Alas for [Kettlewell]'s experiment, but fortunately for science, which lives by self-correction, Theodore David Sargent, now a professor emeritus of biology at the University of Massachusetts at Amherst, tried from 1965 to 1969 to replicate the part of Kettlewell's experiment that showed how moths choose on which part of a tree trunk to alight. Sargent couldn't do it. He found that the moths' resting places were not matters of individual choice, as Kettlewell believed, but were genetically determined. Other naturalists showed that birds do not pick moths from tree trunks.
[Judith Hooper]'s tale is engrossing. Contemporary scientists increasingly do not work alone, and she describes with finesse the milieus in which Kettlewell especially and also Sargent did their work. Kettlewell's was that of snobbish, high-table Oxford, in which, as a gifted amateur, he never felt quite at home. He was dominated by the powerful and haughty scientist E.B. Ford. An unhappy child, Kettlewell lived a troubled life and committed suicide in 1979. Despite the doubts about his major experiment, no one doubted that he was a brilliant field naturalist in the British tradition of ardent amateurs.