Why Do Cicadas Sleep for 17 Years? | Smartest Year Ever (Apr 14, 2025)

Why Do Cicadas Wait 17 Years to Emerge? The Evolutionary Secret Behind Prime Number Broods

 Cicadas don’t hibernate for 17 years—they strategically wait underground, avoiding predators with one of the most fascinating evolutionary timelines on Earth.

In this episode of Smartest Year Ever, Gordy dives into Brood XIV, the massive group of cicadas emerging in 2025 across 13 U.S. states. Why do they come out every 13 or 17 years? And why those weird prime numbers?

Turns out, it’s a brilliant move called predator satiation—and the prime-number timing may help them avoid syncing up with predator life cycles entirely. Gordy breaks it all down with vivid, weirdly satisfying logic. You'll also learn how cicadas live as root-sucking nymphs underground for nearly two decades before emerging in a synchronized, noisy, reproductive flash mob.

If you're in the eastern U.S., get ready: the ground’s about to hum.

Sources:

• U.S. Forest Service. (n.d.). Here come the cicadas!. U.S. Department of Agriculture. https://www.fs.usda.gov/about-agency/features/here-come-cicadas
  

• Live Science. (2011, May 13). Why Southern Cicadas Emerge In Exact Prime Number Cycles. https://www.livescience.com/14238-southern-cicadas-emerge-exact-prime-number-cycles.html
  

• NBC Chicago. (2024, April). Which cicada broods you will see in different parts of Illinois. https://www.nbcchicago.com/cicadas-illinois-chicago-2024/which-cicada-broods-see-different-parts-illinois-historic-emergence-begins/3428725/
  

#Cicadas #NatureFacts #Evolution #BroodXIV #17Years #Entomology #FunFacts #PrimeNumbers #SmartestYearEver

Music thanks to Zapsplat.