Fruit Flies in the Danger Zone
April 24, 2014
What do fruit flies and fighter jets have in common (besides having wings and being able to fly)? The answer explains why fruit flies are so hard to swat. Scientists from the University of Washington have discovered that, like fighter jets, fruit flies can make lightning-quick banked turns to evade threats.
To make a banked turn, a pilot rotates a plane so its wings go from horizontal to vertical. The pilot then makes the plane veer sharply to the left or right. Banked turns are perhaps more common in action movies than in real-life dogfights (aerial battles), which rarely occur today, but they are an effective way to dodge attacks. Fruit flies do not have fixed wings as airplanes do, but they can rotate themselves in a similar manner, in a tiny fraction of a second. Scientists discovered this ability using high-speed cameras that took 7,500 pictures per second—a necessary technical requirement, because fruit flies flap their wings about 200 times per second. Even at those speeds, the fruit fly’s banking maneuver took researchers by surprise for its swiftness. With just one or two wingbeats, the fruit fly can roll its body’s orientation and bank. The whole process takes about 1/50 of the time it takes to blink. A fruit fly can make a banked turn about five times as fast as a normal turn.
So what’s the best way to swat the pesky creatures? One suggestion is to avoid coming at the fly from the side because the insect will then fly straight away from you, Instead, keep your hand going in the same direction as you swat.
Fruit flies have long been studied in laboratories because they reproduce quickly and are relatively easy to observe. Yet scientists are still not sure how, exactly, the tiny-brained creatures manage such a complex evasive aerial maneuver so quickly in response to a threat. Researchers hoped that further studies of the fruit fly’s nervous system will unlock more of the creature’s secrets.
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