Terry, thanks, but when I call for a name, I’m more expecting a species name. There are numerous species of cicadas (did you notice I played with the word in the title? :), and I wonder if anybody knows this particular species. Some species emerge every ten years, some other species do it every 13 or 17 years. Some have shorter development times and even this is not a formal rule but more of an average for a given population, which results in special years where a species is really numerous compared to the other years. This is probably also an evolutionary way to escape parasites that led to speciation in different regions. With two competing species, 13 and 17 years drive cycles that have very little overlap, so these numbers have a biological meaning.