.TYPE IS ACTUALLY TREATING Americans to all type of spectacles. On April 8th millions watched an overall photo voltaic eclipse. Many will be less knocked out when, in the coming days, trillions of cicadas appear in the nation's Midwest and south-east. The throng will certainly be actually extraordinarily huge because 2 kinds of the insect-- Brood XIII and Brood XIX-- are actually arising simultaneously. The final time they appeared at the same time was in 1803, when Thomas Jefferson was president. Why carry out the cicadas have such an uncommon life cycle?