Human Ecology Flashcards
How many humans are born every second in comparison to the number that die every second?
4 humans born and 2 die (Gain 2.3 humans every second)
Describe the variables in the equation G=ΔN/Δt and describe what the equation measures
G=Rate of change in the population size
ΔN= the change in the number of individuals
Δt= interval of time
Describe variables in G=rN
G= Rate of change in population size
N=Number of individuals in population
r=per capita rate of increase = birth rate – death rate
Specifically discuss r and what happens to population size when r> or r
r= per capita rate of increase
r>0 means that population is increasing
r=0 population size is constant
r
What is K and what happens to G when K is ,= N?
K=carrying capacity (number of individuals earth can sustain)
When K=N: Growth rate is zero
When K>N: Growth rate is positive
When K
What two types of factors influence population growth in nature?
1) Density Independent Factors
2) Density Dependent Factors
Describe birth rate:
Number of deaths per year per person
Total Fertility Rate
number of children born on average during a woman’s reproductive life
Doubling time:
Time it takes population to double in size
What percent of the worlds population and what percent of the world population growth do developing countries represent?
80%, 90%
What four factors determine total fertility rate?
Culture
Economic
Demographic
Political
What is the demographic transition model?
model of economic and cultural change to explain declining death rates, declining birth rates, and rising life expectancies in as become industrialized
What are the four transition stages in the demographic transition model?
1) Pre-Industrial Stage
2) Transitional Stage
3) Industrial Stage
4) Post Industrial Stage
What is happening to birth and death rates in Pre-Industrial stage?
Both rates are very high
What is happening to birth and death rates in transitional stage?
Birth rate is constant put death rate is decreasing due to food production and increased medical access
What is happening to birth and death rates in Industrial stage?
Death rates hit a constant level while birth rates begin to decline due to increased opportunity for woman and increased access to birth control
What is happening to birth and death rates in post Industrial stage?
Birth rates and death rates are low
What is the optimist economist view of human population growth?
world population growth will stabilize this century due to demographic transitions in developing countries.
Pessimist view of human population growth?
eloping countries of the world are too environmentally and/or politically unstable, and will not experience a demographic transition. Aid to developing countries will decrease death rates but not birth rates.
Technologist View
Improving in technology and investing in technology TODAY will outpace demands of increasing populatioins
Social Justice View
Population is a SYMPTOM not a problem. We must redistribute resources.
Ecologist View
Population growth is the problem. The earth has a carrying capacity. If developing countries proceed through the demographic transition the same way developed countries have, per capita resource consumption will put us over the carrying capacity.
What are two consequences of a growing population like that of the baby boom era?
Not enough people paying into social security to support the population when they get old AND medicare/medicaid increases 7x
China’s One Child Policy
They said a legal married age for males and females, contraceptives are free, and people are limited to having one child (except some circumstances Ex: twins)