Prior to 1800 in England, the typical moth of the speciesBiston betularia(peppered moth) had a light pattern. Darkcolored moths were rare. By the late 19th century, thelight-colored moths were rare, and the moths with dark patternswere abundant.
The cause of this change was hypothesized to be selectivepredation by birds (JW Tutt, 1896). During the industrialrevolution, soot and other wastes from industrial processes killedtree lichens and darkened tree trunks. Thus, prior to the pollutionof the industrial revolution, dark moths stood out on light-coloredtrees and were vulnerable to predators. With the rise of pollution,however, the coloring of moths vulnerable to predators changed tolight.
In the late 1900s, England cleaned up its air, and pollutiondecreased. The bark of trees went from dark to light.
Which of the following outcomes to the populations of pepperedmoth would you expect given this environmental change?
