Placeholder Image

字幕表 動画を再生する

  • Locusts are grasshoppers - with unusual superpowers.  When triggered by overcrowding they literally

  • transform themselves - changing from green to brown, eating more, getting muscular, mating

  • more, and congregating in crowds. Then, their shy alteregos forgotten, they swarm across

  • the landscape, searching for food, colonizing and recolonizing breeding grounds, and being

  • a general nuisance. There are about a dozen locust species on

  • Earth, and only one has been found in North America: the Rocky Mountain locust, which

  • devastated crops across the Great Plains from 1850 to 1880. The fact that the locusts preferred

  • cultivated crops to prairie grasses ensured that their massive swarms caught the attention

  • of white settlers... though really, the locusts would have been hard to miss.

  • One observer in Nebraska in 1875 watched a mile-high stream of locusts pass overhead

  • for 5 days straight.  Together with telegraphed reports from neighboring towns, he estimated

  • the swarm to be 110 miles wide and 1,800 miles long, roughly twice the size of Colorado.

  • During the biggest outbreaks, locusts consumed all crops in their path, as well as, reportedly,

  • fence posts, leather, and the wool off of sheep. They were such a challenge to the settlement

  • of the western US and Canada that bounty hunters were paid as much as $100 per bushel of dead

  • grasshoppers, and settlers dynamited their breeding grounds.

  • While these methods may have been more satisfying than successful, ultimately the settlers did

  • end up controlling the Rocky Mountain Locusts. In fact, they made them go extinct. By accident.

  • Locusts, like settlers, need to eat AND reproduce. And after outbreaks, locust populations typically

  • retreated back to their permanent breeding grounds in the valleys of the northern Rockies

  • to lay their eggs.

  • However, because these river bottomlands were fertile and had plenty of water, they were

  • also prime locations for pioneer farms and ranches. It turns out that plows, livestock

  • and irrigation excel at destroying locust eggs and crucial locust nymph habitat.

  • By the 1890s, swarming white settlers had covered so much western river bottomland that

  • the locusts weren't able to attain the numbers or density needed to transform into their

  • buff alteregos, and they never swarmed again. The disappearance of these super bugs less

  • than 30 years after they nearly ate agriculture off the Great Plains, is most likely the only

  • extinction of a pest species in the history of agriculture. Because, it turns out, agriculture

  • was their kryptonite.

Locusts are grasshoppers - with unusual superpowers.  When triggered by overcrowding they literally


動画の操作 ここで「動画」の調整と「字幕」の表示を設定することができます

C1 上級

北アメリカの大イナゴ疫病 (The Great North American Locust Plague)

  • 366 11
    Bing-Je に公開 2021 年 01 月 14 日