SSS 2010-10-15
时间：2019-01-08 作者：英语课 分类：Scientific American(十)月
Many of our medicines originate in plants. But we’re not the only ones who tap into nature.There’s increasing evidence that some animals seek out specific plants for their medicinal qualities. A new study shows that monarch 1 butterflies may be among them.
Monarch butterflies—famous for their U.S.–Mexico migration—feed on dozens of species of milkweed. Some milkweeds have a higher concentration of chemicals called cardenolides, which make the butterflies toxic 2 to predators 3. Research had focused on whether the monarc’s chose different milkweeds to hurt their enemies.
But Emory University’s Jaap de Roode wondered if the choice might be related to a parasite 4 that’s passed from mother to offspring, with fatal results: “What we do find is that the monarchs 5 prefer to lay their eggs on the medicinal species when they are infected. However, when they are not infected with the parasite, they do not prefer this species over this one, they lay their eggs equally between these two species. So somehow they know that they’re infected and they know what to do about it.” The research was published in the journal Ecology Letters.
Co-author Mark Hunter notes that watching animal choices could offer clues about what plants might contain potential medicines for us.
- The monarch's role is purely ceremonial.君主纯粹是个礼仪职位。
- I think myself happier now than the greatest monarch upon earth.我觉得这个时候比世界上什么帝王都快乐。
- The factory had accidentally released a quantity of toxic waste into the sea.这家工厂意外泄漏大量有毒废物到海中。
- There is a risk that toxic chemicals might be blasted into the atmosphere.爆炸后有毒化学物质可能会进入大气层。
- birds and their earthbound predators 鸟和地面上捕食它们的动物
- The eyes of predators are highly sensitive to the slightest movement. 捕食性动物的眼睛能感觉到最细小的动静。 来自《简明英汉词典》
- The lazy man was a parasite on his family.那懒汉是家里的寄生虫。
- I don't want to be a parasite.I must earn my own way in life.我不想做寄生虫，我要自己养活自己。