.TYPE IS Attending To Americans to all kinds of spectacles. On April 8th millions witnessed a total photo voltaic eclipse. Lots of are going to be actually much less mesmerized when, in the coming times, trillions of cicadas seem in the nation's Midwest and south-east. The flock will be actually abnormally large considering that 2 forms of the pest-- Brood XIII and also Family XIX-- are actually developing at the same time. The last opportunity they showed up together remained in 1803, when Thomas Jefferson was actually president. Why perform the cicadas possess such an uncommon life process?