IB Topic 3.1 Human Population

Dynamics

Subtopics

3.1.1 Describe the nature and explain the implications of exponential growth in human populations.

3.1.2 Calculate and explain, from given data, the values of crude birth rate, crude death rate, fertility, doubling time and natural increase rate.

3.1.3 Analyze age/sex pyramids and diagrams showing demographic transition models.

3.1.4 Discuss the use of models in predicting the growth of human populations.

3.1.1 Population Growth (Summary of how ecosystems change:TBCh4)

• Exponential growth: when organisms have enough food, water, and space… optimal conditions. But,

• Limiting factors:

• Density-dependent (usually biotic)o Internalo External

• Density-independent (usually abiotic)

• Carrying capacity (K): maximum number (or load) of individuals an environment can support SUSTAINABLY

Retrieved on 03-11-2011 from: http://www.sustainablescale.org/ConceptualFramework/UnderstandingScale/MeasuringScale/CarryingCapacity.aspx

Retrieved on 03-11-2011 from: http://www.unesco.org/ldc/images/World.gif

3.1.1 Vocabulary & Terms• Human Development Index (HDI):

• Is measure of “well-being” in a country

• Life expectancy

• Standards of living

• Education

• Per capita gross domestic product (GDP)

• MEDC: More Economically Developed Countries

• “Developed”: EU, North America, Japan, Israel, and others

• LEDC: Less Economically Developed Countries

• “Developing”: Most countries beyond above geographic boundaries

3.1.2 Growth Calculations• Crude Birth Rate (CBR):

number of births (natality) per 1000 individuals per year (where p = midyear popln, b and d = # of births and deaths per year.)

• Crude Death Rate (CDR): number of deaths (mortality) per 1000 individuals per year

• Natural Increase Rate (RNI): gives percentage growth (excluding migration)

• Doubling Time

• General Fertility Rate (GFR) number of births per 1000 women (15-49 yrs)

• Age-specific Birth Rate (ASBR) number of births per 1000 women (in a specific age group, in a geo. area)

• Total Fertility Rate (TFR) number of births per thousand women of childbearing age

TFR = (h x ASBR)/1000Where h=the number of years in the age cohorts for the ASFR.

• Replacement Fertility Level: enough babies to replace adults• MEDC ~ 2.03

• LEDC ~ 2.16

Calculating TFR from ASBR

• Age Specific Birth Rate

• = total number of births ÷ 1000 women of any specified year group (s)

3.1.1 Human PopulationsRetrieved on 20-01-2013 from: http://www.motherjones.com/files/images/total-world-population-chart-inline-400.jpg

3.1.1 Human K

• Carrying capacity• Technology

• Medicine

• Resource desire (dynamic)

• Resource needso urban vs. rural

o Wealth of population

Retrieved on 21-01-2013 from: http://steadystaterevolution.org/wp-content/uploads/2009/06/image002.jpg