1988
The Planet
BY EUGENE LINDEN
Jan. 3, 1989
Before Brazil's great land rush, the emerald rain forests of Rondonia
state were an unspoiled showcase for the diversity of life. In this lush
territory south of the Amazon, there was hardly a break in the canopy of
200-ft.-tall trees, and virtually every acre was alive with the cacophony of
all kinds of insects, birds and monkeys. Then, beginning in the 1970s, came the
swarms of settlers, slashing and burning huge swaths through the forest to
create roads, towns and fields. They came to enjoy a promised land, but they
have merely produced a network of devastation. The soil that supported a rich
rain forest is not well suited to corn and other crops, and most of the
newcomers can eke out only an impoverished, disease-ridden existence. In the
process, they are destroying an ecosystem and the millions of species of plants
and animals that live in it. An estimated 20% of Rondonia's forest is gone, and
at present rates of destruction it will be totally wiped out within 25 years.
Around the globe, on land and in the sea, the story is much the same.
Spurred by poverty, population growth, ill-advised policies and simple greed,
humanity is at war with the plants and animals that share its planet. Peter
Raven, director of the Missouri Botanical Garden, predicts that during the next
three decades man will drive an average of 100 species to extinction every day.
Extinction is part of evolution, but the present rate is at least 1,000 times
the pace that has prevailed since prehistory.
Even the mass extinctions 65 million years ago that killed off the
dinosaurs and countless other species did not significantly affect flowering
plants, according to Harvard biologist E.O. Wilson. But these plant species are
disappearing now, and people, not comets or volcanoes, are the angels of
destruction. Moreover, the earth is suffering the decline of entire
ecosystems—the nurseries of new life-forms. For that reason, Wilson deems this
crisis the "death of birth." British ecologist Norman Myers has called it the
"greatest single setback to life's abundance and diversity since the first
flickerings of life almost 4 billion years ago."
Nearly every habitat is at risk. Forests in the northern hemisphere have
fallen to lumbering, development and acid rain. Marine ecosystems around the
world are threatened by pollution, overfishing and coastal development. It is
in the tropics, though, that the battle to preserve what scientists call
biodiversity will be won or lost. Tropical forests cover only 7% of the earth's
surface, but they house between 50% and 80% of the planet's species.
But should people in developed countries care about the survival of
tropical species never seen outside a rain forest? Yes, they should. Variety is
the spice of life, goes the saying. Biologists would go further and argue that
variety is the very stuff of life. Life needs diversity because of the
interdependencies that link flora and fauna, and because variation within
species allows them to adapt to environmental challenges. But even as the
world's human population explodes, other life is ebbing from the planet.
Humanity is making a risky wager—that it does not need the great variety of
earth's species to survive.
Despite the alarm with which scientists view this trend, biodiversity has
just surfaced on the world's political agenda. The troubles of high-profile
animals such as the tiger and rhino grab public attention, while most people
hardly see the point of worrying about insects or plants. But extinction is the
one environmental calamity that is irreversible. As these lowly species
disappear unnoticed, they take with them hard-won lessons of survival encoded
in their genes over millions of years.
Only 1.7 million of the estimated 5 million to 30 million different
life-forms on earth have been cataloged. Since hundreds of thousands of species
may be extinct by the year 2000, the world has neither the scientists nor the
time to identify the yet uncounted. "It's as though the nations of the world
decided to burn their libraries without bothering to see what is in them," said
University of Pennsylvania biologist Daniel Janzen at the TIME conference.
Harvard's Wilson called this profligacy the "folly" that future generations are
least likely to forgive.
Humanity already benefits greatly from the genetic heritage of
little-known species. Some 25% of the pharmaceuticals in use in the U.S. today
contain ingredients originally derived from wild plants. Hidden anonymously in
clumps of vegetation about to be bulldozed or burned might be plants with cures
for still unconquered diseases. "I know of three plants with the potential to
treat AIDS," said Janzen. "One grows in an Australian rain forest, one in
Panama and one in Costa Rica."
Nature's diversity offers many opportunities for agriculture, especially
now that genetic mapping and engineering have given biotechnology firms the
potential power to improve crops by transferring genes from wild strains.
According to Wilson, biotechnology can transform a plant into a "loose-leaf
notebook" from which scientists can select a particular page. Among the
possible results: drought- and frost-resistant crops, and natural fertilizers
and pesticides.
Diversity is the raw material of earth's wealth, but nature's true
creativity lies in the relationships that link various creatures. The coral in
a reef or the orchid in a rain forest is part of an ecosystem, a fragile, often
delicately balanced conglomeration of supports, checks and balances that
integrate life-forms into functioning communities. Given the complex workings
of an ecosystem, it is never clear which species, if any, are expendable.
In the tropics the crucial question is how large a forest must be to
sustain itself. If a park or protected area is too small to support some of its
animal and plant life, the ecosystem will decline even with protection. As yet,
no one knows the minimum critical size of a rain forest, but in 1979 Thomas
Lovejoy, now at the Smithsonian Institution, set up a 20-year experiment with
the cooperation of the Brazilian government to determine just that for the
Amazon region. Among the findings: the smaller the forest, the faster the
decline of insects, birds and mammals.
Biologists have identified numerous "hot spots" where ecosystems are under
attack and large numbers of unique species face an immediate threat of
elimination. Among the troubled areas: Madagascar, where more than 90% of the
original vegetation has disappeared; the monsoon forests of the Himalayan
foothills that are being denuded by villagers in search of firewood, building
materials and arable land; New Caledonia, 83% of whose plants occur nowhere
else; the eastern slope of the Andes, as well as forests in East Africa,
peninsular Malaysia, northeast Australia and along the Atlantic coast of
Brazil.
Since less than 5% of the world's tropical forests receive any protection,
the stage is set for mass extinctions. Many plants and animals are doomed, no
matter what measures are taken. Some researchers estimate that at least 12% of
the bird species in the Amazon basin, as well as 15% of the plants in Central
and South America, can be counted among what Janzen calls the "living dead."
Many tropical mammals and reptiles face only bleak survival under what amounts
to house arrest in game parks and zoos.
Why are so many species and environments threatened? The main reason is
that throughout the tropics, developing nations are struggling to feed their
peoples and raise cash to make payments on international debts. Many countries
are chopping down their forests for the sake of timber exports. In Central
America forests are giving way to cattle ranches, which supply beef to American
fast-food chains. The pressures on forests have led Janzen, who has spent 26
years struggling to save Costa Rica's woodlands, to conclude that "everything
outside parks will be gone, and everything inside the parks is threatened."
Efforts to stop the destruction run into moral as well as practical
obstacles. How can developed nations demand onerous debt payments and ask the
debtors to preserve their forests? How can countries worry about biodiversity
when their people are concerned with feeding themselves?
To begin with, the rich nations must reduce the debt burden of the poor.
But just as important is a concerted campaign to convince the people of
developing countries that it is in their own long-term interest to preserve
their environments. Wiping out forests may make developing nations momentarily
richer, but it is bound to produce a poorer future.
Experience has shown the Third World that destruction of forests can have
disastrous consequences. Forests are vital watersheds that absorb excess
moisture and anchor topsoil. Deforestation contributed to the recent droughts
in Africa and the devastating mud slides in Rio de Janeiro last year. In Costa
Rica topsoil eroded from bald hills has greatly shortened the life of an
expensive hydroelectric dam. Alvaro Umana, Costa Rica's Minister of Industry,
Energy and Mines, estimated that the surrounding watershed might have been
protected 20 years ago for a cost of $5 million. Now the government must
reforest the watershed at ten times that price.
Halting the assault on biodiversity will not be easy, but there are many
actions that governments can take. First, they should develop and support local
scientific institutions that train professionals in conservation techniques.
More money should flow into educational programs that alert people to the
irreversible consequences of a loss of genetic diversity. An international,
environmental version of the Peace Corps could spread conservation expertise to
the Third World.
Throughout the developing nations there are encouraging stirrings of local
environmental activity. In Malaysia blowgun-armed Penan tribesmen have joined
forces with environmentalists in an effort to stop rampant logging. And in
Brazil, which has some 500 conservation organizations, environmentalist Jose
Pedro de Oliveira Costa organized a coalition of legislators, conservationists,
industrialists and media barons to stir public support to preserve Brazil's
remaining Atlantic forests. "The threats to the forests remain," said Costa,
"but now at least there is a network in place to scream when a threat arises."
But environmental protection must make economic sense, and development
must go hand in hand with preservation. Development should be sustainable,
meaning that it should use up resources no faster than they can be regenerated
by nature. Governments and private firms should organize projects to show that
forests can be used without being obliterated. If trees are cut selectively,
forests can yield profits and survive to produce more money in the future.
Another way to harvest cash from forests and other habitats is to set up tours
and safaris to attract animal lovers and photography buffs. Long a moneymaker
in Africa and the Galapagos Islands, this "ecotourism" is spreading to such
places as Costa Rica.
For sustainable development to work, observed Paulo Nogueira-Neto,
environmental adviser to the Brazilian Ministry of Culture, governments will
have to devise comprehensive national zoning plans so that their countries can
achieve the right mix of preservation and economic growth. Local residents can
be encouraged to earn a livelihood in the more robust areas, while habitats
that are fragile can be protected. Sustainable development can proceed, noted
Kenneth Piddington, director of the environmental department of the World Bank,
"right up to a park's boundary."
Financial as well as political leverage can be used in the cause of
preservation. Governments should force local lending institutions to review the
environmental consequences of proposed loans. No bank, for example, should be
allowed to lend a company money to set up a cattle ranch if the operation would
destroy too large a section of an endangered forest.
Finally, the unfortunate reality is that many habitats are not going to be
saved. To prevent the genetic legacy of those areas from being extinguished, as
many species as possible should be preserved in zoos, botanical gardens and
other "gene banks." There, scientists can study a small percentage of
threatened organisms and have the options of later returning them to the wild
or transplanting some of their genes into other species.
But the best place to preserve the earth's biodiversity is in the
ecosystems that gave rise to it. Man must abandon the belief that the natural
order is mere stuff to be managed and domesticated, and accept that humans,
like other creatures, depend on a web of life that must be disturbed as little
as possible.
COVERS GALLERY: Click here to see the cover image from 1988
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