ISSUES
Feeding the five billion
New agricultural techniques can
keep hunger at bay Well-fed Luddites on a field trip
SHRIMPS are messy creatures. When scrubbed, shelled and served
with lime leaves and lemon grass in a hot Thai tom yam koong
soup, they taste wonderful. But while alive, they excrete
large amounts of toxic sludge.
On Thai shrimp farms, the traditional way of dealing with this
sludge is to toss it in the nearest river. Land used for
shrimp farming soon becomes polluted and unusable, so shrimp
farmers keep cutting down fresh forest to build new shrimp
pools. Since farmed shrimps live in their own waste, they
often fall sick. So farmers stuff them with antibiotics, which
could end up in your tom yam koong.
Fortunately, there is a technological fix. Bio Solutions, a
Thai firm, has developed a pill containing bacteria that eat
shrimp excrement. Throw the pill in the pool, and the bacteria
multiply until they run out of food. Then they obligingly
starve to death, in a tidy, biodegradable way. If Asia is
going to feed itself, says Charles Liu, the president of Bio
Solutions, agricultural biotechnology has to be part of the
answer. That is what you would expect him to say - but he has
a point.
Predictions that people would multiply beyond their capacity
to feed themselves, like those Thai bacteria, have repeatedly
been proved wrong. In 1798, Thomas Malthus foretold famine
just as farm yields were taking off. To his credit, he later
admitted that he was wrong. Not so Paul Ehrlich, an American
biologist who wrote in 1969: The battle to feed humanity is
over. In the 1970s hundreds of millions of people will starve
to death. They didn't.
The world's population grew much as expected, but food output
more than kept pace. During the 1960s and 70s, a green
revolution swept the developing world. Millions of farmers
started using higher-yielding hybrid seeds, chemical
fertilisers, pesticides and weed-killers. The results were
remarkable. For example, Mr Ehrlich had predicted that by the
mid-1970s, India would be so obviously beyond hope that
America would stop sending food aid. Yet by 1990, India was
exporting surplus grain. Chinese rice farmers, using similar
techniques, raised production by two-thirds between 1970 and
1995. By one estimate, the green revolution saved a billion
people from starvation.
There were some side-effects. Governments subsidised the new
chemicals,
which encouraged their over-use. This damaged the environment
in many
parts of the developing world. But the main worry about the
green revolution is that it has run out of steam. There are
still areas - mainly in Africa - where its techniques have yet
to be tried (see table 1, next page). But in most of the
developing world, the gains in productivity from it are
tailing off.
Globally, 800m people are still malnourished. Heavily
subsidised farmers in rich countries produce enough surplus
food to feed the hungry, but not at a price the hungry can
afford. Even if the rich world's surplus were simply given to
the poor, this would not solve the problem. Most poor people
earn their living from agriculture, so a deluge of free food
would destroy their livelihoods. The only answer to world
hunger is to improve the productivity of farmers in poor
countries.
This will be difficult. The developing world's population is
growing fast, but the amount of land available for cultivation
is not. To feed the 2 billion new mouths expected by 2025, new
ways must be found to squeeze more calories out of each
hectare. But then more people means not just more stomachs to
fill, but also more brains to figure out how to fill them.
There are plenty of good ideas available. The most powerful is
biotechnology, and especially genetic modification (GM). It is
a young science: biologists first found ways of manipulating
recombinant DNA in the early 1970s. The first commercially
available genetically modified organism (GMO) appeared a mere
five years ago. Supporters of GM expect it to end world
hunger. Opponents fear it may poison us all. It is worth
stepping back for a moment to consider the evidence.
For and against GMOs
Farmers have been manipulating genomes since long before they
knew about genes. For thousands of years, they sought to
transfer desirable traits from one plant species to another by
cross-breeding: this was how wild grasses were turned into
wheat. They also selectively bred animals to make them fatter
and tastier: this was how wild boars became pigs.
GM aims to achieve similar results, but faster. It typically
takes 8-12 years to produce a better plant by cross-breeding.
But if scientists can isolate a gene in one species that is
associated with, say, the ability to grow in salty soil, they
can sometimes transfer it directly into the genetic code of
another species, without spending years crossing successive
generations.
GM is more precise than cross-breeding, too. As any parent
knows, sexual reproduction is unpredictable. The union of a
brilliant woman and an athletic man does not always produce a
brilliant and athletic child. In plants, as in people, some
traits are inherited, others are not. At least in theory, GM
solves this problem by transferring only the gene associated
with the trait that the farmer wants.
The final advantage of GM is that it allows the transfer of
traits between unrelated species. You cannot cross-breed cacti
with corn, but you can take a cactus gene that promotes
drought resistance and put it in a corn plant.
So far, scientists have produced GM crops that are more
resistant to viruses and insects, and more tolerant of
herbicides. In the future, GM could fill the world's larders
with high-protein cereals, vegetables with extra vitamins, and
all manner of cheaper, tastier and more nutritious foods than
we currently enjoy. Researchers at Cornell University in
America have even created bananas that contain a vaccine for
hepatitis B. A single banana chip inoculates a child for
one-fifteenth of the price of an injection, and with fewer
tears.
Against these actual and potential benefits must be set the
potential dangers. Shifting genes between different species
could create health risks. For example, soyabeans given brazil
nut genes have been found to express brazil nut proteins of
the sort that might trigger allergic reactions. Soyabeans are
used in thousands of food products, so if the problem had not
been spotted this could have made life hazardous for people
with nut allergies.
GM crops may also cause environmental problems. Their pollen
might blow
into fields of ordinary crops and fertilise them. There is no
evidence that this has happened so far, but it is possible,
with unknown effects. Also, crops genetically modified to
repel pests might spur the evolution of super-pests or poison
other species. Laboratory tests have shown that butterfly
larvae are harmed when fed the pollen of plants genetically
modified to express a toxin called Bacillus thuringiensis
(Bt), which protects corn from corn borers and cotton from
boll worms.
All these risks are rather speculative. As with any new
technology, it is impossible ever to prove conclusively that
GM foods are safe. It is essential to test GM products
carefully before releasing them, and to keep monitoring them
afterwards. But so far, there is no evidence that GM crops
hurt either humans or the environment. Americans have been
munching modified corn and soyabeans for six years without
discernible harm. And so far it looks as though GM crops
actually help protect the environment, by reducing the need
for chemical pesticides.
Last year, about 44m hectares of transgenic crops were
planted, more than 20 times the area in 1996. Most of these
fields, however, were in North America. Developing countries
have yet to see much benefit from GM technology. But that
could change. Among poor countries, the most enthusiastic
adopter of GM technology has been China, where the government
frets about food security. In 1997-99, China gave 26
commercial approvals for GM crops, including transgenic
peppers, tomatoes, rice and cotton. The most commercially
successful of these has been Bt cotton.
Cotton-chomping boll worms have grown resistant to pesticides.
In 1992, these worms destroyed the entire cotton crop in some
parts of China, ruining large numbers of farmers and
bankrupting textile factories. So when Monsanto, a big
American biotech firm, started selling boll-worm-resistant Bt
cotton seeds, the Chinese government snapped them up. But
cotton now covers half a million hectares of Chinese soil.
Production costs have fallen by 14%, despite the hefty price
that Monsanto charges for its seeds. Chinese scientists are
now working on their own GMOs, and have already produced at
least four new versions of Bt cotton.
The Chinese example is hopeful, but not unambiguously so. One
reason that China's government was able to embrace GM
technology is that the country is a dictatorship. Dissident
voices are silenced or ignored. A few democracies, such as
America, Canada and Argentina, have taken to GM food. But in
Europe, although regulators say that GM products are safe, an
energetic campaign by non-governmental organisations (NGOs)
has convinced consumers that they are not, and dissuaded
supermarkets from stocking them. Through the Internet, the
campaign has spread to the developing world.
India, like China, has lots of poor rural folk who must
somehow be fed. Anything that raises rural incomes is likely
to help. Indian field trials found that Bt cotton produced 40%
more fibre than ordinary cotton, with five fewer chemical
sprays for each crop. For a typical small farmer with five
hectares, this would save $50 per season, a huge sum by local
standards. The farmer would also inhale less pesticide.
Despite these findings, the Indian government refuses to
permit the commercial planting of Bt cotton, largely because
of pressure from NGOs. Protesters have invaded field trials
and burned GM crops. Some even blocked the delivery of
American food aid to cyclone victims, arguing that it probably
contained GM products.
Some poor countries hesitate to plant GMOs for fear of
upsetting Europeans. NGOs claim that GM crops may contaminate
neighbouring fields with their pollen. It would be a short
step to call for a boycott of all the food exports, modified
and unmodified, of countries where GMOs are widely grown. Even
for developing countries that allow GM crops to be planted
only in isolated plots for research purposes, the risk of a
boycott remains. The peasants who live near research centres
often notice how good the new crops are and steal the seeds.
Unlike the techniques of the green revolution, GM technology
was largely developed by private companies. In the eyes of
many, this made it suspect, but such suspicion is largely
misplaced. The profit motive gives companies a strong
incentive not to poison their customers. But it gives them no
incentive to cater for people who cannot afford their
products. Better versions of poor people's staples, such as
millet, sorghum and cassava, will probably appear only if
governments pay for some of the research, but the current
hysteria about GMOs makes this politically difficult. When the
UNDP recently suggested that GM technology could help the
poor, it was met with howls of outrage.
The many ways of fighting hunger
GM is not the only weapon in the war on hunger. Democracy is
important too: famines usually occur only in dictatorships.
And other technologies too can produce impressive results:
using less controversial biotechnology, the UNDP and the
Japanese government recently produced a high-yielding hybrid
rice that grows faster and contains more protein than ordinary
varieties. But battles are easier to win if you have many
weapons at your disposal. To remove the most powerful one from
the arsenal seems unwise.
For the poor, GM appeared at an awkward time. After several
people in
Britain died of what was almost certainly a human version of
mad-cow disease, Europeans lost faith in their governments'
ability to keep dangerous food off their plates. Since people
in rich countries rarely go hungry, they were not wildly
excited about the promise of cheap and abundant food. Perhaps
they will change their minds when scientists create better
rather than simply cheaper foods: cholesterol-free bacon,
perhaps.
But in the meantime, it is sad
that the priorities of the well-fed few should make it harder
for the world's hungry billions to feed themselves.
Courtesy
The Economist November 10, 2001
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