Question

Two species of birds, A and B, are found together in region X. Only species A is present in region Y. Both species produce species-specific alarm calls in response to a predator P. A researcher conducts experiments where she plays recorded calls of both species to species A in regions X and Y. The response of species A to the recorded calls are summarized in the table below. . Call stimulus Response in region X Response in region Y Alarm call of species A Species A flies for cover Species A flies for cover Alarm call of species B Species A flies for cover Species A does not respond Based on the results, the most appropriate inference is that

• A. species A’s response to species B’s alarm call is a learned behavior.
• B. species A’s response to species B’s alarm call is an innate behavior.
• C. predator P is absent in region Y.
• D. predator P exclusively preys on species B

Hint:

Think “\textbf{S}pecies richness up with \textbf{S}ize and \textbf{S}hort distance.” Large + near wins; small + far loses.

Answer 1

The Correct Option is A

Step 1: Use responses to A’s own call as a control (innate baseline).
Species A flies for cover to \emph{A’s} alarm call in \emph{both} regions X and Y. Hence, responding to its \emph{own} call is likely innate (does not require prior experience with B).

Step 2: Compare responses to B’s call across regions.
- In region X (A and B coexist), A does fly for cover to B’s call.
- In region Y (B absent), A does not respond to B’s call.

Step 3: Inference about the mechanism.
A differential response that appears only where A has opportunity to experience B’s calls (region X) indicates learning or experience-dependent association (social learning or conditioning). If the response were innate, A would respond to B’s call in both regions.

Step 4: Rule out alternatives.
- (C) “Predator \(P\) is absent in region Y” is unsupported; A still responds to its own alarm call there, indicating perceived risk.
- (D) “\(P\) exclusively preys on B” is irrelevant; A’s learned eavesdropping on B’s alarm call better explains the pattern. Final Answer:
\[ \boxed{\text{(A) Learned response of species A to species B's alarm call}} \]