By Henry I. Miller
Tuesday, July 21, 2015
It’s not unusual for a person with expertise in one
discipline to get into trouble when he expresses opinions in another. An
example is William Shockley, a Nobel laureate in physics for his research on
semiconductors, blundering into advocacy for racial eugenics. The phenomenon
recurred recently when financiers Mark Spitznagel and Nassim Taleb (author of
The Black Swan), neither of whom possesses the most rudimentary understanding
of the history or techniques of genetic modification, warned about the dangers
of genetic engineering in a bizarre commentary in the New York Times. They went
so far as to posit the possibility that modern molecular genetic engineering
could cause “complex chains of unpredictable changes in the ecosystem” that
could lead to worldwide catastrophe.
It’s true that as complexity increases, so does
uncertainty and the possibility of calamity. Arguably, it was the synergistic
failure of complex systems that gave rise to the great Northeast blackout of
2003, in which 50 million people lost power; and even to the First World War,
which, because of the complex web of alliances and treaties, the assassination
of a relatively obscure Austrian nobleman was able to trigger.
What Spitznagel and Taleb fail to appreciate is that the
molecular techniques of genetic engineering that they think are so dangerous
decrease the complexity of modern agriculture and the probability of unforeseen
outcomes.
According to Spitznagel and Taleb:
We are told that a modified tomato is not different from a naturally occurring tomato. That is wrong: The statistical mechanism by which a tomato was built by nature is bottom-up, by tinkering in small steps (as with the restaurant business, distinct from contagion-prone banks). In nature, errors stay confined and, critically, isolated.
What is wrong is their reasoning. A “modified tomato” is,
as they maintain, different from a “natural occurring tomato,” but not in the
ways they think.
Spitznagel and Taleb obviously have no clue about the
pedigree of “naturally occurring tomatoes.” Genetic modification by means of
selection and hybridization has been with us for millennia, and the techniques
employed along the way are part of a seamless continuum. Breeders routinely use
radiation or chemical mutagens on seeds to scramble a plant’s DNA to generate
new traits, and more than a half-century of “wide cross” hybridizations, which
involve the movement of large numbers of genes from one species or one genus to
another, have given rise to plants that do not exist in nature; they include
the varieties of corn, oats, pumpkin, wheat, rice, tomatoes, and potatoes that
we buy routinely.
In fact, with the exception of wild berries, wild game,
wild mushrooms, and most fish and shellfish, everything in American diets is
derived from organisms that have been genetically improved in some way. Even
today’s “heirloom” tomatoes, which predate the pest- and disease-resistant
hybrids most often grown commercially, are a far cry from their South American
forbears — small, hard, toxic fruit closer in appearance to a golf ball than to
a food. All of the tomatoes that we consume have been modified to be different
from their “natural” ancestors.
Grains have a similar story. They have been intensively
engineered over millennia for higher yields, pest and disease resistance, and
various desirable characteristics, yielding durum wheat for pasta, for example,
and so-called common wheat for bread. Although wheat varieties cultivated now
vary widely in their traits and genetics, all are derived from a common
precursor first domesticated in Turkey around 9000 b.c. and later genetically
improved by farmers, plant breeders, and biologists.
Animals, too, have been genetically engineered, mostly by
laborious and imprecise trial-and-error breeding techniques. For example, the
dozens of varieties of cattle raised today are all derived from the now-extinct
auroch, which was used both for food and as a beast of burden from ancient times
until the 17th century. A relatively recent (20th century) new food animal, the
“beefalo,” a cow–bison (buffalo) hybrid, combines the superior hardiness,
foraging ability, calving ease, and low-fat meat of the bison with the
fertility, milking ability, and ease of handling of the cow.
And wonder of wonders — not only has there not been an
apocalypse from all this genetic modification, but it has markedly increased
food security and humans’ longevity. (Recall the past century’s Green
Revolution!)
So what’s new? Not the genetic engineering of food, but
only the techniques for accomplishing it. And the newest methods —
recombinant-DNA technology, or “gene-splicing,” and the new gene-editing
techniques — are far more precise and predictable than their predecessors.
They’re an extension, or refinement, of more-primitive techniques.
Here’s the take-home lesson: Because the techniques of
molecular genetic engineering lead to greater control and certainty about the
result, their use decreases the complexity of food production and the
likelihood of what Spitznagel and Taleb call “unpredictable changes in the
ecosystem.”
It’s noteworthy that the imprecision of the earlier,
pre-molecular techniques led to several prominent mishaps, including the
introduction of a disastrous susceptibility of corn to mold (which in 1970
caused a significant reduction in the U.S. harvest), and new varieties of
potatoes, squash, and celery with (inadvertently) elevated levels of endogenous
toxins. These kinds of unforeseen problems are vastly less likely with the
newest techniques.
Because mishaps, significant or inconsequential, are far
less likely with the late-20th-century and 21st-century genetic-modification
techniques, Spitznagel and Taleb have gotten the logic exactly backwards. What
a sad commentary.
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