Which insect emerges from underground once every 13 or 17 years?
And the answer: cicada.
There are more than 3,000 species of cicadas around the world. Most make an appearance every year, with males buzzing loudly from trees. However, in eastern North America, there are also cicadas that appear only once every 13 or 17 years.
Brood X (Brood 10), the Great Eastern Brood, is one of 15 broods of periodical cicadas that appear regularly throughout the eastern United States. It has the greatest range and concentration of any of the 17-year cicadas. Every 17 years, Brood X cicadas tunnel to the surface, lay eggs, and die off in several weeks. Their very brief above-ground period combined with such a lengthy dormancy makes hunting these insects a challenge -- no specialized predators can truly adapt to such a highly absent species.
There is also evidence to suggest that their prime number cycle helps protect the species and allows them to successfully repopulate. The theory argues that having a prime numbered life cycle keeps them out of sync with the life cycle of predators, which prevents any particular kind of predator from being too dependent on the cicadas for food. In other words, predators with one, two, four, or even eight-year life cycles won’t get too used to catching cicadas that show up only once every 13 or 17 years.
The next Brood X year on the calendar is 2021. Visit this site to see the cicada hotspot closest to you.