7       Ups and downs of Population

 

 

Prologue

“Human population growth has been so prodigious in recent centuries that it has also become a major driver of environmental deterioration, in the extent of pollution, consumption of natural resources, and destruction of habitats needed by other species.”

p. 140

Outline

     Overview

            the elephant in the living room” is the matter of population size

“Population genetics is concerned with changes through time in the composition of gene pools (all the genetic information possessed by a population), …; population dynamics or demographics … is about changes to the numbers of individuals and in the forces that produce these changes in a given population.” (140)

            an input-output system.” – see formulas { 141

.             Butterfly dynamics–checkerspot butterfly life cycles { 141

.    Human dynamics – 6.859 billion people July ‘10 { 142

.           Family Planning { 144

.        Curbing the population explosion { 146

.              The arithmetic of population growth { 149

.           Population pyramids { 151-52

.   Population momentum { 153

.        Aging populations { 155

 

 

Vocabulary 

Demography: fertility, mortality N>, rule of 70, doubling time, Fibonacci sequence, Infant death, contraception, migration, Malthusian dilemma,    exponential versus arithmetic growth, inverse square law, correlation.

 

Population distribution, graphs

Formulas

 

 

Population                            N – M + (Em Ī  Im) = P

 

                        Fertility minus mortally (plus or minus migration) equals population

 

Impact                                   I = P * A * T

                        Impact is equal to Population times Affluence time Technical capacity

 

Population History

 

French population change 1901-2001

 

Doubling time

The rule of 70

                                               % / 70 = TD

 

                                    percent ÷ 70 equals doubling time [TD]

 

The percentage of change divided by seventy (or seventy-two) is the time it takes for a quantity to double [TD].

 

 

Summary

“ . . . the problems that continued rapid global population growth is now bringing to the planet, that, in the view of the vast majority of knowledgeable scientists is already overpopulated.”

p. 157

 

US Bureau of the Census on line

 

The Encyclopedia of Earth

 

 

 

Population dynamics is the key to understanding the human reality of birth, death and migration as it impacts any region.

 

 

 

Understanding aggregate behavior of large numbers allows us to put cases of individuals and regional impacts into a more understandable perspective.

 

These are all linked with the Golden ratio through the Fibonacci sequence, which is given by

 

Four sequences
The differences among arithmetic, fibonacci, & exponential growth patterns.
A one two three four five six seven eight nine ten eleven twelve
F 1 1 2 3 5 8 13 21 34 55 89 144
Ex

1

2   4 8 16 32 64 128 256 512 1024 2048
difference 0 1 2 5 11 24 51          

U. S. Population

World Population

LANDSCAPE

Additional material

Merchant | Worster | Cronin | Reisner | Jackson | Siry | Leopold | Diamond | Williams | Austin | Mumford | Marx

 

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