In 1953 Bernard Kettlewell performed a set of experiments that proved that predation by birds was responsible for the peppered moth population changing from mostly white to mostly black. The reasoning was that industrial pollution had caused the barks of trees to turn dark. Therefore black moths resting during the day on the darkened trunks of trees had a selective advantage over white moths, because the birds could see the white moths more easily and prey on them. Kettlewell released both white and black moths into the wild and demonstrated that the black moths survived at a higher rate in the polluted areas. Now you can duplicate Kettlewell's experiment with the Evolution of the Peppered Moth Science Kit
, available from Boreal Laboratories. There's just one problem. Some are beginning to say that the case of the peppered moth may be one of the biggest cases of scientific fraud of the twentieth century, up there with the Piltdown Man
. You see, moths tend not to rest on tree trunks during the day; their main predators are bats, not birds; and anyway, birds see more in the UV range than people do, so what looks camouflaged to us may not look so to a bird. Given this, how did Kettlewell achieve his suspiciously perfect results? Rumors of fraud are in the air. Kettlewell definitely still has his defenders, but if his experiments do end up in the Science Hall of Infamy, then those science kits are going to be collector's items.