Self-study
If one of the effects of a genetic mutation makes a substantial contribution to the survival of the species, then, and only then, will that mutation be favored in natural selection. ████ ███████ ██ ███████ ██ ███ ████████ ██████ ████ ███ ██████ ████ ████ ███ ████████ ███ ████ ███████ █████ ██ █ █████ ████ ███ ████████ ████ ███ ██ ██ ████████ ██ ██ █████ ███ ████████ ██ ██████ ███ ████ ███████ ██████
Summary
If one effect of a genetic mutation contributes substantially to survival of a species, that mutation will be favored in natural selection. In addition, if a mutation is favored in natural selection, that means at least one effect of that mutation contributes substantially to survival of a species.
The rules above are subject to one exception — when the effect of traits that are carried along with the genetic mutation are so negative that they cancel out the benefits of a mutation, the mutation won’t be favored.
Notable Valid Inferences
There’s no clear inference to draw. We just need to understand the complicated rules in the stimulus accurately. The correct answer will be something that contradicts what we know, since this is a Must Be False question.
17.
If the statements above are █████ ████ ██ ███ █████████ █████ ██ ████ ███████
a
A species possesses █ █████ █████ ███████ ███ ███ ███████ ███ ███ ████████ ██ ████ ████████
Could be true. A species can have a trait with only neutral effects. This just implies the trait won’t be favored by natural selection.
b
All the effects ██ ████ ███████ █████████ ██████████ █████████████ ██ ███ ████████ ██ █ ████████
Could be true. There could be some mutations that only do very helpful things for survival. These mutations will be favored.
c
A species possesses █ █████ ████ ███████ ███ ████████ ████████ ██████████
Could be true. A species can have a trait that reduces survival potential. This trait won’t be favored.
d
A genetic mutation ████ ███████ █████ ███████ ████████ ██████ ██ ███████ ██ ███████ ██████████
Could be true. A genetic mutation can carry several negative traits. And that mutation can still be favored as long as the negative traits aren’t so negative as to outweigh the benefits of the mutation.
e
A genetic mutation █████ ███████ ███ ███ ███████ ██ █ ███████ ██ ███████ ██ ███████ ██████████
Must be false. If the effects are all neutral, then the mutation won’t be favored. One requirement to be favored is that one effect contributes substantially to survival.