.STRUCTURE IS Curing Americans to all kinds of spectacles. On April 8th millions watched an overall sunlight eclipse. Numerous will certainly be actually much less knocked out when, in the coming days, trillions of cicadas appear in the country's Midwest as well as south-east. The swarm will definitely be abnormally sizable given that pair of types of the bug-- Brood XIII as well as Brood XIX-- are actually emerging simultaneously. The last time they seemed all at once remained in 1803, when Thomas Jefferson was actually head of state. Why perform the cicadas have such an unique life cycle?