You conduct an exercise in the Darwinian Snails Sim-U-Text lab. You simulate conditions under which survival of snails is selective-that is, snails with thicker shells are less likely to be preyed on...

Extracted text: You conduct an exercise in the Darwinian Snails Sim-U-Text lab. You simulate conditions under which survival of snails is selective-that is, snails with thicker shells are less likely to be preyed on by crabs than snails with thinner shells. The default settings also ensure the trait is heritable, and the population has variation in this trait. You allow mutations to occur. As you run the simulation, you observe that the mean shell thickness of the population increases over successive snail generations. Have you successfully simulated natural selection? No, because no snails appeared with thicker shells than the thickest shells observed in the initial population O Yes, because crabs preyed on the snails O No, because you cannot have selection with mutations operating No, because the changes in shell thickness could have been due to genetic drift O Yes, because there was a change in the mean shell thickness Yes, because there were mutations