Darwin's Dangerous Idea - Evolution and the Meaning of Life

220 BIOLOGY IS ENGINEERING Stuart Kauffman as Meta-Engineer 221
D'Arcy Thompson (1917) famously said that everything is what it is
because it got that way, and his own reflections on the historical processes of
development led to his promulgation of "laws of form" that are often cited as
examples of biological laws that are irreducible to physical laws. The
importance of such reconstructions of developmental processes and the
investigation of their implications is undeniable, but this issue is sometimes
misplaced in discussions that attempt to contrast such developmental
constraints with functional analyses. No sound functional analysis is complete
until it has confirmed ( as much as these points ever can be confirmed )
that a building path has been specified. If some biologists have habitually
overlooked this requirement, they are making the same mistake as the art
historians who ignore the building process of their monuments. Far from
being too taken with an engineering mentality, they have not taken engineering
questions seriously enough.
7. STUART KAUFFMAN AS META-ENGINEER
Since Darwin, we have come to think of organisms as tinkered-together
contraptions and selection as the sole source of order. Yet Darwin could
not have begun to suspect the power of self-organization. We must seek
our principles of adaptation in complex systems anew.
—STUART KAUFFMAN, quoted in Ruthen 1993, p.
138
History tends to repeat itself. Today we all recognize that the rediscovery
of Mendel's laws, and with them the concept of the gene as a unit of heredity,
was the salvation of Darwinian thinking, but that was not how it appeared at
the time. As Maynard Smith notes (1982, p. 3), "The first impact of
Mendelism on evolutionary biology was distinctly odd. The early Mendelians
saw themselves as anti-Darwinians." This was just one of many selfstyled
anti-Darwinian revolutions that have turned out to be pro-Darwinian
reformations, dragging Darwin's dangerous idea from one sickbed or another
and putting it back to work. Another that is unfolding before our eyes today is
the new direction in evolutionary thinking spearheaded by Stuart Kauffman
and his colleagues at the Santa Fe Institute. Like every good bandwagon, it has
a slogan: "Evolution on the Edge of Chaos." Kauffman's new book, The
Origins of Order: Self-Organization and Selection in Evolution (1993),
summarizes and extends the research he has been engaged in for several
decades, and lets us see for the first time how he himself places his ideas in
the context of the history of the field.
Many have heralded him as a Darwin-slayer, finally driving that oppressive
presence from the scene, and doing it, moreover, with the flashing blade of
brand-new science: chaos theory and complexity theory, strange attractors
and fractals. He himself has been tempted by that view in the past (Lewin
1992, pp. 40-43), but his book bristles with warnings, fending off the
embrace of the anti-Darwinians. He begins the preface of his book (p. vii) by
describing it as "an attempt to include Darwinism in a broader context":
Yet our task is not only to explore the sources of order which may lie
available to evolution. We must also integrate such knowledge with the
basic insight offered by Darwin. Natural selection, whatever our doubt in
detailed cases, is surely a preeminent force in evolution. Therefore, to
combine the themes of self-organization and selection, we must expand
evolutionary theory so that it stands on a broader foundation and then
raise a new edifice. [Kauffman 1993, p. xiv.]
I go to such lengths to quote Kauffman himself on this point since I have
also felt the strong wind of anti-Darwinian sentiment among my own readers
and critics, and know that they will be strongly motivated to suspect that I am
merely reworking Kauffman's ideas to fit my own biased view! No, he
himself—for whatever that is worth—now sees his work as a deepening of
Darwinism, not an overthrow. But, then, what can be his point about "spontaneous
self-organization" as a source of "order" if not a flat denial that
selection is the ultimate source of order?
Now that it is possible to build truly complex evolutionary scenarios on
computers, rewinding the tape over and over, we can see patterns that eluded
earlier Darwinian theorists. What we see, Kauffman claims, is that order
"shines through" in spite of selection, not because of it. Instead of witnessing
the gradual accrual of organization under the steady pressure of cumulative
selection, we witness the inability of selective pressure (which can be
carefully manipulated and monitored in the simulations) to overcome an
inherent tendency of the populations in question to resolve themselves into
ordered patterns. So this seems at first to be a striking demonstration that
natural selection cannot be the source of organization and order after all—
which would indeed be the downfall of the Darwinian idea.
But there is another way of looking at it, as we have seen. What conditions
have to be in effect for evolution by natural selection to occur? The words 1
put into Darwin's mouth were simple: Give me Order, and time, and I will
give you Design. But what we have subsequently learned is that not every
variety of Order is sufficient for evolvability. As we saw illustrated by Conway's
Game of Life, you have to have just the right sort of Order, with just
the right mix of freedom and constraint, growth and decay, rigidity and
fluidity, for good things to happen at all. You only get evolution, as the Santa
Fe motto proclaims, on the edge of chaos, in the regions of possible law that