What order of events would show how natural selection occurred in a population of lice that could originally be controlled by the chemical permethrin?
A) A louse population evolves resistance to permethrin; permethrin is used to kill lice; lice become more common in schoolchildren.
B) Some lice are resistant to permethrin; permethrin is used to kill lice; lice resistant to permethrin become the most common type.
C) Permethrin resistance is common in lice; permethrin is used to kill lice; most lice become sensitive to permethrin.
D) Permethrin is used to kill lice; individual lice change in order to survive exposure to permethrin; most lice become resistant to permethrin.

Question

Quizplus · Accepted Answer

This option correctly demonstrates natural selection occurring in the louse population. Some lice have a genetic variation that makes them resistant to permethrin. When permethrin is used to kill lice, only the non-resistant lice are killed, leaving the resistant lice to reproduce and pass on their resistance to the next generation. Over time, the population of lice becomes dominated by those that are resistant to permethrin.

What Order of Events Would Show How Natural Selection Occurred