16. Population Growth Flashcards
(32 cards)
How many individuals born/die per second.
4 born, 2 die.
Net gain per second
2.3
Net gain per year
72 million
Exponential Growth
=deltaN/deltat
=rN
r=birth rate - death rate
N=number of individuals reproduced
Logistic Growth
rN((K-N)/K
K=carrying capacity
N>K then G is positive
Most common
2 things limiting population growth
Density independent factors and density dependent factors
What are density independent factors
Climate like natural disasters, hurricanes etc.
What are density dependent factors
A factor having negative feedback on growth rate like food resources.
Total Fertility Rate (TFR)
number of individuals born on average during a woman’s reproductive life
Replacement Level of TFR
2.06, the population is stationary
Doubling Time
0.7/r
The time it takes for a population to double in size
What countries have the highest fertility rate
Developing countries
How many individuals are predicted in 2050 in the world
9 billion
Where is growth expected to be greatest in?
Developing countries
What are the two demographic worlds?
Developing countries and developed countries
Factors determining fertility rate
Cultural
Demographic
Economic
Political
Demographic Transition Model
All societies go through progression.
Expect decline in birth and death rates.
Stages: 1. Pre-industrial 2. Transition 3 industrial 4. Post-industrial
Perspectives on human population growth
Optimistic Economist Pessimist Technologist Social Justice Ecologist
Optimistic Economist
World population will stabilize due to demographic transitions
Pessimist
Demographic transitions may not occur in developing countries
Technologist
Technology will save us
Social Justice
Population growth is the symptom not the problem
Ecologist
Population growth is the problem. We’ll go over the carrying capacity if everyone goes through demographic transition the way developed countries did.
Age structure in the USA
Pig in the python Pig=baby boom 8 million born Fertility rates dropped 3-2 Medicaid and Medicare increased 7x in the next 4 decades.
