SSS 2012-06-15(在线收听

 Plants that use animals to disperse their seeds can find themselves in a pickle. Their need to make fruit tasty enough to entice the local fauna, but they also need to make sure that their animal assistants don't digest the very seeds they are meant to dispread. In Israel Negev Desert, a plant called Sweet M came up with the distasteful strategy. (Creature) called spiny mice feed on M. They love the fruit, but they hate the seeds. And so they spit them out all over the place, just as the plant planned, not a increate to the study in the journal Current Biology. Sweet M produces little blackberries that helds about twenty seeds at a piece. Inside those seeds, there are enzyme. When a berry chumping mouse crashes the seed, the enzyme freed up to produce compounds that tasts like hot mustard. Hence, better leaving through chemistry. Researchers armed with video cameras observe the mouse spitting the pits like kids eating water melons on a summer day. Nearly three quaters of the (spit-so) seeds landed intact. And they actually germinated twice as fast as the seeds taken directly from the fruit itself. It likes a Dickens book: Great Expectarations.

  原文地址:http://www.tingroom.com/lesson/sasss/2012/6/182374.html