英语听力精选进阶版 14394（在线收听）

Flies move 'like fighter jets'

Summary

11 April 2014

New research shows that when a threat comes into view, fruit flies make extremely fast turns similar to those made by fighter jets. The study explains why flies are hard to catch, according to the team.

Reporter:

Pallab Ghosh

Report

The research team were astonished by the speed with which fruit flies are able to change direction in mid-flight when faced with a threat.

Like fighter aircraft, they pitch, roll and regain stability, and all in five-thousandths of a second. High speed video shows that this complex and abrupt manoeuvre involves very subtle changes in the insect's wing beat that are barely discernible.

It's a mystery how a creature with a brain the size of a grain of salt is able to process visual information and translate it into precise muscular movements so quickly and precisely. 

But according to the research team, it does help to explain why flies are so difficult to swat.