1 00:00:01,920 --> 00:00:06,360 Speaker 1: Welcome to brain Stuff, a production of iHeart Radio, Hey 2 00:00:06,360 --> 00:00:09,879 Speaker 1: brain Stuff Lawn bold bomb here in May or April 3 00:00:09,960 --> 00:00:12,920 Speaker 1: of this year. One of the largest broods of seventeen 4 00:00:13,000 --> 00:00:16,480 Speaker 1: year Cicadas brewed ten written with the Roman numeral X, 5 00:00:16,840 --> 00:00:19,959 Speaker 1: is going to emerge from its underground layers across the 6 00:00:19,960 --> 00:00:23,080 Speaker 1: eastern United States, from New York down to Georgia and 7 00:00:23,120 --> 00:00:28,080 Speaker 1: west out to Illinois. These are periodical cicadas, insects measuring 8 00:00:28,120 --> 00:00:30,720 Speaker 1: about one and a half inches or four centimeters in length, 9 00:00:30,880 --> 00:00:34,400 Speaker 1: with a red orange hue and protruding red eyes. This 10 00:00:34,560 --> 00:00:38,000 Speaker 1: coloring is an easy way to identify periodical cicadas from 11 00:00:38,000 --> 00:00:42,000 Speaker 1: other species, including the more common dog day cicadas, which 12 00:00:42,040 --> 00:00:44,280 Speaker 1: appear every year at the end of summer and have 13 00:00:44,520 --> 00:00:49,920 Speaker 1: green tinged wings. Periodical cicadas make a rare appearance, relegated 14 00:00:49,960 --> 00:00:53,280 Speaker 1: only to the regions east of the United States Great Plains, 15 00:00:53,520 --> 00:00:57,200 Speaker 1: and nowhere else in the world. In eighteen nine, three 16 00:00:57,280 --> 00:01:02,280 Speaker 1: observers began organizing periodical cicada as into broods. This makes 17 00:01:02,320 --> 00:01:06,720 Speaker 1: it easier to track the insects infrequent arrivals. Each brood 18 00:01:06,760 --> 00:01:09,800 Speaker 1: includes different species of cicadas that emerge together in a 19 00:01:09,840 --> 00:01:13,480 Speaker 1: collective and noisy bid to find suitable mates. There are 20 00:01:13,520 --> 00:01:16,520 Speaker 1: twelve broods of seventeen year cicadas and three broods of 21 00:01:16,560 --> 00:01:19,760 Speaker 1: thirteen year cicadas, which are more prevalent in the southeastern 22 00:01:19,800 --> 00:01:23,120 Speaker 1: part of the United States. Each brood operates on a 23 00:01:23,120 --> 00:01:25,920 Speaker 1: different schedule, which means you don't have to wait thirteen 24 00:01:26,040 --> 00:01:29,760 Speaker 1: or seventeen years to witness the insects next in mass eruption. 25 00:01:30,319 --> 00:01:33,480 Speaker 1: After this year's brewed ten appearance, will get broods thirteen 26 00:01:33,520 --> 00:01:40,360 Speaker 1: and nineteen four and brewed fourteen in. The sudden appearance 27 00:01:40,400 --> 00:01:44,160 Speaker 1: of seventeen year cicadas is one of nature's most spectacular events, 28 00:01:44,200 --> 00:01:47,120 Speaker 1: a phenomenon that perhaps led to the fanciful naming of 29 00:01:47,200 --> 00:01:53,400 Speaker 1: the periodical cicadas genus classification magic Cicada. For centuries, periodical 30 00:01:53,440 --> 00:01:58,320 Speaker 1: cicadas have fascinated scientists and casual observers alike. Millions of 31 00:01:58,320 --> 00:02:01,640 Speaker 1: cicadas may emerge in a single night after spending seventeen 32 00:02:01,720 --> 00:02:05,520 Speaker 1: or thirteen years living underground, feeding off of nutrients sucked 33 00:02:05,520 --> 00:02:08,480 Speaker 1: from the roots of trees and other plants. It's this 34 00:02:08,639 --> 00:02:12,160 Speaker 1: lengthy childhood that serves as an important distinction that enables 35 00:02:12,200 --> 00:02:14,720 Speaker 1: them to have the longest lifespan of any insect in 36 00:02:14,760 --> 00:02:19,600 Speaker 1: North America, seventeen year. Cicadas spend the earliest months of 37 00:02:19,639 --> 00:02:23,320 Speaker 1: their final year burrowing towards the soil's surface. When the 38 00:02:23,320 --> 00:02:26,760 Speaker 1: soil temperature rises above sixty four degrees fahrenheit or about 39 00:02:26,760 --> 00:02:30,520 Speaker 1: eighteen degrees celsius, the cicada nymphs venture out of the soil. 40 00:02:31,080 --> 00:02:33,600 Speaker 1: Their population may number a million or more in a 41 00:02:33,680 --> 00:02:36,320 Speaker 1: space smaller than an acre less than half a hector, 42 00:02:36,600 --> 00:02:40,680 Speaker 1: which helps survival rates. Animals ranging from spiders and birds 43 00:02:40,680 --> 00:02:44,240 Speaker 1: to dogs and snakes find the lumbering cicada's easy prey, 44 00:02:44,639 --> 00:02:46,840 Speaker 1: but will eat their fill long before they put a 45 00:02:46,880 --> 00:02:51,639 Speaker 1: dent in the population. The then flightless young cicada's journey 46 00:02:51,720 --> 00:02:54,400 Speaker 1: upward at sunset, crawling a foot or more up any 47 00:02:54,440 --> 00:02:58,239 Speaker 1: nearby vertical surface tree trunks, weeds, woody shrubs, homes, or 48 00:02:58,280 --> 00:03:02,800 Speaker 1: outbuildings to begin the next phase of life. Overnight, they'll 49 00:03:02,800 --> 00:03:07,080 Speaker 1: shed their nymphul skins a much like the fictional Incredible Hulk. 50 00:03:07,240 --> 00:03:10,520 Speaker 1: The cicadas will split their shell like clothing to unleash 51 00:03:10,680 --> 00:03:14,040 Speaker 1: larger bodies, and as they emerge through the tops of 52 00:03:14,080 --> 00:03:17,280 Speaker 1: their shells, the cicadas will unfurl their wings for the 53 00:03:17,320 --> 00:03:22,200 Speaker 1: first time. Now the cicada is an adult, soft, ashen 54 00:03:22,280 --> 00:03:25,760 Speaker 1: and vulnerable, waiting for its exoskeleton to harden and darken 55 00:03:25,880 --> 00:03:29,240 Speaker 1: in color. It will leave its crunchy larval casing behind, 56 00:03:29,960 --> 00:03:32,840 Speaker 1: still clinging to the cicada's first above ground resting place. 57 00:03:32,960 --> 00:03:35,520 Speaker 1: The casing will be an empty and forgotten outline of 58 00:03:35,560 --> 00:03:40,400 Speaker 1: the creature at once held. Not all cicadas appear on 59 00:03:40,520 --> 00:03:44,480 Speaker 1: a strict schedule, though there are also some known as stragglers, 60 00:03:44,520 --> 00:03:47,160 Speaker 1: that appear a year later or earlier than the rest 61 00:03:47,160 --> 00:03:49,960 Speaker 1: of their brood. One year early or one year late 62 00:03:50,080 --> 00:03:52,760 Speaker 1: is the most common time frame for stragglers, but this 63 00:03:52,800 --> 00:03:55,520 Speaker 1: isn't always the case either. In the year two thousand, 64 00:03:55,560 --> 00:03:59,320 Speaker 1: for example, many brewd ten cicadas appeared four years earlier 65 00:03:59,320 --> 00:04:03,320 Speaker 1: than expected. It Some observers theorize that unseasonably warm weather 66 00:04:03,480 --> 00:04:07,080 Speaker 1: may cause some stragglers to emerge early. Others suggest delayed 67 00:04:07,120 --> 00:04:12,040 Speaker 1: development may cause some stragglers to arrive late. Scientists aren't 68 00:04:12,080 --> 00:04:16,040 Speaker 1: exactly sure how cicadas no seventeen years or thirteen years 69 00:04:16,080 --> 00:04:18,600 Speaker 1: have passed in the first place. They think it might 70 00:04:18,640 --> 00:04:21,320 Speaker 1: have something to do with some property in the fluid 71 00:04:21,360 --> 00:04:23,440 Speaker 1: that they suck out of tree roots for nourishment when 72 00:04:23,440 --> 00:04:28,479 Speaker 1: they're underground, something that reflects the yearly cycle of the tree. Perhaps, 73 00:04:28,600 --> 00:04:32,040 Speaker 1: if whatever this chemical signal is is weaker for insects 74 00:04:32,120 --> 00:04:35,200 Speaker 1: under one type of tree versus another, that causes the 75 00:04:35,400 --> 00:04:40,920 Speaker 1: off schedule appearances. Interestingly, the prime number appearances are thought 76 00:04:40,960 --> 00:04:44,040 Speaker 1: to help with survival. Since the cicadas are not on 77 00:04:44,160 --> 00:04:46,760 Speaker 1: the same two year or five year cycle as most 78 00:04:46,800 --> 00:04:49,960 Speaker 1: of their predators, the predators don't become dependent on them 79 00:04:49,960 --> 00:04:53,520 Speaker 1: for food. Stragglers who missed the big party are more 80 00:04:53,600 --> 00:04:57,960 Speaker 1: likely to be eaten off. Periodical cicadas, whether they're a 81 00:04:58,000 --> 00:05:01,120 Speaker 1: thirteen year or seventeen year species, will live for just 82 00:05:01,240 --> 00:05:04,080 Speaker 1: three or four weeks above ground, only long enough to 83 00:05:04,120 --> 00:05:07,040 Speaker 1: mate and, in the case of female cicadas, deposit eggs. 84 00:05:07,520 --> 00:05:10,160 Speaker 1: This mate then die cycle is pretty common in the 85 00:05:10,160 --> 00:05:14,159 Speaker 1: insect world. Male cicadas attempt to attract females with a 86 00:05:14,200 --> 00:05:17,480 Speaker 1: loud buzzing that seems to undulate up and down between 87 00:05:17,680 --> 00:05:23,640 Speaker 1: two distinct notes. Although each species of periodical cicada has 88 00:05:23,680 --> 00:05:27,440 Speaker 1: its own song, the response of female cicadas varies little 89 00:05:28,000 --> 00:05:31,839 Speaker 1: exactly one third of one second after the male's song ceases. 90 00:05:32,080 --> 00:05:34,760 Speaker 1: A female responds with a click of her wings, but 91 00:05:35,000 --> 00:05:37,919 Speaker 1: only if she wants him to make further advances. The 92 00:05:37,960 --> 00:05:41,040 Speaker 1: male counters with the same call, hoping to hear another 93 00:05:41,080 --> 00:05:44,479 Speaker 1: wing click. If he does, he makes two particular sounds 94 00:05:44,520 --> 00:05:47,679 Speaker 1: in quick succession, awaits for a third wing click, and 95 00:05:47,720 --> 00:05:51,120 Speaker 1: then it's on. Within about ten days, the female will 96 00:05:51,160 --> 00:05:54,520 Speaker 1: deposit some four hundred eggs in small twigs and branches 97 00:05:54,560 --> 00:05:57,359 Speaker 1: of nearby trees and shrubs, but choosing from among the 98 00:05:57,440 --> 00:05:59,880 Speaker 1: eighty or so species that they prefer to use as 99 00:05:59,880 --> 00:06:03,920 Speaker 1: an nurseries. The females have protruding needle like devices at 100 00:06:03,920 --> 00:06:06,400 Speaker 1: the end of their abdomens, which are used to create 101 00:06:06,440 --> 00:06:09,960 Speaker 1: an egg cradle in the wood. Female cicadas may repeat 102 00:06:10,040 --> 00:06:14,640 Speaker 1: the egg laying process dozens of times. In about six weeks, 103 00:06:14,760 --> 00:06:17,680 Speaker 1: white nymphs the size of ants will emerge from the eggs, 104 00:06:17,839 --> 00:06:20,280 Speaker 1: drop to the ground and work their way into the soil. 105 00:06:20,960 --> 00:06:24,000 Speaker 1: Like their parents, they'll spend the next thirteen or seventeen 106 00:06:24,080 --> 00:06:29,120 Speaker 1: years feeding on fluid found in plant roots. Although cicada's 107 00:06:29,200 --> 00:06:33,080 Speaker 1: root feeding is considered harmless, damage caused by female cicadas 108 00:06:33,120 --> 00:06:35,839 Speaker 1: burrowing into trees and shrubs to deposit eggs can be 109 00:06:35,920 --> 00:06:39,560 Speaker 1: significant twigs may break off, which can create production issues 110 00:06:39,600 --> 00:06:43,080 Speaker 1: for fruit and nut orchards, and some caretakers cover small 111 00:06:43,120 --> 00:06:46,360 Speaker 1: trees with mesh cloth to prevent access to bark. Others 112 00:06:46,360 --> 00:06:49,719 Speaker 1: apply in secticides before egg laying occurs, or simply opt 113 00:06:49,760 --> 00:06:54,320 Speaker 1: to wait out the cicada's limited lifespan. However, aside from this, 114 00:06:54,440 --> 00:06:57,960 Speaker 1: these insects are generally harmless to plants and are harmless 115 00:06:57,960 --> 00:07:00,320 Speaker 1: to people, so there's no need to panic if one 116 00:07:00,400 --> 00:07:04,000 Speaker 1: lands on you. And what do you believe that cicada's 117 00:07:04,080 --> 00:07:08,000 Speaker 1: make tasty high protein snacks? Apparently they taste like asparagus 118 00:07:08,040 --> 00:07:10,880 Speaker 1: thanks to their plant based diets. The best ones to 119 00:07:10,960 --> 00:07:13,200 Speaker 1: eat are those still in the nymph stage that don't 120 00:07:13,240 --> 00:07:15,840 Speaker 1: have their hard outer shells yet. You can deep fry 121 00:07:15,920 --> 00:07:23,760 Speaker 1: them and serve them with spicy sauce. Today's episode is 122 00:07:23,800 --> 00:07:26,640 Speaker 1: based on the article why do seventeen years cicadas come 123 00:07:26,680 --> 00:07:29,960 Speaker 1: out more often than every seventeen years? On how Stuffworks 124 00:07:29,960 --> 00:07:33,520 Speaker 1: dot Com? Written by Lori Elda. Brain Stuff is production 125 00:07:33,520 --> 00:07:35,600 Speaker 1: of I heart Radio in partnership with how stuff works 126 00:07:35,600 --> 00:07:38,280 Speaker 1: dot Com and is produced by Tyler Clay. For more 127 00:07:38,280 --> 00:07:40,800 Speaker 1: podcasts my heart Radio, visit the i heart Radio app 128 00:07:40,880 --> 00:07:43,520 Speaker 1: Apple podcasts, or wherever you listen to your favorite shows.