The Myth of the Sustainable Lifestyle
Michael J. Vandeman, Ph.D.
July 14, 2001
"Documenting human impacts on genetic diversity in forest trees and
other wildland plants is a difficult matter; little quantitative data
exist. Most evidence is anecdotal, and only in the extreme case of
extinction can we unequivocally demonstrate a reduction in diversity.
… Research is particularly needed to document changes in allele
frequency under various types of forest management; very few studies
exist on the impact of harvest methods on genetic diversity." (Ledig,
pp.87-8)
"Comparison of pre- and post-harvest gene pools indicated a
substantial loss of genetic diversity as a result of harvesting. … In
postharvest stand A about one-half of the 30 lost alleles were rare …
and one-half were low frequency alleles. … Eighty percent of all rare
alleles were lost from the two gene pools, whereas about 40% of all
low frequency alleles were lost. … 'Private' alleles, or those unique
to either stand A or stand B, were especially vulnerable to
harvest-induced elimination from the gene pools. … This suggests
genetic diversity losses of 25% or more may be common when forests of
this type are harvested at these intensities. … The loss of private
alleles from both stands gives concern for the integrity of
locally-adapted gene pools after harvesting." (Buchert et al,
pp.751-4)
"Sustainability" is the Holy Grail of the twenty-first
century. Everyone and his brother claim to have found it, or at least
to be able to describe what it would look like. We are told that
sustainable recreation, agriculture, fishing, hunting, and even
logging are within reach. But, like all such "campaign promises", they
aren't fulfilled, and, in fact, cannot be fulfilled!
In order to understand this, we first have to put the subject
on a solid foundation. "Sustainable" means "indefinitely repeatable,
without harm". Take "sustainable logging", for example. The
implication is that a proper method and rate of logging can be
continued forever, without diminishing the forest's resources -- in
other words, without harming it. It is implied (and usually not
explicitly stated) that the quantity of trees would be the same, with
or without logging. But if the logged species of tree would, absent
logging, naturally increase its population, holding it at a fixed
population would constitute a "harm" (at least from the point of view
of that species).
But population size is a rather subjective value. Humans are
very good at rationalizing any level they see as convenient. So let's
take a more concrete value: biodiversity, as exemplified by genetic
diversity. I think that biodiversity is a generally accepted value,
maybe even our highest value. Biodiversity supplies almost everything
that we like: satisfying, attractive foods, clean air, clean water,
effective medicines, beautiful places to live and recreate, etc.
Biodiversity is also finite. Although new (unique) genes are
continually being created, the rate of creation of new genes (that
survive) is far lower than the rate at which we are able to destroy
them. Thus, the number of different genes (or alleles) on the Earth is
a large, but finite, number. (By the way, the creation of new genes
does not "compensate" for the loss of other genes, except in a simple
mathematical sense; this is like comparing apples and oranges. The
creation of a new variety of apple doesn't "compensate" for the loss
of a variety of orange. We like the species that we have, and are not
consoled, upon their loss, by the creation of new ones.)
How does biodiversity get created? By mutation. Where does it
get created? In individuals. The very first time that a new gene (or
allele) is created, it most likely exists in a single individual. The
probability that the same genetic "accident" would happen
simultaneously in more than one individual is even lower than the
already low probability of its occurrence in the first individual.
Suppose, for example, that one of our to-be-logged trees contains a
mutation that would allow the species to survive global warming. Then
by killing even one tree, we could destroy biodiversity (a gene or
allele that exists nowhere else in the world), and have a significant
negative effect on the species!
Thus, logging (and any other killing of reproducing organisms)
can never be "sustainable": one can never guarantee that it won't
destroy a piece of that finite set, the world's store of genetic
biodiversity. Repeated often enough, it could, and probably would,
reduce the genetic diversity of the logged species, or even drive it
to extinction. If you continually destroy members of a finite set,
however large, it will eventually be empty. The probability of
destroying a unique gene may be low, but the consequences can be very
serious, so the killing of reproducing organisms must not be taken
lightly.
To bring this closer to home, look at the set of all humans,
alive or dead. (Assume that we have a concrete way of determining,
e.g. genetically, whether a given organism is a human being -- call it
gene H. Personally, I think that this distinguishing factor probably
involves a leap in memory capacity.) This is a finite set. Therefore,
it has a first member. There was a first organism having the H gene.
What if that first human were killed? Then it would be extremely
unlikely that humans would have evolved, at least in the relatively
short 6 (?) million years that we have been here.
Every biology textbook identifies "overharvesting" as one of
the major causes of the loss of biodiversity. However, as far as I
know, none of them define "over", and none of them discuss the loss of
biodiversity caused by harvesting that is not "overharvesting". If
they did, they would have to include the practice of "collecting"
(killing) organisms for scientific study. To the contrary, as recently
as 1979 (Wilkins and Peterson, p. 178), we find statements like
"Populations of wild animals can have the annual surplus cropped
without harm". Insect field guides, e.g. Powell and Hogue (1979),
recommend collecting insects as "an exciting and satisfying hobby for
anyone" (p. 359). An entomologist at the University of Phoenix told me
that collecting insects causes students to become excited about
studying biology. Okay, but I wonder how many of them end up
benefiting the species that they killed, and how many of them, on the
contrary, end up supporting practices (e.g. pest control) that harm
it? Is there really a net benefit to the organisms whose lives are
sacrificed to research? I doubt it.
Promoting the collecting of living organisms, besides teaching
biology, also teaches people (nonverbally -- the most powerful way of
teaching) that the killing of other species is to be taken lightly,
and that human concerns take precedence over the lives and wishes of
those species. That learning goes on even if the teacher verbally
expresses regret over the need to kill. (If a smoking parent tells his
children not to use drugs, what do the children actually learn?) Who
knows what other consequences it may have?
My intention, however, is not to single out any one form of
killing, but to explain why there can be no such thing as a
sustainable lifestyle: we all kill to eat, and therefore we risk doing
significant harm. At a minimum, the killing of living organisms,
especially reproducing organisms, should never be taken lightly.
Furthermore, the notion of a "sustainable yield" is a myth. It assumes
that the preservation of species is all that is important, and ignores
loss of diversity below the species level.
And there are other reasons why sustainability is
unattainable: for example, all organisms produce wastes that are
incompatible with their own existence. Trees produce oxygen. That
seems like a good thing, but oxygen is poisonous to many organisms.
And if there weren't mechanisms to remove excess oxygen from the
atmosphere, all of our forests would spontaneously combust ("An
increase in oxygen of only 4 percent could ignite the entire
atmosphere", James Lovelock in Newbold, p.9). I also wonder what would
happen to species of trees whose fallen leaves (and dead ancestors)
were not broken down by animals and fungi. So even a tree can't
sustain itself without the help of other organisms.
I think that the best we can say about sustainability is that
it is a worthy goal, approachable, but not actually attainable.
References:
Aczel, Amir D., The Mystery of the Aleph -- Mathematics, the Kabbalah,
and the Search for Infinity. New York: Four Walls Eight Windows, 2000.
Buchert, George P., Om P. Rajora, James V. Hood, and Bruce P. Dancik,
"Effects of Harvesting on Genetic Diversity in Old-Growth Eastern
White Pine in Ontario, Canada". Conservation Biology, Vol. 11, No. 3,
June 1997, pp.747-758.
Ehrlich, Paul R. and Ehrlich, Anne H., Extinction: The Causes and
Consequences of the Disappearances of Species. New York: Random House,
1981.
Knight, Richard L. and Kevin J. Gutzwiller, eds. Wildlife and
Recreationists. Covelo, California: Island Press, c.1995.
Ledig, F. Thomas, "Human Impacts on Genetic Diversity in Forest
Ecosystems". Oikos, Vol. 63, 1992, pp.87-108.
Liddle, Michael, Recreation Ecology. Chapman & Hall: London, c.1997.
Myers, Norman, ed., Gaia: An Atlas of Planet Management, Garden City,
NY: Anchor Books, 1984.
Newbold, Heather, ed., Life Stories: World-Renowned Scientists Reflect
on their Lives and the Future of Life on Earth. Berkeley: University
of California Press, 2000.
Noss, Reed F. and Allen Y. Cooperrider, Saving Nature's Legacy:
Protecting and Restoring Biodiversity. Island Press, Covelo,
California, 1994.
Powell, Jerry A. and Charles L. Hogue, California Insects. Berkeley:
University of California Press, c. 1979.
Stone, Christopher D., Should Trees Have Standing? Toward Legal Rights
for Natural Objects. Los Altos, California: William Kaufmann, Inc.,
1973.
Vandeman, Michael J., http://home.pacbell.net/mjvande, especially
"Wildlife and the Ecocity", "Rethinking the Impacts of Recreation",
and "Wildlife Need Habitat Off-Limits to Humans".
Ward, Peter Douglas, The End of Evolution: On Mass Extinctions and the
Preservation of Biodiversity. New York: Bantam Books, 1994.
Wilkins, Bruce J. and Steven R. Peterson, "Nongame Wildlife", in
Wildlife Conservation: Principles and Practices, Richard D. Teague and
Eugene Decker, eds. Washington, D. C.: The Wildlife Society, c. 1979.
Wilson, Edward O., The Diversity of Life. Cambridge, Massachusetts:
Harvard University Press, 1992.
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I am working on creating wildlife habitat that is off-limits to
humans ("pure habitat"😉. Want to help? (I spent the previous 8
years fighting auto dependence and road construction.)
Please don't put a cell phone next to any part of your body that you are fond of!