Peppered Moths: Evidence for Evolution or Trivial Change?

This dark peppered moth stands out against a light background.

Biologist Jonathan Wells has penned an important update to the discussion over the legitimacy of using the peppered moth story in biology textbooks to provide evidence for Darwinian evolution. He writes:

Before the industrial revolution, most peppered moths in England were light-colored; but after tree trunks around cities were darkened by pollution, a dark-colored ... variety became much more common.... In the 1950s, British physician Bernard Kettlewell performed some experiments that seemed to show that the proportion of ... [dark] moths had increased because they were better camouflaged on darkened tree trunks and thus less likely to be eaten by predator