15 June 2023
Now that it’s insect season we’re back to swatting flies, but are we successful? Mostly not. Flies are masters at avoiding swats for a couple of reasons.
First, they have much faster perception and reaction times than we do. Back in 2008 researchers at Caltech used high speed, high definition video to record the movements of fruit flies avoiding a swat threat. Amazingly, flies can react to an approaching swatter within 100 milliseconds.
Second, the flies’ middle legs are key to their escape. When a fly sees a threat it re-positions its body, sets its long middle legs in the right location, and pushes off from them.
The photo series below from the Caltech study shows a fruit fly perceiving a threat from the front (right side of photos) with red dots indicating the original location of the fly’s middle legs. At 215 milliseconds the fly has its middle legs in launch position. When it jumps at 287 milliseconds (the last possible moment) it’s using its middle legs.
This video shows the experiment in action.
Fly science hasn’t changed that much since the first discovery 15 years ago but the explanation of fly reaction time has gotten better as shown in this video.
We humans move, see, and think slowly compared to a fly but if we can anticipate where the fly will jump and aim for that spot we stand a chance of nabbing it.
Plan ahead to swat a fly.
(photo credits and links are in the captions)
I use a salt gun. Works great.
So cool. Interesting videos. Always wondered why and how I kept missing those pesky fruit flies, especially since they’re so tiny. Thanks for this information.