Population Theories

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Population Theories
Malthus and Boserup
Critical Comparison and Application
Dr. Manish Kr. Semwal
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Malthus (1766-1834)
• A mathematician, a clergyman, and Britain’s
first professor of political economy
• Known as “father of demography”
• One of the most influential thinkers of his day,
which was a period of improved social change,
Industrial Revolution, idea less world
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Malthus’s An Essay on the
Principle of Population (1798)
• First edition proposed a quite stark & simple
model, & drew social policy conclusions from
it
• Perhaps for that reason, it had a dramatic
impact on public debates
• Second and later versions were more nuanced
in argument, much better supported
evidentially - & less interesting
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Malthus started from two assumptions
1. Food is necessary for survival
2. “The passion between the sexes is necessary
and will remain in its present condition”
• From these he asserted that population
growth would always have the potential to
outpace economic growth
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Malthus’ Theory of Population Growth
• In 1798 Thomas Malthus published his views on
the effect of population on food supply. His
theory has two basic principles:
• Population grows at a geometric rate i.e. 1, 2, 4,
16, 32, etc.
• Food production increases at an arithmetic rate
i.e. 1, 2, 3, 4, etc.
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• The consequence of these two principles is that
eventually, population will exceed the capacity of
agriculture to support the new population
numbers. Population would rise until a limit to
growth was reached. Further growth would be
limited when:
– preventive checks - postponement of marriage
(lowering of fertility rate), increased cost of food etc.
– positive checks - famine, war, disease, would increase
the death rate.
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Population grows geometrically….
Population exceeds carrying
capacity…
Population is kept in “check”–
preventative and/or positive
checks
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Proposed Solutions
• Two types of checks hold population within
resource limits:
• positive checks: which raise the death rate;
hunger, disease and war.
• preventative checks: which lower the birth
rate; abortion, birth control, prostitution,
postponement of marriage and celibacy.
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Thus some ‘check’ must limit population
growth
• Accordingly, Malthus saw two ways to keep
population and resources in balance1: the ‘positive check’ – mortality; deaths
2: the ‘preventive check’ – nuptiality;
marriages, or rather constraints on them
• He ruled out contraception as immoral
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Positive and preventive checks
•
•
•
•
Positive check
Population size rises
Real income falls
Mortality increases
(poorer diets & living
conditions)
• Population size falls
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•
•
•
•
Preventive check
Population size rises
Real income falls
Marriages are
postponed (they
become unaffordable)
• Fertility falls
• Population size falls
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Limitation- Access to relevant data
• Economic history (Phelps-Brown & Hopkins) &
historical demography (Wrigley & Schofield) now
allow a much fuller assessment of, say, the
English historical data than Malthus himself could
make
• P-B & H produced real wages index based on
wages of building workers & price of food
• W & S inferred demography from parish registers
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Thus Malthus was in a way successful
• But his model took some aspects of society,
economy, agriculture etc. as static
• They were then undergoing rapid change, so his
model described the past better than the future
• This is perhaps partly why he has subsequently been
seen as conservative
• ‘Malthusian’ sometimes even used to mean
‘opposed to social improvement’
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Need to incorporate social change in
population models: at present
• What is the role of population dynamics in
situations of complex social, economic &
technological change?
• Such situations may be those of globalization
in the present day
• Economic development, modernization
• 19th-century industrialization even in
developing countries.
• Earlier changes: agriculture & urbanization
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Boserup
The Conditions of Agricultural Growth: The
Economics of Agrarian Change under Population
Pressure 1965
• Danish agricultural economist, with field
experience in India & other Asian countries
• Interested in the interaction between
population growth and innovation, e.g. in
agricultural practice & technology
• Although neither a demographer nor an
anthropologist or archaeologist, she has
proved to be an important influence on all
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Archaeological background
• How does past population growth relate to
social, cultural, economic, technical change,
e.g. agriculture, urbanization?
• Archaeologists e.g. Childe had often taken the
benefits of such changes to be obvious
• Assumed they would be implemented as soon
as society was advanced enough
• Population growth would then follow
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Boserup & archaeology
• Boserup’s implication for archaeology was to
turn previous assumption on its head
• Population growth was not so much the endproduct of social & technical change
• Rather, population growth was an extrinsic
pressure, driving changes which otherwise
might not have happened
• Far-reaching implications for archaeology &
anthropology, still being explored
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Boserup’s Theory of Population Growth
• In contrast to Malthus, instead of too many mouths
to feed, Boserup emphasized the positive aspects of a
large population;
• In simple terms, Boserup suggested that the more
people there are, the more hands there are to work;
• She argued that as population increases, more
pressure is placed on the existing agricultural system,
which stimulates invention;
• The changes in technology allow for improved crop
strains and increased yields.
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Increased Food Production
•
•
•
•
•
•
•
•
Draining Marshlands.
Extensification.
Intensification.
Reclaiming land from sea.
Cross-breeding cattle.
High-yield plant varieties.
Terracing on steep slopes.
Fish farming.
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• Growing crops in
greenhouses.
• More sophisticated
irrigation techniques.
• Creation of new foods such
as soy.
• Using artificial pesticides.
• New species
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So what did Boserup actually say?
• When a population is over-crowded, it evolves
new forms of agriculture
• High density of population is neutral, neither
good nor bad, but usually needed for
development of new techniques
• With historical change, humankind has moved
through a series of increasingly intensive
agricultural systems
• Each requires & supports more people
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Testing Boserup
• No long-run data series like Wrigley &
Schofield’s for Malthus is available for testing
Boserup’s model
• Nonetheless specific examples often support
the propositions such as: farmers generally
have to do more subsistence work than
hunter-gatherers; work further increases with
intensification of agriculture
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Malthus and Boserup
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Present Situation
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Anti-populationists vs. pronatalists
• Malthus– anti-populationist
– Echoed in recent debates by Paul Ehrlich, author of
The Population Bomb;
– Ehrlich believed that the earth’s carrying capacity
would quickly be exceeded, resulting in widespread
famine and population reductions;
• Boserup– pronatalist (cornucopian)
– Echoed in recent debates by Julian Simon, who
opposed Ehrlich by using economic theories; ie.
Resources needed to support populations are
becoming more abundant, not scarcer;
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Malthus & Boserup
• There is evidence to suggest that the ideas
of Malthus and Boserup may be
appropriate at different scales.
• On a global level the growing suffering and
famine in some LEDC’s may reinforce
Malthusian ideas.
• On a national scale some governments
have been motivated by increasing
populations to develop their resources to
meet growing demands.
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Case Study Example
Mauritius
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Location Map
Mauritius
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Map of Mauritius
Built up area
N
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Mauritius: Population Change
Population
1992: 1,094,000
2025: 1,365,000
Growth Rate: 1.45%
Pop doubling time:
47 years
Fertility Rate:
2.17 children
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Mauritius: Physical Geography
• Area: 1860 sq km
• Natural Resources: arable
land & fish
• Agriculture: a/c for 10%
GDP
• Climate: tropical
• Soils: fertile
• Exports: sugar 32%;
garments 31%; plastics
32%; others 5%
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The Issues?
1.What can we say
about the rate of
population growth in
Mauritius?
2. How does the graph
opposite contribute
to our understanding
of population growth
in Mauritius?
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Crisis? What Crisis?
Consider the graph
again. To what extent do
you agree with this
statement:
In the 1950’s Mauritius
was experiencing a
‘Malthusian crisis’
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Possible Answer!
• Birth rate had risen sharply from 35 to 45+
per thousand
• Death Rate had declined sharply from 30 to
15 per thousand
• Rate of natural increase suddenly very steep
PRESSURE ON THE ECONOMY/NATURAL
RESOURCES/AGRICULTURE
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Population Resources Equation
• Population increasing
• Diminishing resources (more mouths to
feed and more people to support)
POP’N
RESOURCES
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What happened next?
Malthus - doom & gloom?
OR
Boserup - ‘technological’ change
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Government Intervention
The Government organised a family planning
programme, aiming to:
• improve the status of women
• restrict early marriage
• provide better health care
• set up a family planning service
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Other influencing factors 1
• Changes in attitude to family size
• improved educational opportunities for
women
• improved female work opportunities (by 1990
35% of women were in paid employment
(22% in 1975))
• getting married later on in life
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Other influencing factors 2
• Diversification of agriculture
• Investment in industry
• Improved trading links - as an ex colony of
the UK it is quite ‘westernised’ and has a
democratic, stable Government - this has
helped forge links with the USA
• Many TNC’s are drawn to Mauritius - Why
might this be? Suggest some reasons!!!
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Mauritius - TNC Attractor!
• Holds ‘Export
Processing Zone’ (EPZ)
status
• Good level of
investment in transport
• Tax incentives available
• Good supply of cheap
labour
• Has large numbers of
well educated residents
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• The creation of a
Freeport at Port Louis
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Population Resources Equation
POPULATION
RESOURCES
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Thank You
Manish Kr. Semwal
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