Question

Which organisms are found on the bark of trees as indicators of pollution free environment?Why?​

Answer 1

white moth

the presence of white moth indicate pollution free environment .

Moth turns from black to white as Britain's polluted skies change colour. The moth was white with small black speckles but over time it evolved to being almost black in parts of the UK because of heavy industrial pollution. The change made it less obvious to predators against backgrounds of grime and soot