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🌳 Brood X 第10蟬群
In backyards and forests all across the eastern United States, Brood X is beginning to emerge. With their red eyes and shiny black bodies, the legions of Brood X may seem like some kind of alien invader. But these strange creatures aren’t aliens, and they aren’t invaders either—they’ve been here all along. What are they? Cicadas!
在美國東部的家庭後院和森林，第10蟬群開始現身。有著紅眼睛跟漆黑發亮的身體，第10蟬群軍團就像是某種外星入侵者。不過這些奇怪的生物不是外星來的，也不是入侵者，它們一直都在這裡。它們到底是什麼？牠們是蟬！
There are over 3,000 species of cicadas around the world, but what makes Magicicada—seven closely related species of North American cicada—unique is their 13 to 17 year life cycle, the longest of any cicada. Most other cicada species have life cycles that last just three to five years. Of the 12 broods of 17-year cicadas that can be found in the U.S., Brood X is the largest—both in terms of geographic distribution and population size.
地球上一共有三千多種的蟬，不過這種名為 Magicicada 的物種（是北美蟬中密切相關的七個物種），其獨特之處在於，牠們的生命週期長達13到17年，是所有種類的蟬中生命最長的。其他大多數的蟬物種，其生命週期只能持續3到5年。在美國境內的12個17年蟬群中，就屬第10蟬群規模最大、分布最廣。
Brood X territory covers 15 states, from Illinois in the Midwest to Georgia in the South and New York in the Northeast—with major concentrations in Maryland, Indiana, Delaware, New Jersey and Pennsylvania. But their numbers are even more impressive. An acre of soil—they spend most of their lives underground—can contain over a million cicadas, and a single generation of Brood X may consist of billions and even trillions of the insects!
第10蟬群的分布範圍含括15個州，從美國中西部的伊利諾州，到南部的喬治亞州與東北部的紐約州，主要集中於馬里蘭州、印第安納州、德拉瓦州、新澤西州與賓州。不過牠們的數量更是驚人，牠們多數時間生活在地下，一英畝的土壤可以容納約一百萬隻蟬，而第10蟬群的一代約有數十億甚至數兆隻！
The current generation of Brood X got its start in 2004, back when Facebook was only available to Harvard students. At that time, newly hatched cicada nymphs fell from trees and burrowed underground, where they feed on the sap of tree and grass roots and slowly mature over the next 17 years. Now they’re slowly beginning to emerge from the soil, climb back up into the trees and molt into their adult form. Then they’ll have just a few weeks to sing their high-pitched songs, mate, and lay their eggs before their short adult lives end.
第10蟬群最新的一代始於2004年，當時臉書才剛起步。那年剛孵出的蟬幼蟲從樹上掉下去，鑽到地下，在地底下牠們以樹汁草汁為食，並在接下來的17年裡慢慢成熟。現在正是牠們慢慢地從土壤中冒出、爬回樹上並蛻變為成年型態的時候。接著，牠們只有幾週的時間可以鳴唱高音調的歌曲、進行交配、產卵，然後牠們短暫的成年生活就此結束。
Early European settlers in America called these insects “locusts,” because they reminded them of the swarms of locusts God used to punish the wicked in the Bible. But unlike locusts, which can damage crops and cause famines, cicadas are largely harmless. After emerging, they don’t eat plants like other insects. In fact, they don’t eat anything at all. Some people may find large swarms of cicadas scary, but they’re quite a sight to see! And if you can’t make it to the U.S. this year, don’t worry—Brood X will be back for another visit in 2038.
早期到美國的歐洲移民者稱這些昆蟲為「蝗蟲」，因這群昆蟲讓他們聯想到聖經裡頭上帝用來懲罰作惡之人的蝗蟲群。不過，牠們跟蝗蟲不同，蝗蟲會破壞農作物並導致饑荒，但蟬幾乎可以說是無害的。牠們冒出土壤後，不會像其他昆蟲以植物為食。事實上，牠們根本不吃東西。有人覺得一大群蟬很嚇人，但是這其實是一大奇觀！如果你今年沒辦法到美國去看，請放心，第10蟬群將會在2038年再次到訪。
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