Chapter 3 Flashcards
(29 cards)
What strategy do humans use?
Humans use K strategy
Characteristics of K strategy
Long lifespan, late sexual maturity, few young, high parental care
4000 BCE to 1347
Stable population, limiting factors are significant, S shaped growth curve
1347 to 1350
Bubonic plague (black death)
1700
industrial revolution, advanced agriculture methods, domestication of animals, advanced medicines, led to exponential growth
Today
J shaped exponential growth curve
Exponential population growth is a large concern on our planet
Two ways to examine population growth
- Percent population growth
- Doubling time
Percent population growth
Rapid population growth
Why? Birth rate remains the same but death rate has fallen
Doubling Time
The time it takes for a population to double in number. This has greatly decreased from 200 yrs, 80 yrs to 46 yrs
Death rate is ___ in developed countries
Slower
Death rate is ____ in developing countries
Faster
Demographic Transition
A. theory that describes the pattern if birth rates, death rates & growth rates of populations overtime
Stage 1: (pre transitions) early human societies
- high BR (no knowledge of birth control)
- high DR (no modern medicine)
- zero population growth
Stage 2: (early transition/demographic trap)
- high BR (no knowledge of birth control)
- low DR (more medicine, better food production)
- rapid population growth
- many under developing countries
- being trapped in stage 2 is called the demographic trap
Stage 3: (late transition/demographic transition)
- decreased BR (knowledge of birth control, better living standards)
- death rate decreases
- population growth slows
- most developing countries
Stage 4: (post transition)
- low BR
- low DR
- population growth slows to zero
- most developed counties
Stage 5: (constricting population growth)
- BR falls below DR
- population growth is shrinking
Population Pyramids
a bar graph used by demographers which shows the age distribution in a population
- can be used to predict the populations growth potential
- % of males in a different age group (left)
- % of females in different age group (right)
- age on y axis
Age Distribution=
% of people in different age groups
Expansive Population
- triangular shape
- rapid population growth, why?
- many young people of reproductive age
- fewer old people (not reproducing)
- decreased average lifespan (standard of living low)
- fertility rate: 4.7 children per female
Stable Population
- rectangular shape
- zero population growth, why?
- fewer young people of reproductive age
- increased average lifespan (high standard of living)
- fertility rate: 1.7 children per family
Constrictive Population
- inverted triangular shape
- negative population growth, why?
- fewer young people of reproductive age
- large number of people past reproductive age
Ecological Footprint
The amount of land that is required to support each person for their needs (food, water, transportation, housing & waste management in a country)
6 major categories to human demands…
a) crop land (how much land we require to grow food)
b) grazing land ( how many animals do we eat)
c) fishing ground
d) forest land (building & paper)
e) carbon absorption (transportation - cars, trains)
f) building area
