464 THE STRUCTURE OF EVOLUTIONARY THEORY
phenotypes: "Translated into phylogenetic language, this would mean that
immense evolutionary effects could be brought about by changing the differential
growth rates of the whole body or organ at an early point in development, with all
the necessary secondary effects of such a change" (p. 545). In rare cases, such
ontogenetic cascades will produce a viable organism (by working within
developmental channels) lucky enough to find a favorable environment—in other
words, a hopeful monster: "We certainly know of many cases of mutational shifts
of the rate of certain developmental processes leading to non-viable results, for
example, caterpillars with pupal antennae, larvae of beetles with wings... But I
cannot see any objection to the belief that occasionally, though extremely rarely,
such a mutation may act on one of the few open avenues of differentiation and
actually start a new evolutionary line" (p. 544).
My pleasure in locating this resolution (in a 1933 article) for the textual
difficulties in Goldschmidt's 1940 book then became enhanced when I noted
another theme, by no means absent from the later book, but stressed in 1933 to a
far greater extent, and with clearer purpose. I have repeatedly emphasized, as the
central notion of this chapter, that the full formalist (or internalist) critique of
Darwinian functionalism embraces two themes, both illustrated by Galton's
incisive metaphor of the herkyjerky polyhedron—facet flipping (saltationism) and
channeling (constraint in the positive sense of preferred directions for change).
One might expect that the chief apostate and whipping boy of orthodoxy
would embrace the full range of a coherent opposing philosophy. We usually view
Goldschmidt as a pure saltationist, and the vehemence of orthodox reaction to only
half a loaf might seem puzzling. But in the 1933 article, Goldschmidt gives equal
weight to both internalist arguments—as he repeatedly, and explicitly, ties the
theme of channeling to its strongest version of orthogenesis. Saltation and
channeling march in tandem throughout his argument, and the entirety builds a
satisfying version of the full formalist critique.
I have already cited one Goldschmidtian invocation of orthogenesis linked to
saltationism, from the concluding paragraph: "I tried to show that a directed
orthogenetic evolution is a necessary consequence of the embryonic system which
allows only certain avenues for transformation" (p. 547). But the two themes
remain indissolubly connected throughout the article, and channeling receives as
much attention as saltation—whereas Goldschmidt did emphasize saltation and
downplay channeling in his later writings. In fact, in the 1933 article, Goldschmidt
invokes channeling at the very beginning of his macroevolutionary discussion, just
after citing the importance of development and even before he introduces the
argument for saltation:
A considerable number of developmental processes between egg and adult
have to be changed, in order to lead to a different organization.
Development, however, within a species is, we know, considerably one
tracked. The individual developmental processes are so carefully
interwoven and arranged so orderly in time and space that the typical result
is