Question: The passage given below is followed by four summaries. Choose the option that best captures the author’s position.
North American walnut sphinx moth caterpillars (Amorpha juglandis ) look like easy meals for birds, but they have a trick up their sleeves- they produce whistles that sound like bird alarm calls, scaring potential predators away. At first, scientists suspected birds were simply started by the loud noise. But a new study suggests a more sophisticated mechanism the caterpillar’s whistle appears to mimic a bird alarm call, sending avian predators scrambling for cover. When pecked by a bird, the caterpillars whistle by compressing their bodies like an accordion and forcing air out through specialized holes in their sides. The whistles are impressively loud-they have been measured at over 80 dB from 5cm away from the caterpillar-considering they are made by a two-inch long insect.
Option 1 is incorrect. It does not mention that the caterpillars are a surprising example of how the sound produced is not a random sound but one that mimics alarm calls for birds. Eliminate option 1.
Option 2 is incorrect as the option misses the most important point of the précis – that the caterpillar sounds mimic avian alarm calls. Eliminate option 2.
Option 3 is correct. The caterpillars use “acoustic deception” to defend themselves by making bird alarm calls. This is the precise point of the précis. Retain option 3.
Option 4 is incorrect. The writer does not indicate that caterpillars resort to camouflage in the use of this defence mechanism. Eliminate option 4.
Hence, the correct answer is option 3.