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Biographical Sketch
J. B. S. Haldane was one of the great rascals of
science—independent, nasty, brilliant, funny and totally one of a kind.
Son of an Oxford professor of physiology, he began in science as his father's
assistant. Eventually he taught genetics and biometry at University College,
London, where he helped create the modern Synthetic Theory of evolution.
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J. B. S. Haldane | |
He learned
Mendelian genetics while still a boy by
breeding guinea pigs and often served as one himself when he helped his
father. In one childhood episode, the elder Haldane made him recite a long
Shakespearean speech in the depths of a mine shaft to demonstrate the effects
of rising gases. When the gasping boy finally fell to the floor, he found he
could breathe the air there, a lesson that served him well in the trenches of
World War I.
A physically courageous 200-pounder, Haldane continued the
family tradition of using his own body for dangerous tests. In one experiment,
he drank quantities of hydrochloric acid to observe its effects on muscle
action; another time he exercised to exhaustion while measuring carbon
dioxide pressures in his lungs.
Haldane was immensely cultivated; he had mastered Latin,
Greek, French and German while still a student. Later, he wrote extensively
on history and politics, and made important research contributions to
chemistry, biology, mathematics and genetics. He is best remembered (along
with E. B. Ford and R. A. Fisher) as an innovative pioneer in population
genetics. Haldane's brilliance helped define the field, which reshaped modern
evolutionary biology.
During World War I, Haldane volunteered for the Scottish
Black Watch and was sent to the front. There he found, to his shock and
dismay, that he liked killing the enemy. Twice wounded, he personally
delivered bombs and engaged in sabotage behind enemy lines, prompting his
commander to call him "the bravest and dirtiest officer in my Army."
In 1924, Haldane published a remarkable work of fiction,
Dædalus.
It was the first book about the scientific feasibility of "test-tube babies,"
brought to life without sexual intercourse or pregnancy. At the time, it was
regarded as shocking science fiction. Haldane wrote it as a student might a
century and a half into the future, looking back on how the production of
"ectogenic" babies had transformed the world:
The effect on human psychology and social life
of the separation of sexual love and reproduction…is by no means wholly
satisfactory. The old family life had certainly a good deal to commend
it…On the other hand…the small proportion of men and women who are
selected as ancestors for the next generation are so undoubtedly superior to
the average that the advance in each generation…from the increased
output of first-class music to the decreased convictions for theft, is very
startling.
Dædalus was a popular and influential book,
the original dose of "future-shock" for the 20th century. It inspired Aldous
Huxley's novel Brave New World
(1932), in which a society based on test-tube babies turns out to be not such
a wonderful place after all. Huxley also put Haldane in another of his novels,
Antic Hay (1923), as Shearwater, "the biologist too absorbed in his
experiments to notice his friends bedding his wife."
By the mid-1930s, leading geneticists such as Hermann
Muller announced that in vitro ("in glass") fertilizations would soon
be possible, and 40 years later they were a reality. Yet, though he predicted
its feasibility, Haldane became an outspoken critic of eugenics. Genetic theory was being
used for distorted political ends, he complained, by "ferocious enemies of
human liberty."
Shortly before his death in 1964, the irrespressible
Haldane wrote an outrageous
comic poem while in
the hospital, mocking his own incurable disease:
Cancer's a Funny Thing:
I wish I had the voice of Homer
To sing of rectal carcinoma,
Which kills a lot more chaps, in fact,
Than were bumped off when Troy was sacked…
It was circulated among his friends, who savored the
consistently witty irreverence with which Haldane had lived his courageous
and productive life.
[ Richard Milner,
The
Encyclopedia of Evolution, NY: Facts on File, 1990, pp. 207-08. ]
Gould on J. B. S. Haldane
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J. B. S. Haldane and the Initial Pluralism of the
Synthesis.—Haldane purposely included a plural in the title of his
book—The Causes of
Evolution (1932)—for he believed that nothing so
encompassing could be so unifactorial. But Haldane wrote his book in the
tradition of restriction, primarily to debunk Kellogg's triad of alternatives by
showing the power of natural selection. He states (p. v) that his book
began as a series of lectures entitled "A Re-examination of Darwinism," and
he then announces his primary aim in the preface (p. vi): "To prove that
mutation, Lamarckian transformation, and so on, cannot prevail against
natural selection of even moderate intensity." (Haldane treats the same
subject more formally in the book's lengthy mathematical appendix, thus
uniting both the front and back matter for a single purpose.)
Haldane presents a conventional account of the
revivification of Darwinism and the rejection of alternatives. Darwinism had
fallen on bad times before the synthesis: "Criticism of Darwinism has been so
thoroughgoing that a few biologists and many laymen regard it as more or less
exploded" (p. 32). The Darwinian resurrection followed from the recognition
that continuous, small-scale variation could also claim a Mendelian basis
(p. 71) and, especially, that tiny selection pressures, working in a
cumulative manner on such minor variations, could effectively explain all
evolution: "But however small may be the selective advantage the new character
will spread, provided it is present in enough individuals of the population to
prevent its disappearance by mere random extinction.…An average
advantage of one in a million will be quite effective in most species" (1932,
p. 100). The development of mathematical population genetics establishes
the centerpiece of Darwinian revival. Haldane even begins the tradition of
a founding trinity in stating, however immodestly (p. 33): "I can write of
natural selection with authority because I am one of the three people who
know most about its mathematical theory."
However, in contrast to Fisher's quest for pervasive and
abstract generality, Haldane felt compelled to bring the smaller and more
particular puzzles of natural history under his theoretical umbrella. Here he
allows a substantial range of exceptions to Darwinism, albeit at subsidiary
frequency—thus illustrating the predominant pluralism of the early
synthesis. Haldane rejects Lamarckism outright, as contrary in principle to
the known workings of inheritance. But, in a remarkable passage, he finds
some space, in chinks and corners of the new world of fusion between Darwin
and Mendel, for the two internalist theories in Kellogg's triad of
alternatives—saltation and orthogenesis. (In fact, Haldane even repeats
the "standard" anti-Darwinian claim for selection's merely subsidiary and
negative role in enhancing and stabilizing a saltational change arising by
other means—even though Haldane regards this alternative mechanism as
rare in nature.) Galton's polyhedron cannot be fully rounded by the emerging
Darwinian consensus:
But if we come to the conclusion that natural
selection is probably the main cause of change in a population, we certainly
need not go back completely to Darwin's point of view. In the first place, we
have every reason to believe that new species may arise quite suddenly,
sometimes by hybridization, sometimes perhaps by other means. Such species
do not arise, as Darwin thought, by natural selection. When they have arisen
they must justify their existence before the tribunal of natural selection,
but that is a different matter.…Secondly, natural selection can only
act on the variations available, and these are not, as Darwin thought, in
every direction. In the first place, most mutations lead to a loss of
complexity (e.g. substitution of leaves for tendrils in the pea and
sweet pea) or reduction in size of some organ (e.g. wings in
Drosophila).…Mutations only seem to occur along certain lines
(1932, pp. 138-139).
Two modes of non-Darwinian change especially intrigued
Haldane. First, though he tried to reinterpret as many cases as possible in
a Darwinian manner, Haldane accepted some paleontological claims for
supposedly orthogenetic trends, and he admitted that the developing Darwinian
synthesis could find no place for such phenomena: "Many such cases—for
example the development of large size or large horns—can, I think, be
put down to the ill effects of competition between members of the same
species. Others, such as the exaggerated coiling of Gryphaea cannot at
present be explained with any strong degree of likelihood" (1932, p. 141).
(This example seems especially ironic in retrospect, because Gryphaea's
supposed overcoiling to necessary extinction never occurred, and the claim
rested upon misreported and misinterpreted data….)
As his favorite general argument for awarding a small space
to orthogenesis, Haldane cited the putatively higher frequency of
degenerational over progressive evolution, arguing that such a tendency
probably required an internalist explanation rooted in a bias for deletional
mutations: "Degeneration is a far commoner phenomenon than progress. It is
less striking because a progressive type, such as the first bird, has left
many different species as progeny, while degeneration often leads to
extinction, and rarely to a widespread production of new forms…But if we
consider any given evolutionary level we generally find one or two lines
leading up to it, and dozens leading down" (1932, pp. 152-153).
Second, Haldane accepted the common wisdom of taxonomists
in his generation that most differentia of species expressed no adaptive
significance. He also acknowledged this factual substrate as a primary source
of legitimate doubts, then common among taxonomists, about Darwinism. "But
when we have pushed our analysis as far as possible, there is no doubt that
innumerable characters show no sign of possessing selective value, and,
moreover, these are exactly the characters which enable a taxonomist to
distinguish one species from another. This had led many able zoologists and
botanists to give up Darwinism" (1932, pp. 113-114).
Haldane even presents the interesting argument that we have
been fooled into accepting a dominant frequency for adaptation by a pronounced
bias in the fossil record—the differential preservation of species with
persistently large populations subject to control by small Fisherian
differentials in natural selection. Perhaps most species exist as much smaller
populations, and therefore become subject to Wrightian dynamics of genetic
drift—even if such species rarely enter the fossil record and therefore
fail to leave evidence for their dominant relative frequency. Haldane even
cites the highest of all authorities to buttress this idea:
But Wright's theory certainly supports the view
taken in this book that the evolution in large random-mating populations, which
is recorded by paleontology, is not representative of evolution in general,
and perhaps gives a false impression of the events occurring in less numerous
species. It is a striking fact that none of the extinct species, which, from
the abundance of their fossil remains, are well known to us, appear to have
been in our own ancestral line. Our ancestors were mostly rather rare creatures.
"Blessed are the meek: for they shall inherit the earth" (1932, pp.
213-214).
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[ Stephen Jay Gould, The
Structure of Evolutionary Theory. Cambridge, MA: Harvard Univ.
Press, 2002, pp. 514-515. ]
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