Mystery of the Peppered Moth
A hundred years ago, the air was clean. An 1-9
insect called the peppered moth lived in the forests 10-18
of England. It was light with dark markings. 19-26
The moth was the color of the bark on some 27-36
trees. Light-colored plants called lichens also 37-42
grew on trees. When the moth landed on the 43-51
light-colored bark or lichens, it was hard to see. 52-60
Animals that liked to eat the moth couldn’t find it. 61-70
Then people in England began building 71-76
factories. The factories burned coal. When coal 77-83
burns, it makes smoke and black soot. Factories 84-91
sent soot and smoke into the air. 92-98
Smoke and soot covered the trees. The 99-105
trees turned dark and the lichens died. No one 106-114
could find the light-colored peppered moth 115-120
anymore. Instead, all they found were 121-126
dark-colored peppered moths. 127-129
Scientists believed the peppered moth 130-134
changed color to hide itself. If a light-colored 135-142
moth landed on a dark tree, it would be easy to 143-153
spot. But if the moth were dark, it could stay 154-163
hidden. 164