【英语时差8,16】植物怎样自我防卫（下）

Even more sophisticated is the strategy used by a type of wild potato to defend itself against aphids. The plant manufactures the active ingredient of the so-called aphid alarm pheromone, a chemical that an aphid under attack releases into the air to warn other aphids of danger. Aphids run away from the wild potato plant’s chemical signal as if it were a danger signal from an aphid. There are a couple of general lessons to be drawn¹ from the ecologists’ ever-growing collection of plant chemical-defense stories. One lesson is the importance of preserving the great natural diversity of plants, because we can learn so much chemistry from them. Also, the very specific nature of the chemical weapons used by many plants gives us hope that we humans can develop pesticides that will hurt only their intended targets.

1 drawn   

v.拖，拉，拔出；adj.憔悴的，紧张的

参考例句：

• All the characters in the story are drawn from life.故事中的所有人物都取材于生活。
• Her gaze was drawn irresistibly to the scene outside.她的目光禁不住被外面的风景所吸引。