The Modern Synthesis as a Limited Consensus 547
during the 1940's and 1950's (in time for the Darwinian centennial of 1959); but
the refinement of adaptationist arguments to nearly exclusive operation at the
organismic level followed later. This reform* emerged largely within the field of
animal behavior, where the ethological tradition, particularly in the work of
Konrad Lorenz, had long promulgated a loose and largely unconsidered approach
to multilevel selection.
The primary impetus to explicit debate appeared with the publication, in
1962, of V. C. Wynne-Edwards's Animal Dispersion in Relation to Social
Behavior. Since most evolutionists now regard Wynne-Edwards's primary
argument as wrong (and I do not dispute this consensus), we greatly undervalue his
work and misconstrue its importance. Most evolutionists today, many of who have
never read Wynne-Edwards, know his book only by reputation as a dumb
argument for group selection that George Williams and others thoroughly
demolished. I regard this assessment as entirely unfair. Wynne-Edwards's claim for
group selection may be wrong, but I can cite few other theories, presented within
evolutionary biology during my career, that could be deemed so challenging in
implication, so comprehensive in claims, so fascinating in extension, and so
thought-provoking.
First of all, and essential for grasping the book's sweep, "Animal Dispersion"
presents a theory about organic self-regulation of population numbers, not
primarily an argument for group selection in general (although group selection
serves as a fundamental feature of the proposed mechanism). Wynne-Edwards
begins, as so many others have done (including Darwin), with an analogy to human
institutions. When predators show no restraint in the midst of plenty, ecosystems
may crumble as both predators and prey succumb. He speaks with feeling about
the collapse of Arctic whaling (1962, p. 5): "The stocks of the two right whales
have never recovered, and the population of Greenland-whaling men and of those
who ministered to them has become effectively extinct."
Wynne-Edwards then generalizes from carnivory to food-based limitation in
any kind of eating, and to the transcendent need for regulating population sizes of
consumers in any ecosystem. I am fascinated that Wynne-Edwards, in this
statement, invokes the same, largely metaphysical, argument that Darwin proposed
in specifying a summum bonum for the construction of nature (a situation
established by very different mechanisms in Wynne-Edwards's and Darwin's
systems): the old principle of plenitude, or maximization of the kinds and numbers
of organisms in any given segment of earthly real estate (see p. 229 for Darwin's
version):
*Although I strongly advocate a hierarchical model of multilevel selection (see
Chapters 8 and 9), I regard this restriction to organismic selection as an important and
positive reform. Earlier claims for group and higher-level selection had been formulated
so vaguely and falsely that they impeded our understanding of both this important
concept and of the theory of selection in general. This salutary reform tore down
erroneous standards and insisted that no further claims be made until the logical edifice
could be properly rebuilt—no examples without a proper substructure; no paintings
without a strong frame.