The Fruitful Facets of Galton's Polyhedron 457
Goldschmidt called these pervasive changes "systemic mutations," and he
identified them as the underlying source of saltational events that produce new
species by transcending the ineffective Darwinian diversification of races:
For a long time I have been convinced that macroevolution must proceed
by a different genetic method ... A pattern change in the chromosomes,
completely independent of gene mutations, nay, even of the concept of the
gene, will furnish this new method of macroevolution... So-called gene
mutation and recombination within an interbreeding population may lead to
a kaleidoscopic diversification within the species, which may find
expression in the production of subspecific categories... The change from
species to species is not a change involving more and more additional
atomistic changes, but a complete change of the primary pattern or reaction
system into a new one, which afterwards may again produce intraspecific
variation by micromutation. One might call this different type of genetic
change a systemic mutation... Whatever genes or gene mutations might
be, they do not enter this picture at all. Only the arrangement of the serial
chemical constituents of the chromosome into a new, spatially different
order, i.e., a new chromosomal pattern, is involved (1940, pp. 205-206).This bold statement highlights the key issue surrounding Goldschmidt's role
in current reformulations of evolutionary theory. Goldschmidt clearly ties his
phenotypic concept of the "hopeful monster" to his genetic hypothesis of "systemic
mutation" as a cause. If these two notions are indissolubly linked, and if the
hopeful monster can only be conceived as a phenotypic manifestation of this
deeply fallacious genetic theory, then we may dismiss this colorful term as a
historical curiosity. I place Goldschmidt's denial of corpuscular genes, and his
attempt to construct a holistic genetics based upon position effects in a fully
integrated interchromosomal system, into the interesting category of major ideas
that we may honor as "gloriously wrong." Goldschmidt made a grand, not a paltry,
error—for his system proposes an entirely different way of knowing, with
intellectual and scientific ramifications at broadest scale. But this generous breadth
of vision doesn't make Goldschmidt's genetic system any less wrong, and the
obvious argument remains: If hopeful monsters and systemic mutations only
represent two aspects of the same phenomenon, then we must place the unitary
concept aside, however gently and with sympathetic interest.
But even a cursory investigation of Goldschmidt's career, and a first-pass
analysis of his writings, reveals a separate, older and more important theme behind
the concept of the hopeful monster. Goldschmidt sets most of his
macroevolutionary discussions in the context of developmental systems and their
ontogenies, not of idiosyncratic genetics and their operation. The confusions and
conflations within The Material Basis of Evolution remain both palpable and
frustrating—and must be regarded as Goldschmidt's own doing (and undoing). In
this book, he sometimes speaks of systemic mutations as