.STRUCTURE IS Curing Americans to all type of eyeglasses. On April 8th millions observed a total solar eclipse. A lot of will definitely be less mesmerized when, in the coming days, trillions of cicadas seem in the nation's Midwest and south-east. The swarm will certainly be actually unusually huge given that two kinds of the pest-- Family XIII and Family XIX-- are surfacing simultaneously. The last time they showed up together remained in 1803, when Thomas Jefferson was actually president. Why carry out the cicadas have such an unique life process?