SSS 2009-01-23(在线收听) |
This is Scientific American's 60-Second Science. I'm Karen Hopkin. This will just take a minute.
As Valentine’s day approaches, remember, it’s the thought that counts. Just ask a decorated cricket. Because according to a study published in the January 21 issue of the journal Biology Letters, the nuptial gift that male crickets use to woo their women is just a handful of amino acids—in a whole lotta water. Many insects use a food offering to win over a potential mate. For crickets, the giftbag serves to distract the female while the actual sperm transfer takes place. As long as she’s busy eating, she won’t reach around and remove that little packet of swimmers. And the longer she feeds, the more sperm will make it through. And, presumably, the more little crickets that male will sire. But the male, of course, wants to get the biggest bang for his buck. So his goal is to minimize what he lays out in his token of appreciation. The solution? The cricket’s gift contains a small sampling of amino acids, mostly nonessential glycine, and 84 percent water. But those amino acids act as an appetite stimulant, which causes the female to spend more time enjoying her nutritionally empty snack. It’s a cheap gift, but it works. Because nothing says “be mine” like a gooey glob of glycine.
Thanks for the minute for Scientific American's 60-Second Science. I'm Karen Hopkin.
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原文地址:http://www.tingroom.com/lesson/sasss/2009/1/98986.html |