Evolution Question 38
38. Industrial melanism as observed in peppered moth proves that
[2007]
(a) the melanic form of the moth has no selective advantage over lighter form in industrial area
(b) the lighter-form moth has no selective advantage either in polluted industrial area or non-polluted area
(c) melanism is a pollution-generated feature
(d) the true black melanic forms arise by a recurring random mutation
Show Answer
Answer : d
Hints & Solution
(d) During the period when the number of coal-burning factories in England was increasing (during the so-called Industrial Revolution) it was noticed that the number of melanic individuals of the species of Peppered Moth (Biston betularia) was becoming more common. Originally rare in the population of normally light-colored moths, the frequency of the melanic form increased in polluted areas until it was over $90 %$. This change in color has come to be known as “industrial melanism.”
