Question

Which type of the selection is industrial melanism is observed in moth, Biston bitularia ?

• A. Stabilising
• B. Directional
• C. Disruptive
• D. Artificial

Answer 1

The correct option is B Directional

• Stabilizing selection results in a decrease of a population’s genetic variance when natural selection favors an average phenotype and selects against extreme variations.
• In directional selection, a population’s genetic variance shifts toward a new phenotype when exposed to environmental changes. Thus, industrial melanization is an example of directional selection.
• Disruptive selection increases genetic variance when natural selection selects for two or the more extreme phenotypes that each has specific advantages.
• Artificial selection mimics natural selection in that certain traits are chosen to be passed down to the next generation.

So, the correct answer is 'Directional'.