Simplify the following text for a Grade 10 native English-speaking person.
Original: Originally , the vast majority of peppered moths had light colouration , which effectively camouflaged them against the light-coloured trees and lichens which they rested upon .
Simplified: At first , many of peppered moths had light coloration , which made them camouflaged them against the light-colored trees and lichens which they rested upon .