In a forest full of white birch trees lived a large number of mostly white moths with a few gray
spots on them (some had more spots the others). The spotted white moths would land on the
birch trees and it was hard to see them because they blended in so well. It made it difficult for
the birds (who wanted to eat them) to find them. When the industrial revolution came, the
nearby factories gave off lots of smoke and over time the white birch trees became more and
more covered with the soot from the smoke. They trees began to look more and more gray.
Over this time, it was noticed that the white moths with gray spots, became more and more
gray looking in response to this change in their environment. Give a detailed description of
how and why the moths turned more and more gray over time. You may want to use terms
such as adaptation, survival of the fittest and others from this unit and other questions on this
test. (5 points)