Q. Which one of the following phenomena supports Darwin’s concept of natural selection in organic evolution?
(a) Production of ‘Dolly’, the sheep by cloning
(b) Development of organs from ‘stem cells’ for organ transplantation
(c) Development of transgenic animals
(d) Prevalence of pesticide resistance insects
Solution :
Correct option : D Prevalence of pesticide resistant insects supports natural selection theory, e.g., DDT was though to be an effective insecticide against household pests (like mosquitoes houseflies, body ice, etc.) in 1945. But, within 2 to 3 years of its introduction, new DDT resistant mosquitoes appeared in the population. These mutant stains, soon became well established in the population by natural selection and thus replaced the original DDT-sensitive mosquitoes .So, the correct answer is ‘Prevalence of pesticide resistance insects’.
