Thysanoptera are sometimes called thunder flies because of what behavior?

• A. They migrate long distances
• B. They take to the air in huge numbers, especially in thundery weather
• C. They remain on trunks during rain
• D. They feed on nectar exclusively

Answer: (B)

The behavior being tested is the mass dispersal flight of thrips in response to stormy weather. Thysanoptera are tiny insects that can be carried aloft by wind and rain, leading to spectacular swarms of individuals taking to the air during thundery conditions. This dramatic, storm-associated flight is why they’re nicknamed thunderflies. The other options don’t describe this storm-driven mass ascent: they aren’t known for long-distance migration, staying on trunks during rain isn’t the characteristic behavior implied, and they don’t feed exclusively on nectar.