Why Is It so Hard to Swat a Fly?

Flies are evasive buzzing machines that make it nearly impossible to swat. Luckily, science has some explanation to help you predict their next move.

Hosted by: Stefan Chin

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[ruawhitepaw]

Of course, every time you catch a fly, you just help evolution produce even better flies.

[irvingchies]

To swat a fly you need to know their IP address first, then find out their actual physical address, which is not always their actual address since ISPs don't always have it on hand

[mannyfernandez]

Now how about the one in which the fly can enter through a milimetric hole, yet can’t fly out of a semi sized fully opened window

[gendragongfly]

They forgot to mention flies and most other small flying insects are so light the wind created by you swinging that magazine at them is enough to blow them out of the way before the magazine can actually squash them. Which is why fly swatters have holes and why a magazine or newspaper works better when rolled up. I also think curved mirrored surfaces might confuse them because they are easier to hit whilst in flight if you use a spoon.

[sizanogreen]

The trick lies in moving slowly. Catching them with a glass this way is relatively easy, depending of course where they have decided to plant their six legs upon.

[ScrapPalletMan]

My gross party trick is catching flies: I aim 3in above the fly and swoop in snapping my hand closed like a Venus flytrap. No pun intended LOL

[johnnyxxxv]

As a kid, I used to swat flies rather enthusiastically, I remember breaking more fly swatters than it should be normal. On top of that, often I would see flies flee the moment I grabbed the swatter, before even coming near one.

[FarhanAmin]

Mosquitoes causing me more distress rn :'( They have clearly evolved to get tougher. They occasionally survive getting smacked now and have also been surviving in the cold North Indian winter rn.

I've developed a technique to hold flies in the fly with my hand, with an accuracy of about 60/70%. You basically need to let the fly land somewhere, get close enough (considering your own agility and biomechanics) and swing your hand as fast as you can, not where the fly is, but where you predict it will be by the time your hand arrives to that area. With practice you learn better to predict their movements, they are quite predictable and they don't change the evasive move once they chose it.

[fakjbf]

By far the easiest method is to simply wait for them to land on a window, then you can easily just pick them up with two fingers. And make sure throw them outside so they reproduce and continue making stupid flies.

[wmdkitty]

I'd like to know how a creature that can find it's way in through a half-inch gap manages to miss a wide-open door.

[FoxFireNaruto]

My dad taught me a trick for getting them with a vacuum. The key is to move slowly, they mostly stay still and try to adjust to the suction being brought down on them until they can't hold on anymore and get sucked up. We were very successful fly hunters in my house.

[Dogtroll]

Actually I've figured out a way to get around this, you just keep swatting at them in their general direction without trying to hit them. If they try to land swat at them again. If you keep this up they will quickly just burnout and literally fall out of the sky. This is an especially good strategy if you're dealing with a lot of flies, say if someone leaves the door open or if you're in a room with a lot of breakable items.

[levibruner]

As a teen I used airborne flies as punching targets because they were hard to hit lol. Wonder if the neighbors ever saw me and thought to themselves "wtf is he randomly punching the air for?" 😂

[ianmacfarlane]

I was always told that as well as being astonishingly quick, flies take off backwards, (in reverse) so you can use that to your advantage by coming in with the swatter from that direction - it seems to work, but they're so quick that the success rate is never going to be high.

[jrbird]

Another important thing about killing flies is that they jump straight up if they are on a flat surface before taking off in either direction so if you clap your hands together about 2 inches above the fly you are almost guaranteed to get it first try. I learned that little physics lesson in band class because they were pumping the septic tank one day during school and there were 100s of flies that decided to make their way into our classroom. My instructor told us about it and we had a contest to see who could kill the most flies for an extra 100 to average into our final grade where everyone else that participated only got an extra 50 points. I killed 49 flies in about an hour. The winner got like 63. It was a tough competition. lol

[Patmccalk]

The other alternative, instead of using a flyswatter, catch them by hand simply by aiming and swiping your hand about 4-6” above them, they take off into your hand 90% of the time

[llantup]

The trick is to have your swatter move towards the fly on a surface v-e-r-y slowly until you're within about 4-6 inches; then switch to as fast as you can go to hit them. You'll get them about 90% of the time this way.

[falchion]

I use a bug zapping flyswatter that is the size of a tennis racket. You get them in mid-flight and fry them.

[GthCrayon]

I usually snag them out of the air by snatching at them from underneath. I'm typically more successful if it's indoors in a reasonably well lit area with light colored walls -especially if it's a cooler temperature to slow them down a few ticks.

Didn't know that being able to do so was particularly strange until I worked at a restaurant and caught one in front of several coworkers, they didn't believe me until they saw it wash out of my hand and down the nearby sink.