the extra 2 billion humans expected by 2020, which some esti-
mate will require 40 percent more food than produced today,
and that current productivity trends are not optimistic in
meeting these goals. Then the argument postulates that bio-
technology, which includes genetic modification as well as
other tools, should be one among many technologies available
for reaching this goal.
There is a logic to this argument. Between 1950 and 2000 the
world population rose from 2.5 to 6 billion people, yet the only
famines that occurred were largely due to political causes, like
the central planning failures in China and the dictatorship in
North Korea. Those not living under repressive regimes were
mostly able to eat, thanks in part to the Green Revolution. This
was not a political revolution but one of agricultural science,
where new plant breeding and chemical fertilizer techniques
allowed food production to increase faster than the world pop-
ulation. Technology saved the day, it seems. Will GMOs be the
technology that saves us in the coming decades?
Are GM crops more productive? There is no reason to
believe farmers using GM crops should have higher yields,
as the farmers who first adopt GM crops are different types
of farmers than those who do not, and their yields are influ-
enced both by the productivity of GM grains as well as their
land and managerial skills. These nuances are observed in
the United States where insect-resistant corn has increased
yields whereas herbicide-resistant soybeans have reduced
yields (though only slightly).
Only controlled experiments can isolate the effect of
genetic modification on yield, and some of these stud-
ies find that GMOs increase yields while others identify a
decline in yield. Yield is important but it is not everything.
A lower-yielding GM variety may still be preferred if it
reduces pesticide costs, is more resistant to drought, or helps
control pests for a different crop planted subsequently (e.g.,
planting GM canola this year to help control weeds in next
year's non-GM wheat).