THEORIES OF POPULATION GROWTH

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THEORIES OF POPULATION GROWTH

• Thomas Malthus
• malthusian checks
• William Catton
• carying capacity
• D.J. Bogue
• demographic regulation

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THOMAS MALTHUS
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Who is Thomas Malthus?

• English economist - 1766 to 1834
• Witnessed huge population increases in European
  cities (England) due to Industrial Revolution.
• Wrote An Essay on the Principle of Population
  (1798) in which he argued that populations grow
  geometrically but food supply only
  arithmetically.
• Was one of the first to warn against the dangers
  of population growth
• Population would soon outstrip food supply.
• Overcrowding led to inadequate housing, lack of
  sanitation, widespread crime and other social
  ailments

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Malthusian Checks

• As hunger increased there would be more social
  disorder, riots, wars, plagues - famine.
• Malthus believed that if left unchecked, the
  rapidly growing population would destroy the
  quality of life
• Malthus believed that the human population had
  the ability to double ever generation (approx. 25
  yrs)
• Argued that moral restraint was only hope no
  premarital sex, later marriages.

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Food supply Population 1 1 2 2 3
4 4 8 5 16 etc.
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Problems with Malthusian Theory

• Malthus predictions did not materialize
• Birth rates declined soon after death rates did.
  Contraception became more widespread.
• Industrialization and urbanization meant less
  need for family labour.
• Population did not double every 25 years
• Cultivation of new territories in the Americas
  and Australia also added to the food supply

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• Better health (public and personal hygiene and
  better food) meant lower death rates.
• More children survived people lived longer.
• Child labour laws and mandatory schooling laws
  meant child had to be supported far longer.
• Children became economic liabilities instead of
  assets.
• Family size shrank.
• Nonetheless Malthusian theory is still relevant
• Many economists believe the time will come when
  natural systems will no longer be able to support
  the worlds population

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Many economists believe the time will come when
natural systems will no longer be able to support
the worlds population

• Darfur?
• AIDs?

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Darfur a Case Study
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Background

• The dire situation in Darfur dates back to March
  2003
• Sudan Liberation Army (SLA) accused President
  Omar Hassan El-Bashir of neglecting the region
  and oppressing black Africans in favour of Arabs
  in the state of Darfur.
• The two sides met in armed conflicts since this
  time and more than 200,000 people have been
  killed while another200,000 have fled to Chad.
• Arab militias, with links to the government,
  have destroyed food and water resources in West
  Darfur, Sudan.
• Governments have warned of possible genocide in
  the region

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Famine

• Darfur may well be the first war influenced by
  climate change
• In recent years, increasing drought cycles and
  the Sahara's southward expansion have created
  conflicts between nomadic and sedentary groups
  over shortages of water and land

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• Climate change, population growth, rising
  consumption patterns and globalization are all
  contributing to the phenomenon
• In places like Africa the infrastructure and the
  government are weak
• This allows pressures to multiply and creates
  conflicts and schisms
• These conflicts often occur along religious or
  tribal lines since that is how society is
  organized

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Population

• Like most African nations Sudan is experiencing
  high levels of population growth
• Natural Increase 2.6
• Population is expected to double by 2050

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William Catton

• Catton wrote Overshoot The Ecological Basis of
  Revolutionary Change which examined current
  population trends
• Catton coined the term carrying capacity
• People accused him of being a neo-Malthusian
  (attempting to revive Malthus theory)
• Carrying capacity is defined as the number of
  people a given environment can support
  indefinitely
• Therefore the needs of the population are
  balanced against the health of the environment

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Can the world carry an increasingly affluent
Population?

• Catton believed that European expansion into
  under populated areas of the Western and Southern
  Hemispheres in the sixteenth and seventeenth
  centuries, laid the foundation for todays
  population crisis
• Once growth and prosperity became common, people
  expected the spiral to continue
• This led to the drawing down of non-renewable
  resources (stealing of resources from future
  generations)
• Catton argues that once the earths non-renewable
  resources are gone, the earths carrying capacity
  will drop dramatically

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D.J. BOGUE

• Writing in the 1960s, D.J. Bogue described what
  he called the theory of demographic regulation
• Meaning, over an extended period of time society
  naturally limits its population.
• Population will only grow if the Earth is able to
  support it.
• The population explosion of the last 150 years
  may lead people to believe that this theory does
  not work, however supports of demographic
  regulation believe that the industrial revolution
  has dramatically raised Earths carrying
  capacity, and the worlds population has been
  adjusting to this increase.
• Sweden has completed this process, while for a
  country like Mexico this process continues

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Examples of Demographic Regulation