If you wanted to see natural selection working in a population of mosquitoes in response to pesticide, how much pesticide should you use?
A) enough to kill most but not all the mosquitoes
B) enough to kill all the mosquitoes
C) just enough so that the mosquitoes will be exposed but not enough to kill any of them
D) enough to kill the weakest 1% of the mosquitoes

Question

Quizplus · Accepted Answer

If you use enough pesticide to kill all the mosquitoes, there will be no natural selection as there will be no surviving individuals left to reproduce. Using just enough to expose the mosquitoes without killing any will not create enough selective pressure for natural selection to occur. Similarly, using a specific threshold like killing the weakest 1% will not create enough variability in the population for natural selection to occur. The best option is to use enough pesticide to kill most, but not all the mosquitoes. This will create a selective pressure that favors individuals with traits that allow them to survive the pesticide, leading to the evolution of pesticide resistance over time.

If You Wanted to See Natural Selection Working in a Population