8 ms·
Why is it so hard to swat a fly?
- tw1010 9y agoAnd why are flies found in the country significantly harder to swat than those you find in the city?
- grafelic 9y agoIn my experience flies have much harder time avoiding a finger flick.
- roceasta 9y agoYes. Bring the hand close very slowly, forefinger cocked... then....pow. Other techniques I've employed: (1) cling film (saran wrap), (2) detergent spray (slows em down; dispatch after 2-4 rounds), (3) vacuum cleaner nozzle (they hunker down but are sucked in upon take-off)
- pasta 9y agoThe article doesn't mention this but as I understand flies can only see motion. So when you move very slow you can catch them. It doesn't mean that they only see moving objects by the way. In flight they see because everything is moving around them.
- zeotroph 9y agoI thought that most (all?) eyes only see motion, just as you do not feel the weight of your clothes anymore (or the presence/absense of your wallet in your back pocket) after a while. But reading up on microsaccades[1] - tiny involuntary eye movements which I thought fixed that in mammals - that does not seem to be the current understanding anymore. 1: https://en.wikipedia.org/wiki/Microsaccade https://en.wikipedia.org/wiki/Microsaccade
- adekok 9y agoIf you want to catch a stationary fly, it's pretty easy to do so with your bare hands. The key thing to know is that they jump backward before taking flight. Aim for a spot about 1-2" behind the fly, and about 1-2" above the fly. Try to catch it there, and your success percentage will be high.
- thedevil 9y agoI was about to post the same. Last time I used this technique, I hit 3/3.
- anotheryou 9y agoYou have to learn the kind of fly though. Take-off differs between species :)
- oolaf 9y agoI love HN.
- SirFatty 9y agoWhat... is the air-speed velocity of an unladen fly?
- wruza 9y agoThe perspective of cathing a fly that walked on crap five minutes ago disgusts me. I know they cleanse their paws more often than I do mine, but faugh.
- adekok 9y ago1) catch a fly and wash your hands 2) see the fly walk over your food, your face, your kids food... Do you want to touch a "dirty" fly, or eat what the fly has walked on? I'll take #1 any day.
- gbog 9y ago3) Do not care at all, and consider that our bodies are pretty well tuned to handle such thing as a few particles of foreign excrement (or other dirty things). Seriously, we have become irrational animals afraid of everything. (I would wash my hand after splashing a fly if there was a rotten corpse around, though, and would have done even without the fly because my nose would have alerted me of a chemical danger.)
- simpsond 9y agoAnecdote: I find that towel snapping works well.
- i_feel_great 9y agoThree techniques: 1. Move your open hand towards the fly very slowly until you are 5cm (2 in) away then slap. 2. Move both hands slowly towards the fly and "clap" to catch it. 3. Blow gently downwards onto the fly, then slowly increase the force of the blowing. You might then be able to pin its wing to the surface. Yes, I have a lot of time on my hands.
- roceasta 9y ago>Yes, I have a lot of time on my hands. Also a lot of fly goo.
- agumonkey 9y agoProper scientist
- dredmorbius 9y agoSpray fly with water. The spray is likely to hit it. Wet flies don't.
- travmatt 9y agoI've had success with blowing on them before I whack them - I remember hearing they also use changes in the air pressure as a cue to move.
- SomeStupidPoint 9y agoI like the electrified swatters. Mostly because they make an awesome sound. Also, the greatly reduced drag and holes in the surface give fewer warnings to the fly that it's about to be hit, while the use of a tool allows for faster hits. It's really a pretty great invention to kill a lot of flying insects.
- delinka 9y agoWhere’s the video of the killer fly catching a fruit fly? I want to see that.
- zeotroph 9y agoAlso, what is the scientific name of the killer fly? There is no such article on wikipedia. And some more references on how compount eyes see mechanically, as opposed to chemically, would be interesting.
- ximeng 9y agohttps://en.wikipedia.org/wiki/Asilidae https://en.wikipedia.org/wiki/Asilidae maybe this one, although this video explicitly names killer fly: https://www.youtube.com/watch?v=ukiTGsvFP1Y https://www.youtube.com/watch?v=ukiTGsvFP1Y
- softblush 9y agoIt's right in the video embedded in the article. Starts about 55 seconds in.
- delinka 9y agoWas that video available on mobile? I didn't see an embedded video when I read the article.
- fatjokes 9y agoI have perfected this. I can even stop them mid-flight. Spray at it with any liquid (e.g. water, household cleaner). It may take a couple of squirts but it's easy as it doesn't need to be exact. The fly will fall to the ground where you can just squash it with a tissue.
- baybal2 9y agoA more high-tech solution: https://www.aliexpress.com/item/1pcs-Hot-Worldwide-Electric-Insect-Fly-Mosquito-Zapper-Swatter-Killer-3-Net-Racket-Rechargeable/32316697946.html https://www.aliexpress.com/item/1pcs-Hot-Worldwide-Electric-...
- wruza 9y agoBtw, glass cleaner (the one with toxic smell, usually of blue color) is the best tool. Even a light contact with the cloud and it's dead in few seconds. But pay strong attention to not spray it over food, drinks, clothes, fire and your eyes.
- corey_moncure 9y agoAlcohols (including our favorite ethyl alcohol) will kill most if not all arthropods on contact. They absorb it through their exoskeleton and due to their open circulatory system the poison will spread quickly throughout the whole body. The lighter alcohols will evaporate quickly too, making them convenient and effective knockdown agents.
- apl 9y agoAs someone who works in visual neuroscience, this article's a tough read. Lots of statements that are semi-accurate at best. 1) Eyes don't work like cameras; there's no real "exposure" phase as such (even though there's lots of thresholds). So it's misleading to talk about discrete images that we sample at some fixed frequency. Instead, it's much more helpful to think of photoreceptors and subsequent processing stages as continuous band-pass filters. At some point, high frequencies are simply cut off because the electro-chemistry of the cell can't keep up. For us, that cut-off comes earlier than it does for invertebrates. 2) There's no mechanical interaction between light and photoreceptor. Instead, the transduction cascade of the dipteran eye seems to encompass a mechanical (as opposed to biochemical) step. 3) It's pure conjecture to talk about a fly's slowed down "perception" of the world. The reason why they take off before you get to them is much simpler -- there's a highly optimized reflex that connects eye and flight muscles via the giant fiber (a particularly rapid nerve). We have similar responses, like eye lid closing etc. Additionally, their photoreceptors are sensitive and fast. But there's zero evidence that flies have any sense of continuous time that could be faster than ours. Ah, well. The perils of science journalism.
- Retric 9y agoJust to add the distance from a fly's eyes to it's flight muscles is very short which inherently reduces reflex time. They might not view time faster, but they view and react to events much closer to the present.
- taneq 9y agoThanks for the informed opinion. I know way less about animal vision than machine vision but the statement that eyes have a "frame rate" and "send images to the brain a fixed number of times a second" smelled really bad. A maybe-dumb question about point (3) - I've noticed that when I get a blink/flinch response from something (usually some sand or a bug hitting my face when I'm on the bike), it feels like I blink just a split second before the thing hit me. Given that I'm unlikely to have any kind of precognition, do you think this might be related to the blink reflex being 'hard wired' and so my brain gets the "hey, a thing hit your face" signal after the "hey, your eyes just closed" signal? (Alternately, I read something once about our perception of audio being delayed by ~100ms so that it synchs up with our perception of vision, despite our visual processing being slower than audio - maybe the signal that caused the flinch gets 'buffered'?)
- subroutine 9y agoDifferences in visual flicker-fusion rate between species is interesting. But I think it's a bit presumptuous to claim that time drags by 4x more slowly in a fly's reality, and that's why it can usually escape a giant hand falling from the sky. The fly escapes because it's quicker than you. It would probably be just fine if could detect motion at 60 Hz.
- grondilu 9y agoBecause it's much more important for a fly not be swatted than for a large animal to swat it.
- MPSimmons 9y agoOnly partially related to this topic, but is anyone else driven crazy by the Cadillac taillights? I haven't talked to anyone else who is, but I can identify one from a mile away at night. It's like the refresh rate is just low enough that it flashes and it drives me nuts.
- j-conn 9y agoCheck out the "bug-a-salt" salt gun. With good aim it's more effective and fun than a flyswatter. Absurdly, amazon wouldn't ship to California but you can buy from https://bugasalt.com https://bugasalt.com When swatting, I've found they can only fly forward and had good success anticipating that movement. Apparently others in this thread can catch them on the fly's initial backwards jump, which I had never noticed.
- japhyr 9y agoIt's really easy to pick up flies with a hose attachment on a vacuum. Every once in a while we get a number of flies in the house during the summer when the doors and windows are open. They tend to gather in the sides of our windows, looking for a way out. I used to catch them one by one, and then I tried a vacuum. It was easy, once they are aware of the vacuum it's too late to fly away, and they get sucked right up. It's probably not worth while for one or two flies, but if you're going after a few a vacuum can be really effective.
- zomg 9y agoafter watching karate kid, i now catch flies exclusively with chopsticks. i'm 3,285 for 3,285!
- deleted 9y ago[deleted]
- ComputerGuru 9y agoPlease respect HN’s rules for on-topic discussion.
- dagaci 9y agoYou will notice that flies do not generally flee from things swaying (plants branches, curtains) in the wind, if you make a sway movement with your swatting implement the fly will ignore you when your too close for it to escape.
- jwilk 9y ago... when you're too close ...
- praptak 9y agoIt's super easy with an electric fly swatter - it's like a small tennis racket which kills on contact. They might see it with their super fast vision but the racket is just too large for them to avoid m
- jesperlang 9y agoI've found it much easier to try and hit the fly mid air with one open palm, rather than crushing it against a surface. If you hit it, it will be fall to the floor dizzy/stunned. From there just pick it up with a piece of paper.
- roflchoppa 9y agoMan you guys just approaching the problem the wrong way. I’ll tell you how Mike D, a technitian at Apple taught me. You simply wait for the fly to land, and then come at it from behind. The flys launch backwards when they take off, so you can open hand catch them, perform the stun, and get them out of the lab with all your open hardware. I’ll never forget seeing Mike catch that fly.
- lolc 9y agoI keep my hand vertical when approaching the fly and turn it only when accelerating for the swat. That way the approaching hand appears with less dramatic increase in size which allows a quick approach without warning the fly.
- deleted 9y ago[deleted]
- Agathos 9y agoAfter reading these comments, I'm starting to wonder if I'm the only one who owns an old-fashioned flyswatter. With a long, stiff handle and a flick of the wrist, it moves a lot faster than a fly. I've even stunned them by hitting them in mid-air.
- icantrank 9y agonot trying to be that guy, but I swat the fly dead 9/10 times. Mr Miyagi did also train me, but I don't use the chopsticks like my moderated compardre above.
- lenkite 9y agoI really never had a problem catching flies and I don't even think I have fast reactions. You just need to observe their flight silently for a few moments, breathe subtly and make your move suddenly, preferably from the back. They are amazing at avoiding hits from the front. Put yourself in the mindset of a deadly, stalking predator instead of irritated house resident and watch those kill counts stack up.
- NicoJuicy 9y agoWant to kill the fly with your hands, clap above it