In Response to: A Cicada Reunion

In his essay “Of Bamboo, Cicadas, and the Economy of Adam Smith,” paleontologist and expansive thinker Stephen Jay Gould tackled the question of cicada life cycles (13- and 17-year). In essence, the advantage of a prime number life cycle for cicadas is to be “off cycle” from other predators with shorter life durations. Gould gives the example of cicadas that emerge every 17 years facing a predator with a five-year life cycle. Cicadas would only meet a peak predator population every 85 years (5x17) giving an advantage to the cicadas.

So not only can cicadas count, they understand prime numbers.

To this mathematical marvel of nature, add Smithsonian Magazine’s report on the recent discovery of the gender-bending, death-zombie fungus that causes five percent of Brood X cicadas to exhibit hypersexual behavior even as spore balls replace the genitals of the insect.

David Theis ’78
Piedmont, Calif.