BIOS 3010: Ecologyhomepages.wmich.edu/~malcolm/BIOS3010-ecology/Lectures/L24-Bios3010.pdfpopulation x consumption per person x the amount of resources needed or wastes created producing

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BIOS 3010: Ecology Dr. S. Malcolm Lecture 24: Slide - 1

•  Lecture summary:

– Scientific method. – Parsimony and

hypotheses. –  Induction and

deduction. – Asymmetry between

science and politics. – Abundance-catastrophe

debate.

BIOS 3010: Ecology Lecture 24: Abundance or catastrophe


2. How do we do science:

•  Pattern and process: – Observable patterns. – Processes that generate the patterns.

•  Proximate and ultimate causes: – Proximate - superficial causes of

observable patterns. – Ultimate - underlying causes:

• The processes that generate observable patterns.


3. Parsimony and hypothesis generation:

•  Parsimony means economy of explanation: –  Use Ockham’s philosophical razor to shave away

unecessarily complicated explanations! •  The simplest testable explanation for

observations: –  Start with the simplest hypothesis as a null of no

effect. –  If this can be rejected then test the next most simple

hypothesis that invokes causality. –  Move through successive hypotheses up a hierarchy

of complexity.

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4. Inducible and deducible causality:

•  Induction: –  Invokes biased preference and subjectivity:

•  Often implies political correctness at the expense of truth.

•  Deduction: –  Invokes objectivity:

•  The rational and logical process of hypothesis testing up a hierarchy of explanations characterized by decreasing parsimony and increasing complexity.


5. Environmental issues:

•  Usually invoke considerable subjectivity because of asymmetry:

–  Asymmetry between scientific method and political will.

–  Asymmetry exists because of poor scientific education among politicians: •  Environmental science is highly complex and hard to

communicate. •  There are rarely simple solutions to environmental issues. •  Politicians have little incentive to understand environmental

issues unless they have direct relevance.


6. Environmental relevance:

•  Direct: – Pollution in your backyard is easy to see and

establish responsibility. –  Impact of Rachel Carson and Silent Spring.

•  Indirect: – Pollution from unknown sources is hard to

understand and assign responsibility. – Role of the Environmental Protection

Agency and implementation of legislation.

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7. Environmental controversy:

•  These simple facts lead to environmental controversy such as the polarized abundance-catastrophe debate:

–  Economist Julian Simon argued persuasively for resource abundance that drives economic growth and human success. •  Ideas reinforced by Danish statistician B. Lomborg in 2001.

–  Ecologist Paul Ehrlich argues equally persuasively for impending catastrophe based on a Malthusian view of exponential human population growth outpacing the geometric increase in resources and technology.


8. Ehrlich & Holdren (1974) Science 171:1212

•  Impact = Population x Affluence x Technology I = P x A x T

•  Environmental impact is the product of population x consumption per person x the amount of resources needed or wastes created producing each unit of consumption.

•  So population is the dominant factor in environmental damage.


9. Julian Simon (1932-1998):

•  “This is my long-run forecast in brief: The material conditions of life will continue to get better for most people, in most countries, most of the time, indefinitely. Within a century or two, all nations and most of humanity will be at or above today’s Western living standards. I also speculate, however, that many people will continue to think and say that the conditions of life are getting worse.” –  Julian Simon (1932-1998), Professor of Economics, University of

Maryland (Regis 1997:198) - quote from the front of Lomborg (2001)

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Lomborg (2001) Fig. 20: Prevalence of infectious diseases in the US 1900-98.


Lomborg (2001) Figs 23 and 24: Daily intake of calories per capita 1961 - 98 (left) and proportion of people starving 1970-2010 (right).


Lomborg 2001 Figs 25 and 26: Wheat price index in England 1316-2000 (left) and World bank price index for foodstuffs (right).

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Abundance & catastrophe:

•  Harrison & Pearce (2000) page 8: –  Resource abundance figure from Simon (1996) and collapse predicted

by one of the models in Meadows et al. (1992).


William of Ockham:

•  Or William of Occam •  Born near Guildford in Surrey in 1285 •  Thought to have said:

–  “Non sunt multiplicanda entia praeter necessitatem”

•  Entities are not to be multiplied beyond necessity.

–  Used this principle so frequently and sharply that it became known as “Ockham’s razor”

•  Brilliant Franciscan monk who annoyed both Oxford University and the Pope (excommunicated as a heretic by Pope John XXII).

•  Died of the plague in about 1349 in the service of Emperor Louis of Bavaria (1328-1349).


References:

•  Ehrlich, P.R., & A.H. Ehrlich. 1990. The population explosion. Simon & Schuster, New York.

•  Harrison, P., & F. Pearce. 2000. AAAS atlas of population & environment. University of California Press, Berkeley.

•  Lomborg, B. 2001. The skeptical environmentalist. Measuring the real state of the world. Cambridge University Press, Cambridge.

•  Meadows, D.H., D.L. Meadows & J. Randers. 1992. Beyond the limits: confronting global collapse, envisioning a sustainable future. Chelsea Green Publishing Co., White River Junction, Vermont, 300 pages.

•  Simon, J. 1996. The ultimate resource 2. Princeton University Press, New Jersey.

BIOS 3010: Ecologyhomepages.wmich.edu/~malcolm/BIOS3010-ecology/Lectures/L24-Bios3010.pdfpopulation x consumption per person x the amount of resources needed or wastes created producing

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