What is unique about the life cycle of periodical cicadas?

What is unique about the life cycle of periodical cicadas?

• A. They spend 2-3 years underground as nymphs.
• B. They spend 13 to 17 years underground as nymphs before emerging to mate and die shortly after.
• C. They spend their entire life as adults.
• D. They spend 5-7 years underground as nymphs before emerging.

Answer: (B)

Periodical cicadas are defined by a very long juvenile stage spent underground. They live as nymphs for an extended, prime-numbered period—either 13 or 17 years—feeding on the sap of tree roots, then emerge all at once as winged adults to mate and die within a short time. This combination of a lengthy underground life and a synchronized, brief adult phase is what sets their life cycle apart. Other options describe shorter underground periods or an entire life as adults, which don’t match what these cicadas actually do.

Periodical cicadas are defined by a very long juvenile stage spent underground. They live as nymphs for an extended, prime-numbered period—either 13 or 17 years—feeding on the sap of tree roots, then emerge all at once as winged adults to mate and die within a short time. This combination of a lengthy underground life and a synchronized, brief adult phase is what sets their life cycle apart. Other options describe shorter underground periods or an entire life as adults, which don’t match what these cicadas actually do.