1
There is no exception to the
rule that every organic
being increases at so high a
rate, that if not destroyed,
the earth...
We have an over population
problem and something needs to
be done to solve it.
A. Strongly agree
B. Agree
C. Neutral
D. Di...
3
V
4
5
Elephants
Starts breeding when 30 years old
Breeds until 90 years old
Has three pair of young
At the end of 500 years
15...
6
Even slow breeding man has doubled
in twenty-five years, and at this rate,
in a few thousand years, there would
literall...
World Population Estimates
Milestones
Year World
Population
1804 1 billion
1927 2 billion
1960 3 billion
1974 4 billion
19...
8
Human Overpopulation
Population Counter
9
Population Density (persons /
square km)
10
http://www.cbsnews.com/2300-500172_162-10010037-4.html
11
http://www.overpopulationmyth.com/
12
Dynamics of Population Growth
• Exponential
Growth - Growth at
a constant rate of
increase per unit
time. (Geometric)
•...
13
Carrying Capacity
• The maximum number of individuals of any species that
can be supported by a particular ecosystem on...
14
Environmental Resistance
• All the limiting factors that tend
to reduce population growth
rates and set the maximum
all...
15
16
17
Population Growth
• Until the Middle Ages, human
populations were held in check by
diseases, famines and wars, and thus...
18
• For most of our history, humans have not been very
numerous compared to other species.
• Before the invention of agri...
19
Human Population
• By 1650 the world population was about 600
million.
• After 1650 -- the age of science and the begin...
20
Blip on human trajectory
21
http://www.theguardian.com/world/2014/oct/28/global-population-science-growth-study-wars-disaster-disease
22
Scenario 1: BAU population growth (constant 2013 age-specific vital
rates);
Scenario 2a: reducing mortality, increasing...
23
Scenario 6: elevated childhood mortality from climate change
Scenario 7: mass mortality event over a 5-y period startin...
24
Limits to Growth
• Thomas Malthus (1798) argued human
populations tend to increase exponentially
while food production ...
25
Malthusian Trap
sarcozona.org
26
Karl Marx
• Population growth is a symptom rather than
a root cause of poverty and other social
problems.
– Real causes...
27
Malthus and Marx
28
The Role of Technology
• Technological optimists argue that Malthus
was wrong in his predictions because he
failed to a...
29
• http://www.gerrymarten.com/human-ecology/images/03-3-english.gif
What would you consider
yourself?
A. Malthusist (it’s a population problem)
B. Marxist (it’s a social problem)
C. Technolo...
31
http://www.census.gov/population/international/data/idb/worldpopchggraph.php
New wheat varieties and improved crop
mana...
32
http://www.bigpictureagriculture.com/2012/10/real-agricultural-prices-have-gone-down-as-population-has-headed-up.html
33
Can More People be
Beneficial ?
• More people mean larger markets,
more workers, and increased
efficiency due to mass p...
34
35
• Highest population growth rates
 Sub-Saharan Africa and the Middle East
◦ Niger, Yemen, and Palestine have an annual...
36
https://www.cia.gov/library/publications/the-world-factbook/geos/af.html
Growth Rate
37
Fertility and Birth Rates
 Fertility rates have
declined in every region
of the world except Africa
over the past 50 year...
39
Total Fertility Declines as
Women’s Education Increases
40
Birth Reduction Pressures
• Higher education and personal freedom
for women often result in decisions to
limit childbea...
Literacy Rates (Females)
41
http://world.bymap.org/LiteracyRatesFemales.html
99%
<25%
100%
88%
≈50%≈85%
Population Growth Rates
42
http://world.bymap.org/PopulationGrowthRates.html
+0.9%
+3.63%
-0.48%
Zimbabwe
http://www.index...
43
Population Growth, Opposing
Factors
• Pronatalist Pressures
– Factors that increase the desire for children.
• Source o...
Life Span and Life Expectancy
• Life expectancy- the average age that a
newborn infant can expect to attain in any
given s...
Life Span and Life Expectancy
45
46
Fluctuating Demographics
• In developing countries, higher
income often means families can
afford more children, thus f...
How many children are in your
family?
A. I am an only child (1)
B. I have one sibling (2)
C. I have two siblings (3)
D. I ...
48
Demographic Transition
http://www.susps.org/overvie
w/birthrates.html
49
Regions in the Process of
Demographic Transition
Crude Birth Rate - Number Births per thousand persons in a given year....
50
Demographic Transition
The Optimistic View
• Demographic transition is occurring in most
developing nations.
• Growing ...
51
Demographic Transition
The Pessimistic View
• The poorer countries of the world are caught in a
“demographic trap” that...
52
Source - United Nations - 1992
53
http://www.indexmundi.com/world/population_growth_rate.html
Doubling Time of a population: 70/annual percentage growth ...
Reduced Population Growth has
Demographic Implications
Both rapidly and slowly growing
countries can have a problem
with d...
55
56
http://www.census.gov/population/internat
ional/data/idb/informationGateway.php
57
58
Ice cubes, Frozen dinners, Green
beans, Spinach, or Eggs: Where is
your next food poisoning coming
from?
A. Ice Cubes
B. F...
of 59

Polulation2015(LorenEdit)

Published on: Mar 4, 2016
Source: www.slideshare.net


Transcripts - Polulation2015(LorenEdit)

  • 1. 1 There is no exception to the rule that every organic being increases at so high a rate, that if not destroyed, the earth would soon be covered by the progeny of a single pair. Population Dynamics
  • 2. We have an over population problem and something needs to be done to solve it. A. Strongly agree B. Agree C. Neutral D. Disagree E. Strongly Disagree 2
  • 3. 3 V
  • 4. 4
  • 5. 5 Elephants Starts breeding when 30 years old Breeds until 90 years old Has three pair of young At the end of 500 years 15 million elephants
  • 6. 6 Even slow breeding man has doubled in twenty-five years, and at this rate, in a few thousand years, there would literally not be standing room for his progeny. Charles Darwin 1859
  • 7. World Population Estimates Milestones Year World Population 1804 1 billion 1927 2 billion 1960 3 billion 1974 4 billion 1987 5 billion 1999 6 billion 2011 6.9 billion 2050 9 billion ???? Human Population Growth Wikipedia, 2011 7
  • 8. 8 Human Overpopulation Population Counter
  • 9. 9 Population Density (persons / square km)
  • 10. 10 http://www.cbsnews.com/2300-500172_162-10010037-4.html
  • 11. 11 http://www.overpopulationmyth.com/
  • 12. 12 Dynamics of Population Growth • Exponential Growth - Growth at a constant rate of increase per unit time. (Geometric) • Arithmetic Growth - Growth at a constant amount per unit time.
  • 13. 13 Carrying Capacity • The maximum number of individuals of any species that can be supported by a particular ecosystem on a long- term basis.
  • 14. 14 Environmental Resistance • All the limiting factors that tend to reduce population growth rates and set the maximum allowable population size or carrying capacity of an ecosystem.
  • 15. 15
  • 16. 16
  • 17. 17 Population Growth • Until the Middle Ages, human populations were held in check by diseases, famines and wars, and thus grew very slowly. – It took all of human history to reach 1 billion. – 150 years to reach 3 billion – 12 years to go from 5 to 6 billion • Human population tripled during the twentieth century.
  • 18. 18 • For most of our history, humans have not been very numerous compared to other species. • Before the invention of agriculture only a few million humans existed on the planet. • By 5000 BC the world population expanded to about 50 million. • By the first century AD the population reached 300 million. • Until the middle ages the human population was held in check by diseases, famines and war. Human Population Growth
  • 19. 19 Human Population • By 1650 the world population was about 600 million. • After 1650 -- the age of science and the beginning of modern transportation, technology and communication -- the population has increased rapidly. • In 2006 we had a world population of ~6.5 billion. • Will this explosion of growth continue until we overshoot the carrying capacity of our environment (if we have not done so already) and result in a catastrophic dieback?
  • 20. 20 Blip on human trajectory
  • 21. 21 http://www.theguardian.com/world/2014/oct/28/global-population-science-growth-study-wars-disaster-disease
  • 22. 22 Scenario 1: BAU population growth (constant 2013 age-specific vital rates); Scenario 2a: reducing mortality, increasing age at primiparity, declining fertility to two children per female by 2100; Scenario 2b: same as Scenario 2a but without reduced mortality; Scenario5: avoiding all unintended pregnancies resulting in annual births. High and low projections by the United Nations (12)are shown as a grayed area, and the revised range for 2100 http://www.pnas.org/content/early/2014/10/23/1410465111?tab=author-info
  • 23. 23 Scenario 6: elevated childhood mortality from climate change Scenario 7: mass mortality event over a 5-y period starting 2056, equal to the proportion of combined number of deaths from World War I, World War II, and Spanish flu scaled to the mid-21st century population Scenario 8: 2 billion people killed because of a global pandemic or war spread over 5 y, starting midway (i.e., 2056) through the projection interval; Scenario 9: 6 billion people killed because of a global pandemic or war spread over 5 y and initiated one-third of the way through the projection interval (i.e., 2041). The mass mortality windows are in-dicated as gray bars http://www.pnas.org/content/early/2014/10/23/1410465111?tab=author-info
  • 24. 24 Limits to Growth • Thomas Malthus (1798) argued human populations tend to increase exponentially while food production is plentiful. – Humans inevitably outstrip food supply and eventually collapse. • Human population only stabilized by positive checks. • Humans are too lazy and immoral to voluntarily reduce birth rates. • Growing human populations will only stop growing when disease or famine kills or when social conditions compel others to reduce their birth rates.
  • 25. 25 Malthusian Trap sarcozona.org
  • 26. 26 Karl Marx • Population growth is a symptom rather than a root cause of poverty and other social problems. – Real causes of these problems are exploitation and oppression. – The earth is bountiful in its resource base, but poverty and high birth rates results from oppressive social relationships that unevenly distribute wealth and resources. – The way to slow population growth and alleviate many social problems is through social justice.
  • 27. 27 Malthus and Marx
  • 28. 28 The Role of Technology • Technological optimists argue that Malthus was wrong in his predictions because he failed to account for scientific progress. – Current burst of growth was stimulated by the scientific and industrial revolutions. – Progress in agricultural productivity, engineering, medicine, sanitation, etc. have made it possible to support more people. – The burst of world population growth that began 200 years ago was stimulated by scientific and industrial revolutions.
  • 29. 29 • http://www.gerrymarten.com/human-ecology/images/03-3-english.gif
  • 30. What would you consider yourself? A. Malthusist (it’s a population problem) B. Marxist (it’s a social problem) C. Technological Optimist (wait, what problem?) D. I don’t agree with any of these. 30
  • 31. 31 http://www.census.gov/population/international/data/idb/worldpopchggraph.php New wheat varieties and improved crop management practices transformed agricultural production in Mexico during the 1940's and 1950's and later in Asia and Latin America, sparking what today is known as the "Green Revolution."
  • 32. 32 http://www.bigpictureagriculture.com/2012/10/real-agricultural-prices-have-gone-down-as-population-has-headed-up.html
  • 33. 33 Can More People be Beneficial ? • More people mean larger markets, more workers, and increased efficiency due to mass productions. • Greater numbers also provide more intelligence and enterprise to overcome problems. – Human ingenuity and intelligence.
  • 34. 34
  • 35. 35 • Highest population growth rates  Sub-Saharan Africa and the Middle East ◦ Niger, Yemen, and Palestine have an annual population growth rate is 3.2%. ◦ Less than 10% of all couples use any form of birth control, women average 7 children each, and nearly half of the population is less than 15 years old. • Negative growth rates – Italy, Germany, Japan, Hungary – Average age is 40, and by 2050 life expectancy is expected to exceed 90. Many couples have one or no children. – Japan is predicted to shrink from 127 million to 120 million by 2050. – Europe, which makes up 12% of the world population, is expected to drop to 7% by 2050. Africa’s population has tripled since 1960 and continues to grow the fastest. Europe had twice as many people as Africa in 1960. By 2050 experts estimate there will be three times as many Africans as Europeans.
  • 36. 36 https://www.cia.gov/library/publications/the-world-factbook/geos/af.html Growth Rate
  • 37. 37
  • 38. Fertility and Birth Rates  Fertility rates have declined in every region of the world except Africa over the past 50 years.  The greatest fertility reduction been in Southeast Asia, where rates have fallen by more than half.  The world as a whole has an average fertility rate of 2.6 and growth rates are now lower than at any time since WWII.Average total fertility rates for less-developed countries fell by more than half over the past 50 years. Progress slower in least-developed countries, but by 2050, they should be approaching the replacement rate of 2.1 children per woman. 38
  • 39. 39 Total Fertility Declines as Women’s Education Increases
  • 40. 40 Birth Reduction Pressures • Higher education and personal freedom for women often result in decisions to limit childbearing. – When women have more opportunities to earn a salary, they are less likely to have children. – Education and socioeconomic status are usually inversely related to fertility in wealthier countries.
  • 41. Literacy Rates (Females) 41 http://world.bymap.org/LiteracyRatesFemales.html 99% <25% 100% 88% ≈50%≈85%
  • 42. Population Growth Rates 42 http://world.bymap.org/PopulationGrowthRates.html +0.9% +3.63% -0.48% Zimbabwe http://www.indexmundi.com/g/g.aspx?c=zi&v=24
  • 43. 43 Population Growth, Opposing Factors • Pronatalist Pressures – Factors that increase the desire for children. • Source of pleasure, pride, comfort. • Source of support for elderly parents. • Current source of family income. • Social Status • Replace members in society as they die. –Boys frequently valued more than girls.
  • 44. Life Span and Life Expectancy • Life expectancy- the average age that a newborn infant can expect to attain in any given society. – The primary cause of most population growth in the past 300 years has been declining mortality, not increasing fertility. – 1900- average World-wide life span was 30 years 2009- average World-wide life span was 67 years 44
  • 45. Life Span and Life Expectancy 45
  • 46. 46 Fluctuating Demographics • In developing countries, higher income often means families can afford more children, thus fertility often increases. • In less-developed countries, adding another child to a family usually does not cost much, while in developed countries, raising an additional child can carry significant costs.
  • 47. How many children are in your family? A. I am an only child (1) B. I have one sibling (2) C. I have two siblings (3) D. I have three siblings (4) E. I have four or more siblings (5+) 47
  • 48. 48 Demographic Transition http://www.susps.org/overvie w/birthrates.html
  • 49. 49 Regions in the Process of Demographic Transition Crude Birth Rate - Number Births per thousand persons in a given year. Crude Death Rate Number of deaths per thousand persons in a given year.
  • 50. 50 Demographic Transition The Optimistic View • Demographic transition is occurring in most developing nations. • Growing prosperity and social reforms that accompany development reduce the need for large families. • Technology transfer to developing countries is progressing much faster than in the past. • Developing countries have historical examples to follow for population stability. • Modern communications is a stimulus for change and development.
  • 51. 51 Demographic Transition The Pessimistic View • The poorer countries of the world are caught in a “demographic trap” that prevents them from escaping from the present stage of demographic transition. • Their populations are growing so rapidly that human demands exceed the sustainable yield of local forests, grasslands, croplands or water resources. • The resulting environmental deterioration may prevent the developing world from completing modernization. • The developing world populations may continue to grow until catastrophe intervenes.
  • 52. 52 Source - United Nations - 1992
  • 53. 53 http://www.indexmundi.com/world/population_growth_rate.html Doubling Time of a population: 70/annual percentage growth rate. i.e. if the annual percentage growth rate is 35%, a population will double every 2 years.
  • 54. Reduced Population Growth has Demographic Implications Both rapidly and slowly growing countries can have a problem with dependency ratio. The number of non-working compared to working individuals in a population. By 2050, the UN predicts that there will be two older persons for every child in the world. Does this mean that some countries should re-think their population policies and/or offer incentives for marriage and child- bearing? 54
  • 55. 55
  • 56. 56 http://www.census.gov/population/internat ional/data/idb/informationGateway.php
  • 57. 57
  • 58. 58
  • 59. Ice cubes, Frozen dinners, Green beans, Spinach, or Eggs: Where is your next food poisoning coming from? A. Ice Cubes B. Frozen Dinners C. Green Beans D. Spinach E. Eggs

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