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The Final Countdown
Text by Boyce Rensberger
Thousands of species around the globe are becoming extinct,
but E. O.Wilson, the man who made biodiversity a household word, says all
is not lost-yet.
If, a century from now, earthlings gaze upon their planet and wonder
at its extraordinary diversity of life, they are likely to hold in reverence
the name of one man: Edward O. Wilson. Indeed, many today who fear the
rapid destruction of biological diversity already regard Wilson as the
nearest thing to a savior that science has produced.
Earth's biodiversity has not been saved-not yet. Uncounted species
are endangered, flickering out of existence in large numbers before they
can even be named. But the man who has done more than almost anyone else
to focus society's attention on the value of biological diversity, and
the threats to it, says there is reason for hope. Though he would be the
last to say so, Wilson's campaign on behalf of the living world has helped
make the conservation movement's goals attainable.
No starry-eyed radical, the Harvard University zoologist helped
establish the concept of biological diversity, or biodiversity for short,
as a measure of an ecosystem's value to the planet.
The more species of plants, animals, and other life-forms in a given
region, the more resistant that region is to destruction and the better
it can perform its environmental roles of cleansing water, enriching the
soil, maintaining stable climates, even generating the oxygen we breathe.
In 1963 Wilson, along with Robert H. MacArthur, developed the theory called
"island biogeography": As the size of a natural area shrinks, the number
of species it can sustain shrinks faster. Since then the theory has been
confirmed with alarming repetition.
Now 70 and supposedly retired, Wilson is as busy as ever. He continues
studying his specialty, ants; he's working on a new classification of one
major ant group. He still writes eloquent books; 2 of his 20 titles, On
Human Nature and The Ants, have won Pulitzer Prizes. He still
helps guide environmental organizations; currently, he's on the boards
of the Nature Conservancy, Conservation International, and the American
Museum of Natural History. And he still lectures around the world to save
all living species; his Alabama-bred folksiness, combined with a sterling
scientific reputation, makes him highly persuasive.
I've followed Wilson's career since 1975, when I wrote about his
controversial book Sociobiology for The New York Times. In
those days, he was often attacked for suggesting in that book that certain
human behaviors are influenced by urges or instincts that evolved through
natural selection. The attacks hurt him deeply. Today sociobiology is widely
accepted and, because of his work in biodiversity, Wilson is lionized by
many who attacked him decades earlier. "I haven't changed," he observes
quietly.
We spoke in his cluttered office at Harvard's Museum of Comparative
Zoology, surrounded by stacks of papers, shelves of books, and oversize
models of his beloved ants.
Q: As you've helped teach us, we're losing biodiversity at
a rate that compares with the great mass extinctions of the prehistoric
past. If nothing is done over the next century, how is the earth going
to be different?
A: If we continue at the current rate of deforestation and destruction
of major ecosystems like rainforests and coral reefs, where most of the
biodiversity is concentrated, we will surely lose more than half of all
the species of plants and animals on earth by the end of the 21st century.
Q: Is that loss going to happen in isolated patches, or will
it be worldwide?
A: Most of the destruction will be from what we today recognize
as the "hot spots," where there already is lots of diversity and where
habitats are being destroyed. These are primarily but not entirely in the
tropics.
Q: A hundred years from now, will America look much different?
A: In the United States the trajectory is less threatening,
but even here we would see a shrinkage of fauna and flora over most of
the country. And especially in our own hot spots, such as Hawaii and California.
For example, in Hawaii alone, where species are disappearing at one of
the highest rates in the world, there are more than 100 species of trees
that consist of 20 individuals or fewer. So in a century, America would
still be biologically rich in most places. But without a stronger conservation
policy, it would be partly impoverished, and especially locally a lot of
individual states would lose species.
The natural-heritage program of the Nature Conservancy estimates
that about 1 percent of native American species of plants and animals have
become extinct already, and another 30 percent are in some degree of vulnerability.
Even in our national parks, a substantial percentage of mammals have gone
extinct-even though they're protected-because the parks are too small.
Q: How will the loss of biodiversity affect human life?
A: On a global basis, I have no doubt at all that there would
be severe effects on the quality of life-support systems such as watersheds
and air quality and rainfall.
For example, in the Amazon rainforest, a large part of the rain
that falls comes from evaporation from the forest itself. As the forest
is removed, then a major source of rain is also removed, and substantial
parts of the whole Amazon basin could be turned into permanent grassland,
with effects radiating out into the breadbasket states of southern Brazil.
They would be prone to drought if the Amazon basin dried out.
Q: What has made you so personally interested in this issue?
A: I was a naturalist virtually from childhood, from the age
of about nine, when I went out exploring the woods and the fields where
we lived. Growing up, especially in Alabama, I would go off on my own,
exploring nature because it gave me so much pleasure. I did this right
up through my college years-at the University of Alabama and Harvard. The
same thing happened later, when I began doing research in the tropics.
Especially in the tropics, I became aware of how little of the natural
environment has survived.
And so, since my main interest has always been biodiversity,
I've been keenly aware that a large part of it was going down the drain.
At times, it's made me feel alarmed or depressed.
Q: When did you first become alarmed?
A: In the 1950s, when I was a graduate student and going out
to do field research in the tropics. I saw the destruction even then. But
I didn't become active in the global environment movement until the late
'70s. Up to that time I thought that scientists could pretty well stand
aside and let the conservation organizations take care of the activism
and building of reserves and restoration of lost habitats. But then I came
to realize-especially when others in my field were becoming active in conservation,
such as Tom Lovejoy, who is now at the World Bank, and Peter Raven, director
of the Missouri Botanical Garden-that scientists had to cross over and
get involved because the biodiversity was just disappearing too fast. Conservation
organizations did not have the scientific know-how they needed to do planning
on a systematic and global scale. That's when I got active.
Q: So did the activist groups change for the better as a
result?
A: Yes, but I wasn't solely responsible. I did help change the
policy of the World Wildlife Fund-U.S. when I became a member of the board
of directors. In the early '80s the World Wildlife Fund changed from an
emphasis on specific charismatic species-the giant panda, the leopard,
whatever it was-as targets for conservation to biodiversity as a whole.
The goal became to save the ecosystem. The effect would be not just to
protect the charismatic species but all the rest of the habitat that they
need to live. Another shift occurring at that time was also very important.
The economic and social welfare of the people who live around the protected
areas began to be taken into full account. An environmental program today
involves what saving the environment can do for the people, how it can
be fitted into the local economy and given value that people immediately
understand.
Q: This brings up the question of what individuals can do.
Do you think individuals can make choices that matter in the big picture?
A: That's something everybody should do. I would not eat swordfish,
for example. It's one of the species driven to commercial rarity. But more
important, I think we should be more alert about not buying or using products
from species that are protected by cites [the Convention on International
Trade in Endangered Species]. Also, there are a lot of personal habits
that, if moderated only in this country, could contribute significantly
to saving endangered species.
Q: Like what?
A: Eating imported beef. Before we realized what was happening,
the importation of beef from Costa Rica was a significant factor in removing
most of its rainforest. Costa Rica has been essentially stripped of its
forest in the past 50 years.
Another good example is coffee-shade-grown versus open-field.
Shade-grown coffee is planted among the trees of the natural forest and
not in cleared fields. Most aficionados agree that it tastes better. I
don't drink coffee, so I'm just quoting. When people ask for shade-grown
coffee, they're protecting the forests of Latin America, where a large
part of the biodiversity continues to be preserved. If you leave enough
of the canopy of the forest and enough of the leaf litter, it's not the
same as the original rainforest, but it still has a lot of the biodiversity
in it.
Q: Do you think the public has grasped the value of whole
ecosystems?
A: Apparently only a minority understand this. The last survey
that I know of shows that roughly 20 percent of Americans understand what
biodiversity is.
Q: Still, you've said you have hope?
A: I believe that the fate of the world's flora and fauna depends
on a combination of science, education, and ethics. We have to get a much
better scientific understanding of where biodiversity is and what's happening
to it and its value for humanity. And we have to get an understanding of
biodiversity into the mainstream of public consciousness so it becomes
a principal factor in economic and social policy.
Will this happen? I believe it can, and it must happen soon.
The world environment is changing so fast that there is a window of opportunity
that will close in as little time as the next two or three decades. I've
always thought that we would lose a lot of biodiversity, but how much is
hard to say. It could be something like 10 percent of species. But that
is far better than the 50 percent or more we will certainly lose if we
let things continue as they are today.
Hot Spots
1. Mesoamerican forests 2. Caribbean 3. Tropical Andes 4. Ecuador 5.
Amazonian forest 6. Atlantic forest 7. Guinean forest 8. Cape Floristic
Province 9. Mediterranean 10. Madagascar/Indian Ocean islands 11. Western
India/Sri Lanka 12. Eastern Himalayas 13. Indonesia/Malaysia 14. Philippines
15. Southwestern Australia 16. Wallacea/Tasmania 17. New Caledonia 18.
Polynesia/Micronesia Biodiversity is not spread evenly across the planet.
Some areas, particularly in the tropics, harbor far greater concentrations
of species than average. In fact, more than half the earth's species are
found in "hot spots" covering only 2 percent of land. These areas also
claim two-thirds to three-quarters of the world's most endangered plants
and animals. In the Amazonian forests of Brazil, for example, 54 percent
of the trees, 80 percent of the primates, and more than half of the other
mammals live nowhere else. Source: Conservation International
Extinctions in the United States
Scientists estimate that the current extinction rate is approaching
1,000 times the background rate-the rate since the last major extinction,
65 million years ago. If trends continue, this may climb to 10,000 times
in the next century. The graph shows cumulative extinctions, broken down
by animal groups. Source: Council on Environmental Quality (The data after
1986 are estimates based on current trends.)

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