthful populations, expansive pyramids). 
• Low Fertility: Europe & Japan (aging populations, contracting pyramids). 
• High Mortality: Conflict zones, areas with poor healthcare access (e.g., Syria, parts of Sub-Saharan Africa). 
• Migration-driven growth: U.S., Canada, Gulf States (immigration). 
• Migration-driven decline: Eastern Europe (emigration of workers to Western Europe). 

Exam Tips:  

• Fertility, mortality, and migration are the three main levers of population change. 
• RNI and doubling time are tools to measure growth, but migration is a major outside factor. 
• Social, cultural, political, and economic forces shape these rates differently across regions. 

Contextualization

Video #1: Population, Sustainability and Maltheus 

This video provides a breakdown on how we analyze population dynamics, including Malthusian theory, which we will discuss more in 2.6

Video #2: Sex Ratio By Country 

This video provides the sex ratio for every country as of 2018 

Video #3: 7 Billion: How did we get so big, so fast?  

This video breaks down the factors that allowed for rapid population growth across the world.  

In Practice:

Essential Question 

Explain factors that account for contemporary and historical trends in population growth and decline.  

Conceptual Analysis Questions  

(FRQ Practice) 

1. Define the term sex ratio  
2. Explain how emigration impacts a country’s sex ratio  
3. Use two specific examples to describe how culture has contributed to sex ratio imbalance  
4. Use two specific examples to explain the societal consequences of sex ratio imbalance  
5. Define China’s one-child policy  
6. Compare the short-term and long-term effects of China’s one-child policy 
7. Explain the importance of evaluating and analyzing the sex ratio  

Vocab Review  

Provide a shorthand working definition for each of the following terms. This means it needs to be in YOUR OWN WORDS. 

• Epidemiological Transition Model 
• Total fertility rate                                         
• Stationary Population Pyramid 
• Infant Mortality Rate                      

MCQ:  

(You only need to write the letter for the answer you select). 

1. Which factor most directly explains why fertility rates tend to decline as countries develop economically? A. Increased need for agricultural workers 
   B. Stronger cultural preference for large families 
   C. Higher levels of female education and workforce participation 
   D. Reduced availability of healthcare services 
   E. Increased infant mortality rates 

2. If a country has a crude birth rate of 25 and a crude death rate of 10, what is its rate of natural increase (RNI)? A. 1.0% 
   B. 1.5% 
   C. 2.5% 
   D. 3.5% 
   E. 15.0%  
3. In recent decades, the United Arab Emirates has experienced rapid population growth primarily due to: A. High fertility rates among native citizens 
   B. High mortality rates balanced by rapid immigration 
   C. Immigration of labor migrants from South and Southeast Asia 
   D. Large-scale emigration of citizens to other regions 
   E. High dependency ratios caused by aging populations