SSS 2008-08-29

（单词翻译）

This is Scientific American's 60-Second Science. I'm Adam Hinterthuer. This will just take a minute.

You’ve probably chased a fly or two around the house this summer. And, chances are, it took a few swings before you brought down the buzzing nuisance. Now a study in the August 28th issue of the journal Current Biology has uncovered just what makes a fly so hard to swat.

Michael Dickinson from the California Institute of Technology used high-speed digital video to record the evasive maneuvers¹ of fruit flies. In the slow-mo instant replay, the flies’ bodies react to a swatter well before their wings carry them to safety. Blessed with nearly 360 degree vision, the fly first gauges² the position of the swatter, then prepares an escape within 200 milliseconds. When approached from the front, for example, a fly shifts its middle legs forward and leans back. If you sneak³ in from the side, the fly leans in the opposite direction.  This positioning then lets the fly spring into a flight pattern that takes it out of the danger zone. So, if you want to get a fly on the first try, Dickinson says to aim at where you think it’s going, not where it is. Or you could always call in a SWAT team.

Thanks for the minute for Scientific American's 60-Second Science. I'm Adam Hinterthuer .