Sargent (1985) suggested that some melanic moths may be adapted to exploit white backgrounds that are variegated with black, rather than the uniformly dark backgrounds suggested by the traditional explanation of industrial melanism
The phenomenon of industrial melanism
So I set up our problem: "Industrial melanism
is a fascinating example--the same effect was measured in England and the northeastern United States in the same species as pollution increased, and then the trend reversed on both sides of the Atlantic following clean-air legislation.
Kettlewell claimed a higher survival rate for moths that had developed a form industrial melanism
(blackened wing-tip patterns) via selective breeding patterns in coal producing industrial regions of England over their lighter-coloured predecessors who were in state of population decline.
principle that forms the basis for the phenomenon of industrial melanism
Kettlewell's results, published in 1959, seemed to prove that industrial melanism
was a fact.