Consider the following two scenarios: 1) A flash- flood sweeps through an area and random lemmings are killed, resulting in a change in lemming phenotype in subsequent generations; 2) A flash- flood sweeps through an area and some lemmings are able to survive because they are able to hold their breath longer than other lemmings, resulting in a change in lemming phenotype in subsequent generations. What are the primary differences between the two scenarios?
A) Scenario 1 represents natural selection, while Scenario 2 represents genetic drift.
B) Both scenarios represent genetic drift.
C) Both scenarios represent natural selection.
D) Scenario 1 represents genetic drift, while Scenario 2 represents natural selection.

Question

Quizplus · Accepted Answer

Scenario 1 is an example of genetic drift because the change in the lemming population is due to a random event that does not necessarily select for a specific trait. Scenario 2 is an example of natural selection because the lemmings that survive and reproduce are those with a specific advantageous trait (the ability to hold their breath longer), leading to a change in the population's phenotype over generations.

Consider the Following Two Scenarios: 1) a Flash- Flood Sweeps