Question

Difficulty: MediumCommand of Evidence: Textual

Cooperative hunting between different species is rare, but Nassau groupers (*Epinephelus striatus*) and moray eels (*Gymnothorax moringa*) are known to hunt together. When a prey fish escapes into a narrow crevice in the coral reef where the grouper cannot reach, the grouper will often locate a moray eel and perform a rapid head-shaking gesture. Marine biologist Dr. Liam Chen hypothesized that groupers employ this signaling behavior specifically as a targeted recruitment strategy to solicit help for extracting inaccessible prey, rather than as a general response to the presence of potential prey in the area.

Which finding, if true, would most directly support Dr. Chen's hypothesis?

  1. A
    Groupers and moray eels capture significantly more prey per hunt when cooperative hunting than when either species hunts individually.
  2. B
    Cooperative hunting behaviors are common among many predatory fish species inhabiting coral reef ecosystems.
  3. Groupers frequently perform the head-shaking gesture when a prey fish is hidden in a crevice, but they rarely do so when an equivalent number of prey fish are visible in open water.Answer
  4. D
    Moray eels that have been recruited via the head-shaking gesture are more likely to share their captured prey with groupers in future hunts.

Answer

The correct answer is the option stating that groupers frequently perform the head-shaking gesture when a prey fish is hidden in a crevice, but they rarely do so when an equivalent number of prey fish are visible in open water.
The finding that groupers frequently signal when prey is hidden in a crevice, but rarely do so when prey is in open water, directly supports the hypothesis. It demonstrates that the gesture is a targeted response to prey inaccessibility rather than a general response to prey presence.

Step-by-Step Solution

1
Identify the core hypothesis proposed by Dr. Liam Chen in the passage.
Dr. Chen hypothesized that groupers perform the head-shaking signal specifically to recruit moray eels when prey is inaccessible in crevices, rather than as a general reaction to prey presence.
Understanding the precise claim is necessary to determine what evidence would support it.
2
Evaluate the kind of evidence needed to support this hypothesis.
Evidence should show a contrast in signaling frequency: high frequency when prey is inaccessible, and low frequency when prey is accessible (open water) despite prey being present.
This contrast isolates prey inaccessibility as the specific trigger for the signaling behavior.
3
Assess the choices to find the one that matches the required evidence.
The finding that groupers signal frequently when prey is in a crevice but rarely when prey is in open water matches this requirement, while other options focus on general hunting success, other species, or speculative future behaviors.
Selecting the correct option requires identifying the finding that logically connects to and reinforces the specific claim.

Key Concept

Identifying textual evidence that supports a specific hypothesis or claim
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