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Do Flies Really Throw Up on Your Food When They Land On It? Let's Dive In
https://www.sciencealert.com ^ | NOVEMBER 9, 2021 | RAVINDRA PALAVALLI-NETTIMI & JAMIE THEOBALD

Posted on 11/09/2021 8:19:16 AM PST by Red Badger

A fly regurgitating digestive juices. (Carlos Ruiz/CC BY-ND)

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Imagine you're at a picnic and just about to bite into your sandwich. Suddenly you spot a fly headed your way, homing in on your food with help from its compound eyes and antennae. It manages to escape your swatting, lands on the sandwich and then seems to throw up on it!

It can look kind of gross, but the fly might be just airing out its own digested food, or spitting on yours.

Most of the over 110,000 known fly species have no teeth, so they cannot chew solid food. Their mouthparts are like a spongy straw. Once they land on your food, they need to release digestive juices to liquefy it into a predigested, slurpable soup they can swallow. In short, some flies are on a liquid diet.

To fit more food in their stomachs, some flies try to reduce the liquid in what they have already eaten. They regurgitate food into vomit bubbles to dry it out a bit. Once some water has evaporated they can ingest this more concentrated food.

Human beings don't need to do all this spitting and regurgitating to get nutrients out of our food. But you do produce a digestive juice in your saliva, an enzyme called amylase, which predigests some of the sandwich bread while you chew.

Amylase breaks down starch, which you can't taste, into simple sugars like glucose, which you can taste. That's why bread gets sweeter the longer you chew it.

Did you know flies can taste food without their mouths? As soon as they land, they use receptors on their feet to decide whether they're on something nutritious.

You may have noticed a fly rubbing its legs together, like a hungry customer getting ready to devour a meal. This is called grooming – the fly is essentially cleaning itself, and may also clean the taste sensors on the bristles and fine hair of its feet, to get a better idea of what is in the food it has landed on.

VIDEO AT LINK........................

Should you trash food a fly's landed on? When a fly touches down on your sandwich, that's probably not the only thing it's landed on that day. Flies often sit on gross stuff, like a dumpster or decomposing food, that's full of microbes. The germs can hitch a ride and, if the fly stays put long enough, hop onto your meal.

This is much more dangerous than their saliva because some of the microbes can cause diseases, like cholera and typhoid. But if the fly doesn't stay longer than a few seconds the chances of microbes transferring are low, and your food is probably fine.

To keep insects from landing on your food, you should always cover it. If your house is infested with flies, you can use simple traps to get rid of them. Carnivorous plants can also eat the flies and help control their population.

Are flies good for anything? Spitting on food and spreading diseases sounds disgusting, but flies aren't all bad.

Watch closely the next time you're outside and you might be surprised by how many flies visit flowers to get nectar. They're an important group of pollinators, and many plants need flies to help them reproduce.

Flies are also a good source of food for frogs, lizards, spiders and birds, so they're a valuable part of the ecosystem.

Some flies have medical uses, too. For example, doctors use blow fly maggots – the young, immature form of flies – to remove decomposing tissue in wounds. The maggots release antiviral and antimicrobial juices, and these have helped scientists create new treatments for infections.

More importantly, the fruit flies you may have seen flying around ripe bananas in your kitchen have been invaluable in biological research. Biomedical scientists from all over the world study fruit flies to find causes and cures for diseases and genetic disorders.

And in our lab, we study what the world looks like to insects, and how they use their vision to fly. This knowledge can inspire engineers to build better robots.

So, although it's a nuisance to shoo flies away from your sandwich, maybe you can spare a few bits of your lunch?

Ravindra Palavalli-Nettimi, Postdoctoral Research Associate, Florida International University and Jamie Theobald, Associate Professor of Biological Sciences, Florida International University.


TOPICS: Agriculture; Food; Gardening; Health/Medicine
KEYWORDS: jamietheobald; palavallinettimi
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To: TexasGator

We also have YELLOWFLIES that can leave a large lump in your skin for months........................


21 posted on 11/09/2021 8:55:35 AM PST by Red Badger (Homeless veterans camp in the streets while illegal aliens are put up in hotels.....................)
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To: TexasGator

We also have YELLOWFLIES that can leave a large lump in your skin for months........................


22 posted on 11/09/2021 8:55:41 AM PST by Red Badger (Homeless veterans camp in the streets while illegal aliens are put up in hotels.....................)
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To: TexasGator

https://entnemdept.ufl.edu/creatures/livestock/yellow_fly.htm


23 posted on 11/09/2021 8:56:38 AM PST by Red Badger (Homeless veterans camp in the streets while illegal aliens are put up in hotels.....................)
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To: BenLurkin

So this fly landed on my sandwich...look what it barfed up!


24 posted on 11/09/2021 8:58:32 AM PST by Magnum44 (...against all enemies, foreign and domestic...)
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To: mylife

Ever been bit by a YELLOWFLY?.................

https://entnemdept.ufl.edu/creatures/livestock/yellow_fly.htm


25 posted on 11/09/2021 8:58:32 AM PST by Red Badger (Homeless veterans camp in the streets while illegal aliens are put up in hotels.....................)
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To: Red Badger

Females are the bloodsuckers.


26 posted on 11/09/2021 8:59:14 AM PST by TexasGator (UF)
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To: TexasGator

Always.......................


27 posted on 11/09/2021 8:59:38 AM PST by Red Badger (Homeless veterans camp in the streets while illegal aliens are put up in hotels.....................)
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To: Red Badger

probably


28 posted on 11/09/2021 9:00:36 AM PST by mylife (Joe Biden is like bald tires in the rain, Alec Baldwin with a gun....)
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To: Red Badger

The only time I ever really watched one was years ago when I was eating French toast and had spilled some powdered sugar on the countertop. A fly came along and began to lap it up. It had a tongue like one of those bugs in the Cootie game. I would normally have shooed it away, but it seemed to be enjoying itself so much that I let it be.


29 posted on 11/09/2021 9:01:39 AM PST by Southside_Chicago_Republican (The more I learn about people, the more I like my dog. )
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To: mylife

https://americanceliac.org/yellow-flies-bites-how-to-kill-and-repellants/


30 posted on 11/09/2021 9:05:52 AM PST by Red Badger (Homeless veterans camp in the streets while illegal aliens are put up in hotels.....................)
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To: Red Badger

They are a good source of flyber.


31 posted on 11/09/2021 9:15:03 AM PST by Bob434
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To: Fester Chugabrew

[[I’ve often wondered what the footsteps of spiders and flies would sound like if they were amplified enough. Steady rhythm? 1/8 time? Accents?]]

I’ve a.ways wondered what people who wonder about what flies and spiders sound like walking, think about 😆


32 posted on 11/09/2021 9:17:05 AM PST by Bob434
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To: Bob434

Great taste, less filling.........Kermit...............


33 posted on 11/09/2021 9:17:53 AM PST by Red Badger (Homeless veterans camp in the streets while illegal aliens are put up in hotels.....................)
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To: Bob434
Yule Gibbons said that about pine cones...look where it got him.


34 posted on 11/09/2021 9:18:55 AM PST by Magnum44 (...against all enemies, foreign and domestic...)
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To: Red Badger

We have gorse flies, deer flies too, smaller than horse flies. They are relentless too. They must really drive the animals in the woods bonkers


35 posted on 11/09/2021 9:19:51 AM PST by Bob434
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To: Red Badger

Those look like deer flies, but lighter and yellow. Ours are dark bodies, with multicolored eyes. They are kinda cool looking, the eyes I mean. I got some macro photos of them. But yeah, they hurt like the Dickenson when they bite


36 posted on 11/09/2021 9:22:11 AM PST by Bob434
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To: Red Badger

Lol. On everyone loves Raymond show, Robert dated a woman who ate flies, claiming that “we all come fro. Frogs” it was a pretty funny show


37 posted on 11/09/2021 9:23:37 AM PST by Bob434
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To: BenLurkin
What that fly is thinking...

Help me, help me!!!!

38 posted on 11/09/2021 9:24:49 AM PST by mewzilla (Those aren't masks. They're muzzles. )
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To: Magnum44

Don’t know the fella, where I’d it get him? Emergency surgery for Impacted Colon?


39 posted on 11/09/2021 9:26:18 AM PST by Bob434
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To: Bob434

Sheesh- I meant “where did it get him?” Stupic autocorrect


40 posted on 11/09/2021 9:27:10 AM PST by Bob434
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