Primed to Go in 2021!

It is predicted that billions of adult Cicadas (noisy, sap-feeding insects) will emerge in the states of New York, Ohio, Illinois and Georgia in May 2021 (https://www.theguardian.com/environment/2021/jan/26/cicadas-emerge-eastern-us). Cicadas spend most of their lives, living underground as their juvenile (nymph) form. The last major emergence in these states, was 17 years ago, in 2004. Seventeen is a prime number (one that can only be divided by itself). It has long been suggested, that the insect arranges its mass emergence in this way, because no specialist Cicada-eater could evolve to synchronise with it (it would have to wait 17 years between feasts). Cicadas still get eaten but only by relatively-unskilled non-specialists.