The fly aerates its digested food, and fortunately humans do not need this to get the nutrients from the food
Imagine that you are on a picnic and about to nibble on a sandwich, and suddenly you notice a fly heading towards your sandwich, and it chases your food with the help of its compound eyes and antennae, and when you try to chase it and kill it, it runs away from you, and eventually lands on the sandwich, and then it seems to you that it is vomiting in it!
Why do flies vomit in our food?
Postdoctoral researcher Ravindra Palavalli Netimi and Associate Professor of Biological Sciences Jimmy Theobald at Florida International University answered this question, and others in an article published on the website. “The Conversation”.
The researchers pointed out that this recurring stereotype, which seems somewhat disgusting, and shows the form of human suffering with flies, is only the only way for flies to contain more food in its stomach, as the flies try to reduce fluids in the food that they have already eaten, and this is done by diverting Food into bubbles of vomit to dry it out a bit, and once some of the water evaporates it can eat that more concentrated food.
Fortunately, we humans do not need that.
So the fly is just aerating its digested food, and fortunately humans don’t need to do all that spitting and vomiting to get the nutrients from the food.
On the other hand, we produce digestive juice in our saliva, an enzyme called amylase, which pre-digests the bread as it is chewed. Amylase breaks down starch, which we can’t taste, into simple sugars like glucose that we can taste, which is why bread gets sweeter the longer you chew it.
Tasting food without a mouth
But did you know that flies can taste food without a mouth? Once they land on food, the flies use the receptors on their feet to decide whether to eat something nutritious.
And you may have noticed that a fly rubs its legs together, like a hungry human getting ready for a meal. This is called grooming. The fly is essentially grooming itself, and it may also groom its taste sensors on the whiskers and fine hairs of its feet, to get a better idea of what’s in the food it has landed on.
Are flies good for anything?
Spitting in food and spreading disease is disgusting, but flies aren’t all bad.
The next time you’re outside, keep a close eye on it, and you might be surprised how many flies visit the flowers for nectar. They are 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 are an important part of the feeding cycle within the food web and ecosystem.
Some flies also have medicinal uses. For example, doctors use blowfly larvae – the small, immature form of flies – to remove decaying tissue in wounds. The larvae release antiviral and antimicrobial juices, which has helped scientists devise new treatments for the infection.
Most importantly, the fruit flies you’ve probably seen flying around ripe bananas in your kitchen are invaluable to genetics, science, and biological research. Geneticists, biomedical and other scientists from around the world study fruit flies to find causes and treatments for diseases and genetic disorders.
Scientists are also studying what the world looks like for flies, and how they can fly and land, and this knowledge could inspire engineers to build better robots.
When a fly touches your sandwich, it probably isn’t the only thing you’ve fallen for that day. Flies often land on dangerous objects, such as garbage or decaying food that is full of microbes, and germs can transfer to your meal if the fly stays on the food long enough.
So, although it’s annoying to get the flies off the sandwich, you can probably remove a little flies from your lunch, because this is much more dangerous than their saliva, as some microbes transmitted by flies can cause serious diseases such as cholera and typhoid. But if the fly doesn’t stay longer than a few seconds, the chances of microbe transmission will be low, and your food may be fine.
To prevent insects from landing on your food, you should always cover it. And if your house is infested with flies, you can use simple traps to get rid of it, and some carnivorous plants can also be used, which eat flies and help control their numbers.