Question 76·Easy·Inferences
Biologist Anika Gupta monitored two populations of field mice for five years. One population occupied open grasslands where hawks frequently hunt, and the other occupied dense shrubs where hawks are rarely observed. In the grassland population, about 70 percent of the mice had a light, sandy coat, whereas in the shrub population only about 15 percent did. Gupta also recorded that, within the grassland population, light-colored mice were captured by hawks far less often than dark-colored mice were.
Taken together, these observations most strongly suggest that _____
Which choice most logically completes the text?
For SAT inference questions in science passages, first restate the question in your own words, then list the key observations (numbers, comparisons, and relationships). Ask what simple relationship or trend those observations point to, without adding outside knowledge. Finally, test each answer choice: keep the one that is directly supported by the given data, and reject any that introduce new causes, predict the future, or discuss ideas (like specific evolutionary mechanisms) that the passage never mentions.
Hints
Focus on the data pattern
Look carefully at how the percentages of light-colored mice differ between grasslands and shrubs, and how often light versus dark mice are captured by hawks.
Think about cause and effect
Ask yourself: Given the observations, what relationship between coat color, habitat, and hawk predation seems most likely? Which trait appears to affect which outcome?
Beware of extra, unsupported ideas
Eliminate any answer choice that talks about reasons for hawk behavior, future changes, or processes in the shrub population that the passage never mentions.
Step-by-step Explanation
Restate what the question is asking
The question asks what conclusion is most strongly suggested by the observations. That means we must find the choice that is best supported by the specific information given, without adding new, unsupported ideas.
Summarize the key observations
List the important facts from the passage:
- There are two mouse populations: one in open grasslands (many hawks) and one in dense shrubs (few hawks).
- In grasslands, about 70% of the mice are light, sandy colored.
- In shrubs, only about 15% of the mice are light, sandy colored.
- Within the grassland population, light-colored mice are captured by hawks far less often than dark-colored mice. These details connect mouse coat color, habitat type, and how often hawks catch the mice.
Infer the relationship among coat color, habitat, and hawk predation
Ask: What pattern do these observations suggest?
- In grasslands, where hawks hunt often, most mice are light-colored and light-colored mice are less often caught.
- In shrubs, where hawks are rarely seen, far fewer mice are light-colored. This pattern suggests that in the open grasslands, coat color affects how likely a mouse is to be caught by a hawk, and that lighter color seems to be associated with better survival there.
Match the best-supported inference to an answer choice
Now compare the choices to the pattern you identified, and eliminate any that go beyond the data (for example by predicting the future or inventing new causes). The only choice that is directly supported by the observations—that in grasslands, most mice are light-colored and those mice are caught less often by hawks—is D) having a light, sandy coat may help field mice avoid hawk predation in open grasslands.