Transcript ch5,6review

Chapters 5-6
Population
Review
Important Facts
• 40% of population growth is US is due
to immigration (legal and illegal)
• China and India have 36% of world’s
population--US is 3rd with 4.5
• US infant mortality level is higher than
39 other countries. WHY?
Fertility
• Replacement Level Fertility vs. Total
Fertility Rate
– Why is RLF higher than 2? (2.1 developed
countries; 2.5 developing)
– TFR has declined since 1950 but is still
higher than RLF--what does this mean for
population growth?
• World Population Growth: 1.22%
• Developing Countries:
– Have 82% of population
– Growth Rate: 1.5%
• Developed Countries:
– Have 18% of population
– Growth Rate: 0.1%
Population Math
• Rule of 70 (doubling time): 70%/r%
• Population Change
(birth + immigration) - (death+emigration)
• Population Density: population/area
• Birth or Death rate: #birthordeath/population
• Population Growth Rate (r):
birth-death/total population
(convert to percent)
2 Factors that Indicate Overall
Health of Country
• Death Rate
– The rapid population growth of the world is
due more to decreasing death rate than to
births
• Infant Mortality
– Discuss factors that affect infant mortality
Most Important Statistic for
Predicting World Population
Growth
• 28% of world’s population was under
age 15 in 2008
Population Pyramids
• Compare developing vs. developed
countries
• Zero Population growth countries-shape
of pyramid? Problems with declining
birth rates?
Demographic Transition Model
• Name and explain each stage
• Demographic Trap? Why are countries
“stuck” in Stage 2?
China vs. India
• Why has China been more successful in
curbing population growth?
Species Interactions
• Competition
– Ways to reduce competition?
• Predation
– Ways to avoid predation
• Commensalism
• Mutualism
• Parasitism
Coevolution
Population Graphs
• Exponential: J-shape
• Logistic: S-shape
Sheep in Tasmania
Moose in Alaska
• Why can sheep maintain higher levels
after they overshoot the carrying
capacity than the moose?
Small Populations
• Why a problem?
• What causes loss of genetic diversity?
• Relate to endangered species
Population Growth Cycles
• Stable, Irruptive, Cyclic, Irregular
• Lynx/Hare cycle
• Moose/Wolves in Isle Royale
– Bottom up versus top down control
Succession
• Primary vs. Secondary
• Relate to Dismal Swamp
• Facilitation, Tolerance, Inhibition