Identify the examples of evolution caused due to anthropogenic actions:
A. Bacillus thuringiensis and Lepidopterans
B. Industrial melanism in moths
C. Resistant microbes against antibiotics
D. Pesticides and insects
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → B, C and D only
Anthropogenic action means human action. When human activity changes the environment, the variants that can survive it increase within a short time.
A. Bacillus thuringiensis and Lepidopterans — Incorrect. B. thuringiensis is a soil bacterium whose toxin kills lepidopteran insects. It is a natural relation used in biocontrol, not an example of evolution NCERT gives.
B. Industrial melanism in moths — Correct. Factory smoke darkened the tree trunks in England, so the dark moths escaped birds and became common.
C. Resistant microbes against antibiotics — Correct. Overuse of antibiotics leaves only the resistant microbes alive, so they multiply within months or years.
D. Pesticides and insects — Correct. Heavy use of pesticides selects the resistant insects.
NCERT Extract:
What Are the Evidences for Evolution? – “… Remember that no variant is completely wiped out. Similarly, excess use of herbicides, pesticides, etc., has only resulted in selection of resistant varieties in a much lesser time scale. This is also true for microbes against which we employ antibiotics or drugs against eukaryotic organisms/cell. Hence, resistant organisms/cells are appearing in a time scale of months or years and not centuries. These are examples of evolution by anthropogenic action.”