# Can flies see their feet?

I have a pesky fly that keeps landing on my computer screen. I try wiggling the mouse pointer under him but it doesn't make him fly away. Does he not see the pointer or does he just not care?

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tchitt
Awesome that a topic like this can stay open while the one I made is deleted.

I'm glad I didn't decide to contribute.

Redbelly98
Staff Emeritus
Homework Helper
trib, how about an image of a sugar cube? I'm sure he'll be drawn to that. Once you have its attention, move the sugar over to the side of your monitor. He'll follow it there and stay out of the way!

turbo
Gold Member
An image of some doggy-do might work, too.

trib, how about an image of a sugar cube? I'm sure he'll be drawn to that. Once you have its attention, move the sugar over to the side of your monitor. He'll follow it there and stay out of the way!
Once, while in jail, Amarillo Slim bet the officers on duty that he could train a fly. He asked his guards to bring him two sugar cubes and bet with them on whether he could tell a fly which sugar cube to land on. He won every time. The trick: he would lick one of his finger tips and touch the cube he wanted it to land on with the moist finger to release the scent of the sugar.

BobG
Homework Helper
An image of some doggy-do might work, too.
Once, while in jail, Amarillo Slim bet the officers on duty that he could train a fly. He asked his guards to bring him two sugar cubes and bet with them on whether he could tell a fly which sugar cube to land on. He won every time. The trick: he would lick one of his finger tips and touch the cube he wanted it to land on with the moist finger to release the scent of the sugar.
So what you're saying is that he has to smear some real doggy-do in the corner of the monitor in order for that trick to work.

None the less, the whole problem reminds me of mice and flies:

This is a story about A Fly, a Fish, a Bear A Hunter, a Mouse and a Cat.

There is a moral to this story.....

In the dead of summer a fly was resting among leaves beside a stream.
The hot, dry fly said to no one in particular,
'Gosh... if I go down three inches
I will feel the mist
From the water and I will be refreshed.'

There was a fish in the water thinking,
'Gosh... if that fly goes down three inches, I can eat him.'

There was a bear on the shore thinking,
'Gosh... if that fly goes down three inches
That fish will jump for the fly...
And I will grab the fish!!'

It also happened that a hunter was farther up the bank
Of the lake preparing to eat a cheese sandwich....
'Gosh,' he thought, 'if that fly goes down three inches...
And that fish leaps for it...
That bear will expose himself and grab for the fish.
I'll shoot the bear and have a proper lunch.'

Now, you probably think this is
Enough activity on one river bank,
But I can tell you there's more...

A wee mouse by the hunter's foot was thinking,
'Gosh, if that fly goes down three inches...
And that fish jumps for that fly..
And that bear grabs for that fish..
The dumb hunter will shoot the bear
And drop his cheese sandwich.'

A cat lurking in the bushes took in this scene and thought,
'Gosh... if that fly goes down three inches..
And that fish jumps for that fly
And that bear grabs for that fish
And that hunter shoots that bear..
And that mouse makes off with the cheese sandwich .
Then I can have mouse for lunch.'

The poor fly is finally so hot and so dry that he
Heads down for the cooling mist of the water.
The fish swallows the fly...
The bear grabs the fish..
The hunter shoots the bear..
The mouse grabs the cheese sandwich...
The cat jumps for the mouse..
The mouse ducks...
The cat falls into the water and drowns.

NOW, The Moral Of The Story....

Whenever a fly goes down three inches,
Some pussy's gonna be in serious danger.

That's not how flys eyes work. They see things based on relative motion, aka optic flow.

If you want to kill a fly, the last thing you want to do is swat at it. The flies eyes measure optic flow. If your hand is rushing at it, the fly thinks its flying full speed towards a wall and will fly away. Instead, move your hand s-l-o-w-l-y towards the fly. I can usually get within three inches from it when its sitting there. Then once your 3inches away stop and hold your hand there for a few seconds so there is no motion. Then move your hand quickly and kill it. By then your hand is too close for the fly to react in time.

Kills em every time.

That's not very sanitary.

Use a laser pointer. Focus it on it's eyes and after a few minutes, watch it spin!

I saw a show on PBS about flies once and they had slow motion video of a fly taking off. they showed both voluntary take offs and swatting take offs. When a fly is getting swatted it goes into panic mode and sometimes does back flips or crashes into the floor it is hilarious. Their legs just automatically launch them when you swat at them no matter which direction they are pointed.

Ivan Seeking
Staff Emeritus
Gold Member
My fly story: At one point as a kid I had a praying mantis. Being that I had to catch food for the little beast, I got quite good at catching flies. But my technique improved significantly when I learned from a then gossip story about Howard Hughes that you always swipe at a fly from the rear when trying to catch one. It worked.

Allegedly, Hughes required that all flies be caught, and caught by hand. IIRC, [as the story goes] he even issued an instruction manual to his employees.

Dunno but all but one of my fruit flies are dead! Theres plenty of eggs so I think I'll be ok but I'm not totally sure.

At one time I had a Venus Fly trap. It would not close on a fly. Finally I dropped some raw hamburger into it; it closed then it died??

This sounds like it should have a punch line ?? anyone??

At one time I had a Venus Fly trap. It would not close on a fly. Finally I dropped some raw hamburger into it; it closed then it died??

This sounds like it should have a punch line ?? anyone??
the moral to this story: When someone opens their fly keep the meat out of your mouth.

lisab
Staff Emeritus
Gold Member
Dunno but all but one of my fruit flies are dead! Theres plenty of eggs so I think I'll be ok but I'm not totally sure.
Wow, that must have been one hell of a fly party.

Yeah, they must know how to brew with that yeast that they were supposed to be eating...

Ivan Seeking
Staff Emeritus
Gold Member
At one time I had a Venus Fly trap. It would not close on a fly. Finally I dropped some raw hamburger into it; it closed then it died??

This sounds like it should have a punch line ?? anyone??
Obviously it was a vegetarian.

tchitt
Obviously it was a vegetarian.
Would that make it a cannibal?

BobG
Homework Helper
My fly story: At one point as a kid I had a praying mantis. Being that I had to catch food for the little beast, I got quite good at catching flies. But my technique improved significantly when I learned from a then gossip story about Howard Hughes that you always swipe at a fly from the rear when trying to catch one. It worked.

Allegedly, Hughes required that all flies be caught, and caught by hand. IIRC, [as the story goes] he even issued an instruction manual to his employees.
Yes, the swipe from the rear practically always works. You can then throw them into the wall as hard as you can. They're momentarily stunned so you can do whatever you want with them, but they'll eventually regain conciousness with no noticeable damage.

You can even do this more than once. Wait for them to regain conciousness and throw them into the wall again. I'm not sure how many times you can do this and still have them regain conciousness, but at least 3 or 4 times.

Best bet is to put them in a plastic vial and put them into the freezer. Once they thaw, they'll fly as well as they ever did. Once you've accumulated about a dozen, you superglue them to a paper airplane to provide powered flight.

There is absolutley nothing strange or bizarre about doing this.

I don't want a fly powered airplane. I would like a fly on a leash though. how long of a piece of thread do you think a fly could lift?