13 Facts About Bernard Kettlewell

Henry Bernard Davis Kettlewell was a British geneticist, lepidopterist and medical doctor, who performed research on the influence of industrial melanism on peppered moth coloration, showing why moths are darker in polluted areas.

Bernard Kettlewell worked as an anaesthetist at St Luke's Hospital, Guildford.

Bernard Kettlewell emigrated to South Africa during 1949, and from then until 1954 was a researcher at the International Locust Control Centre at Cape Town University, investigating methods of locust control and going on expeditions to the Kalahari Desert, the Knysna Forest, the Belgian Congo, and Mozambique.

Bernard Kettlewell was assigned to investigate peppered moth evolution under the supervision of E B Ford.

Bernard Kettlewell's grant was to study industrial melanism in general and in particular the peppered moth Biston betularia which had been studied by William Bateson during the 1890s.

Bernard Kettlewell showed that the birds ate the moths, and found that if the camouflage of the moths made them difficult for him to see against a matching background, the birds too had difficulty in finding the moths.

Bernard Kettlewell demonstrated experimentally the efficiency of natural selection as an evolutionary force: light-coloured moths are more conspicuous than dark-coloured ones in industrial areas, where the vegetation is darkened by pollution, and are therefore easier prey for birds, but are less conspicuous in unpolluted rural areas, where the vegetation is lighter in colour, and therefore survive predation better.

Bernard Kettlewell's experiment resulted in better understanding of industrial melanism and its effects on the evolution of species, and can be seen as an important example of urban evolution.

Haldane was of the opinion that Bernard Kettlewell had attempted to capitalise on Haldane's own observations, made as early as 1924, of the statistical probability of rate of change from light to melanic forms of the peppered moth.

Bernard Kettlewell suspected that Kettlewell trained the birds to pick moths on tree trunk, where they were not normally present.

Bernard Kettlewell's experiments have been vindicated by elaborate research, and the genetic details of the evolutionary process established.

Bernard Kettlewell's work, published posthumously in 2012, provided new data which answered criticisms and validated Kettlewell's methodology.

Bernard Kettlewell fell off a birch tree in 1978 while conducting a field collection and fractured two vertebrae in his back.