In Pursuit of the Gene

132 ¨ MENDEL WARS
fused his offer, hoisting the issues of Biometrika over his head and offering
them as evidence of the folly of the biometric school. 32 According to the
official record, however, it was the highly revered Darwinian, Reverend
T. R. R. Stebbings, 33 not Bateson, who expressed his wish to see the controversy
rage on because “from it the world could only gain in light,” and this
view was enthusiastically seconded by the chairman, who added that “the
debate had been of much value to those biologists who were still sitting on
the fence.” 34 Even a half century later, Bateson’s Cambridge colleague R. C.
Punnett could still taste the victory of the day, recalling that “Bateson’s
generalship had won all along the line and thenceforth there was no danger
of Mendelism being squelched out through apathy or ignorance.” 35
That fall Bateson discovered a major flaw in Darbishire’s experiment
purporting to prove that the percentage of albinos among the progeny
of hybrid parents depended on the number of albinos in the grandparent
generation. Remarkably, Darbishire had failed to distinguish between pigmented
homozygotes and heterozygotes among allegedly “hybrid” parents,
and as a result some of them actually contained no albino gene. Properly
interpreted, Darbishire’s results were perfectly consistent with the Mendelian
model of segregation of hybrids after all: the smaller the number of albino
grandparents in a series of crosses, the greater the number of undetected
homozygotes among the parents and the smaller the number of
albino grandchildren.
¨ THE LAST MAJOR CONFRONTATION between the warring camps
was again over the vexing question of the inheritance of coat color, this
time in horses. Already in a paper published in March 1900, days before the
rediscovery of Mendel, Pearson had taken his first stab at the problem. With
the aid of Weatherby’s studbook, which gave a complete record of the coat
color and ancestry of all the registered thoroughbred horses in England, he
had computed the degree of similarity in coat color between relatives of
different degrees and concluded that the inheritance of horse coat color did
not obey either Galton’s ancestral law or the revised form that he had introduced
in 1899. 36
In 1903 Pearson had again returned to the coat color problem, intro-