A question about one researcher’s response to another tests how their claims and reasons connect. Read the question to find who answers whom, then summarize each study’s conclusion and evidence. Use those summaries to predict the response: reject the conclusion, add a limit to it, or build on it. Then check that the reason comes from the responding researcher’s study. A choice can take the right stance but support it with a reason that researcher never gives.
Hints
- Hint 1
Separate Nandakumar’s observation from her conclusion. What pattern did she see, and what did she say it meant?
- Hint 2
Use the two nectar groups in Ruiz’s experiment to test Nandakumar’s conclusion. What happened to each group at the temperatures described?
Step-by-step
Compare the claim with Ruiz’s evidence
Step 1Separate the observation from the claim
Nandakumar found that the birds entered their deepest torpor on the coldest nights. What does she take that pattern to show? She concludes that low nighttime temperature is the primary trigger for torpor. The question asks for Ruiz’s response to that claim about what starts torpor, not the benefit of saving energy.
- Step 2
Compare Ruiz’s test groups
What does Ruiz’s experiment add? He reports that nighttime temperature and access to nectar were varied independently, so he can separate their effects. Birds with unrestricted nectar rarely entered deep torpor, even at the lowest temperature tested, while birds with limited nectar often did so at milder temperatures. This points to stored energy as the more direct trigger, although Ruiz says that cold can make birds use more energy and so could drain their reserves. He would reject cold as the primary trigger, not deny every effect of cold.
- Step 3
Check what the field observations can show
Can Nandakumar’s observations show that cold is the primary trigger for torpor? Her cold-night pattern doesn’t separate cold itself from the birds’ low stored energy, so it can’t identify which factor starts torpor. The choice about depleted energy reserves, meaning stored energy that’s been used up, names what her observations don’t tell us. Choice A.