HAVE FORTY YEARS LEFT TO INVENTORY WORLD'S BIODIVERSITY
January 27, 2002
Ten years ago, my column started with the following: "We have a dilemma
to deal with. During the next thirty years the human population in tropical
countries could double. Meanwhile, 20% or more of the plant and animal
species that inhabit these countries will probably vanish."
The column was based on an article in Science magazine by Peter H. Raven
of the Missouri Botanical Garden and Edward O. Wilson of Harvard University,
who stated that we need a global effort "to map biodiversity in order
to plan its conservation and practical use." They made a case that
we need to determine where all species live, how we can assure their survival,
and what value each might have for our own species. Shortly after that
the Department of Interior's National Biological Survey (NBS) was created.
Both ideas were good ones and still are. But shortly after that, congressional
members associated with the "Contract for America" abolished
But no matter which direction political winds blow, biodiversity will
always be an indicator of and contributor to ecosystem health and resiliency.
When we destroy or remove plants and animals from a region, even on a
local scale, we lose biodiversity. Even if species extinction does not
occur, the loss of genetic information is permanent. Lowering biodiversity
in a habitat has an impact on the entire ecosystem by affecting interactions
among different species.
Raven and Wilson pointed out that habitat destruction was a primary cause
of the rapid disappearance of the world's biodiversity. The same is true
today, except that we now have less to lose because much is already gone.
One estimate was that 1% of the species in tropical systems become extinct
every two years, meaning we may have lost a sizable number since that
time. Coral reefs, high diversity marine habitats, were viewed as being
in major trouble because of pollution and habitat alteration. The same
is as true or more so today.
Some people may shrug at the disappearance of exotic animals and plants
they will never see. They should not. Each gene within a species is a
unique storehouse, a treasure chest of biochemical information. Numerous
rationales and justifications exist for preserving the endless array of
intricate biological relationships and delicate ecological balances even
for species we may never personally encounter.
Yet undiscovered plants, animals, and microorganisms may harbor medical
secrets that can benefit humankind. Some may have potential as new sources
of food or energy. Others may already serve, unnoticed, as biological
controls of pest species, as essential biological partners with species
we consider important. Some may be ecologically important detoxifying
agents. Plants, soil microbes, and the lowly earthworm are critical in
the manufacture, aeration, and maintenance of soils throughout the world.
The tropical rain forests alone have a global influence on climate. Reducing
the number of species in an ecosystem diminishes the overall effectiveness
of the world's organisms in performing these vital roles. And we seldom
know which species are most critical for maintaining the integrity of
Raven and Wilson proposed a fifty-year plan for systematic inventories
of the species inhabiting all regions of the world, a global biodiversity
survey. Approximately one and half million living species have been discovered,
but by some estimates from five to fifty times as many are undiscovered.
The authors recommended a program of national biological surveys throughout
the world and made it clear that we have little time to lose.
Their proposal targeted the scientific community, but such an effort must
also have public support acquired through environmental education of children
and adults. And then we must all educate politicians. An environmentally
educated society cannot plead ignorance about whether we should assure
the welfare of natural environments by maintaining the world's biodiversity.
Each of us can contribute to the protection of the world's ecosystems
by convincing others that in addition to potential value for us, each
species has its own intrinsic value, its own right to exist.
Ten years ago our country failed to follow through on the plan for surveying
our national biodiversity. Let's not wait until we've run out of time.
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