Two students describe natural selection to their classmates. Student 1 describes that individuals are able to evolve to fit their changing environment and thus result in populations that are well adapted over time. Student 2 proposes that natural selection occurs when selective pressures act on individuals but evolution affects whole populations. Which student should refine their explanation of natural selection and why?

Question

Responses
A Student 1 should revise the explanation because individuals in a population cannot change the genetic component of their DNA, so they cannot evolve.Student 1 should revise the explanation because individuals in a population cannot change the genetic component of their DNA, so they cannot evolve.
B Student 1 should revise the explanation because environments cannot change enough in an individual's lifetime to see evidence of natural selection.Student 1 should revise the explanation because environments cannot change enough in an individual's lifetime to see evidence of natural selection.
C Student 2 should revise the explanation because selective pressures only act on entire populations while survival occurs with individuals.Student 2 should revise the explanation because selective pressures only act on entire populations while survival occurs with individuals.
D Student 2 should revise the explanation because it does not account for the extinction of populations after heavy selective pressures.

Answer 1

C Student 2 should revise the explanation because natural selection does act on individuals within a population, not just on entire populations. Individuals that are better adapted to their environment are more likely to survive and reproduce, passing on their advantageous traits to their offspring. This process leads to changes in the population over time, as individuals with less advantageous traits are gradually replaced. It is at the individual level that natural selection occurs, not at the population level.