The Fruitful Facets of Galton's Polyhedron 461
both eyes on one side of the head is only a monster; a benthic flatfish with both
eyes on the head's upper surface, with better scanning of surroundings as a lucky
result, becomes a hopeful monster. A short and bow-legged dog is merely a
monster; a frankfurter that can drag badgers from their holes is a hopeful monster.
(2) More importantly, hopeful monsters must pass a developmental criterion.
The vast majority of mutations with large phenotypic effects are lethal—that is,
just monsters. However, certain rare mutations will produce extensive, but viable,
phenotypic changes because they operate within the confines of a well regulated
developmental system. Such changes yield workable organisms (which may thrive
if they become lucky enough to find a welcoming environment), rather than
inviable hodge-podges of unintegrated systems in varying phases of ontogeny. The
fecund macroevolutionary monster becomes potentially "hopeful" when all
phenotypic effects unfold in a coordinated manner within a regulated
developmental system. In his autobiographical statement, just before admitting that
he had originated the term "hopeful monster" in partial jest, Goldschmidt linked his
concept firmly to the developmental theme: "What addition to Darwinism was
needed in order to account for the macroevolutionary processes? The solution was
the existence of macromutations, which, in rare cases, could affect early embryonic
processes so that through the features of embryonic regulation and integration at
once a major step in evolution could be accomplished and fixed under certain
conditions" (1960, p. 318).
Invoking the classical formalist theme of constraints and channels,
Goldschmidt argues that a knowledge of developmental systems and their norms of
reaction can specify the range of perturbations that might yield hopeful monsters—
a clear invocation of "developmental constraint" in its positive mode of enabling
(see Chapter 10): "Within a constant genotype the potentialities of individual
development may include a range of variation of the same phenotypic order of
magnitude which otherwise characterizes large evolutionary steps based upon
changes in the genotype. The norm of reaction thus shows that paths are available
for changes in the genotype (mutations in the broadest sense) without upsetting
normal developmental processes" (p. 260).
Goldschmidt designates this creative constraining force in the last phrase—
"without upsetting normal developmental processes." If shifts to alternate
pathways discombobulate development, then any resulting monster must be
hopeless. Many intricately complex systems simply fall apart or change in
injurious ways under the impact of major perturbations. But the regulation of
organic systems has evolved to accommodate impacts and to integrate changes into
canalized and viable pathways. Goldschmidt's famous phrase transcends whimsy
or nonsense—once we grasp the intended developmental theme. Goldschmidt
granted hope to his monsters because regulation can integrate certain large
alterations of phenotype into viable systems of development.
- The origin and subsequent ontogeny of hopeful monsters (both the term
and the concept) reveal a "smoking gun" for centrality of the developmental