Marine biologist Dr. Elena Costa theorizes that dolphins use their signature whistles not just for individual identification but also to call specific pod members by name. She has observed that dolphins will respond more readily when their personal whistle is played than when other dolphins' whistles are used.
Which observation would provide the strongest evidence for Costa's theory about dolphins calling each other by name?
Dolphins have been observed producing another dolphin's signature whistle while looking for that specific individual
Dolphins can produce over 50 different vocalizations
Young dolphins take years to develop their unique signature whistles
Dolphins in captivity whistle more frequently than wild dolphins
Correct Answer: A
Choice A is the best answer. This observation shows dolphins using another's whistle to summon that specific individual—exactly what "calling by name" means.
- Context clues: The theory is about calling others "by name."
- Evidence evaluation: Producing another's whistle while searching = calling their name.
- Verify: This is functionally identical to calling someone's name.
💡 Strategy: Look for behavior that demonstrates the claimed function.
Choice B is incorrect because having many vocalizations doesn't prove they use them as names. Choice C is incorrect because development time doesn't show how whistles function as names. Choice D is incorrect because frequency differences are irrelevant to the naming theory.