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Biographical Sketch
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Richard Goldschmidt |
Richard Goldschmidt (1878-1958), a brilliant but unorthodox
geneticist, did not believe that Charles Darwin's idea of slow, gradual changes
could account for the origin of species. Forced out of his native Germany by
the Nazis, he continued to develop his research at the University of California
at Berkeley, where he wrote his magnum opus The Material Basis of
Evolution published in 1940.
Although he recognized the constant accumulation of small
changes in populations (microevolution), he believed they did not lead to
speciation. Between true species he saw "bridgeless gaps" that could only be
accounted for by large sudden jumps, resulting in
"hopeful monsters."
Goldschmidt tried to explore possible genetic mechanisms of
how rapid change might occur in lineages of organisms. He suggested that a
relatively small change might have a large effect on the phenotype, especially
through "controlling" genes which mediate the expression of the organism's
blueprint. Later, he thought macromutations or mutants (which used to be called
"monsters") might arise in a single generation, and this biological novelty
might enjoy a selective advantage under changing environmental conditions.
That was where the "hopeful" came in. One hope was that the
mutation would prove so useful in the newly changed environment that it would
become selected as a new norm. Another hope was that the variant would appear
often enough in the population to allow several similar "monsters" to find one
another and produce offspring. There is a grotesque humor about the unfortunate
phrase "hopeful monsters" that lent itself to caricatures of Goldschmidt's
ideas and obscured the theoretical issues.
[ Richard Milner,
The
Encyclopedia of Evolution, NY: Facts on File, 1990, pp. 221-222. ]
Gould on Richard Goldschmidt
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"As a Darwinian, I wish to defend Goldschmidt's postulate that
macroevolution is not simply microevolution extrapolated,
and that major structural transitions can occur rapidly without a smooth series of
intermediate stages. . . . In his infamous book of 1940, Goldschmidt specifically
invokes rate genes as a potential maker of hopeful monsters: 'This basis is
furnished by the existence of mutants producing monstrosities of the required type
and the knowledge of embryonic determination, which permits a small rate change in
early embryonic processes to produce a large effect embodying considerable parts
of the organism.' In my own, strongly biased opinion, the problem of reconciling
evident discontinuity in macroevolution with Darwinism is largely solved by the
observation that small changes early in embryology accumulate through growth to
yield profound differences among adults."
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"The Return of
Hopeful Monsters" Natural History magazine 86 (June 1977): 24, 30.
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"By proposing a comprehensive formalist theory in the heyday
of developing Darwinian orthodoxy, Richard Goldschmidt became the whipping boy of
the Modern Synthesis—and for entirely understandable reasons. Goldschmidt
showed his grasp, and his keen ability to utilize, microevolutionary theory by
supporting this approach and philosophy in his work on variation and intraspecific
evolution within the gypsy moth, Lymantria dispar. But he then expressed
his apostasy by advocating discontinuity of causality, and proposing a largely
nonselectionist and formalist account for macroevolution from the origin of
species to higher levels of phyletic pattern. Goldschmidt integrated both themes
of saltation (in his concept of "systemic mutation" based on his increasingly
lonely, and ultimately indefensible, battle to deny the corpuscular gene) and
channeling (in his more famous, if ridiculed, idea of "hopeful monsters," or
macromutants channeled along viable lines set by internal pathways of ontogeny,
sexual differences, etc.). The developmental theme of the "hopeful monster"
(despite its inappropriate name, virtually guaranteed to inspire ridicule and
opposition), based on the important concept of "rate genes," came first in
Goldschmidt's thought, and always occupied more of his attention and research.
Unfortunately, he bound this interesting challenge from development, a partially
valid concept that could have been incorporated into a Darwinian framework as an
auxiliary hypothesis (and now has been accepted, to a large extent, if under
different names), to his truly oppositional and ultimately incorrect theory of
systemic mutation, therefore winning anathema for his entire system. Goldschmidt
may have acted as the architect of his own undoing, but much of his work should
evoke sympathetic attention today."
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The
Structure of Evolutionary Theory. Cambridge, MA: Harvard Univ.
Press, 2002, p. 68.
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