Summary: The Influence Of Natural Selection On Peppered Moths

For example,”The most famous of mismatched colors first came to light in the 1950s. Coal smoke had darkened England’s trees, so that light pepper moths, once blended nicely against bark, now stood out against the smudgy background. A dark form of peppered moths, once rare, became common. Researchers suspected that natural selection was the reason why, and they tested that idea by putting dark and light moth models on trees. Birds quickly attacked the mismatched ones, as had been predicted. But the evidence in favor of natural selection on peppered moths continued to accumulate. For one thing, Britain and other countries cleaned up their air in the late 1900s, and trees went from dark to light. Now natural selection’s balance shifted: black