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The geneticist Antoine Danchin once used the parable of the Delphic boat
to describe the process by which individual genes could produce the observed
complexity of the natural world. In the proverbial story, the oracle at Delphi is
asked to consider a boat on a river whose planks have begun to rot. As the
wood decays, each plank is replaced, one by one—and after a decade, no plank
is left from the original boat. Yet, the owner is convinced that it is the same
boat. How can the boat be the same boat—the riddle runs—if every physical
element of the original has been replaced?
The answer is that the “boat” is not made of planks but of the relationship
between planks. If you hammer a hundred strips of wood atop each other, you
get a wall; if you nail them side to side, you get a deck; only a particular
configuration of planks, held together in particular relationship, in a
particular order, makes a boat.
Genes operate in the same manner. Individual genes specify individual
functions, but the relationship among genes allows physiology. The genome is
inert without these relationships. That humans and worms have about the
same number of genes—around twenty thousand—and yet the fact that only
one of these two organisms is capable of painting the ceiling of the Sistine
Chapel suggests that the number of genes is largely unimportant to the
physiological complexity of the organism. “It is not what you have,” as a
certain Brazilian samba instructor once told me, “it is what you do with it.
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