What Happens When a Fly Lands on Your Food?

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iStock

"Waiter, what's this fly doing in my soup?"
"Transmitting bacteria, sir."

This gross response doesn't make a great punchline (nor will it earn anybody a big tip), but it is the truth. But why is that fly just sitting—or swimming—there? And is the soup still safe to eat? If you really want to know, gird yourself and read on.

The common house fly (Musca domestica) has no venom, no stinger, and no fangs. It finds its food in a peaceful way—by rolling around in other animals' waste and garbage. With no teeth, the fly requires a liquid diet. This would be a problem, since a lot of food is solid, but the fly has a disgusting workaround: It spits and pukes on its meal. Compounds in its saliva and bile break down the food, making it as slurpable as a smoothie.

As the fly eats, it's usually also pooping—and if it's female, possibly laying eggs as well. Flies really are an absolute bonanza of disgustingness.

All of this would be gross, but ultimately harmless, if flies only ate soup. But they're opportunists. They eat rotting garbage and they eat animal feces, and in doing so they consume loads of pathogens.

"House flies are the movers of any disgusting pathogenic microorganism you can think of," Jeff Scott, an entomologist at Cornell University, told the Daily Mail. "Anything that comes out of an animal, such as bacteria and viruses, house flies can take from that waste and deposit on your sandwich."

Experts estimate that adult houseflies can transmit more than 100 different diseases and parasites, from Salmonella and tuberculosis to tapeworms.

Does this mean we should immediately throw out any food a fly has touched? Probably.

According to research initiated at Penn State Eberly College of Science and in collaboration with the Nanyang Technological University in Singapore and other international institutions , houseflies tend to harbor pathogens on their legs, meaning even a brief touchdown on your tuna melt could very conceivably transmit any number of worrisome bacteria in an instant. It's better to keep picnic foods sealed until they're needed or to ask for a new dish if your local restaurant has any unsolicited, winged guests lurking around. 

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Why Do Dogs Lick?

iStock/MichaelSvoboda
iStock/MichaelSvoboda

​One of the more slightly annoying things our dogs do (or most adorable, depending on who you ask) involves their tongue obsessively licking every crevice of every spot possible in pretty much the whole world. From our faces to our furniture to themselves, some dogs are absolutely in love with licking anything and everything. Although it can be cute at first, it quickly gets pretty gross. So why do they do it?

According to ​Vetstreet, your pup's incessant licking is mostly their way of trying to show affection. When we pick up our dogs or give them attention, chances are we kiss or pat their heads, along with petting their fur. Their way to show love back to us is by licking.

However, there are other reasons your dog might be obsessively licking—including as a way to get attention. Licking can be a learned behavior for dogs, as they see that when they lick their owner, they get more attention. The behavior can seem like something humans want which, to an extent, it is.

Licking is also a sensory tool, so if your dog is licking random objects or areas of your home, they're probably just exploring. It's easier to get a feel for their surroundings if they can taste everything. But licking objects like your rug or furniture can also be indicative of anxiety or boredom (which can often lead to destructive behavior), and a recent study linked excessive licking of surfaces to certain gastrointestinal disorders.

Another reason for licking is your dog wanting to clean themselves and/or spots around them. They've seen it since they were born; animals lick things ritualistically for cleaning and care. If your dog seems to be obsessed with licking themselves or one particular thing, they probably are. (Yes, dogs can have OCD, too.)

As Vetstreet points out, "excessive" dog licking often only seems excessive to the dog's owner, not the pooch itself. But if it's bothersome enough to you, a trainer can often help curb your dog's enthusiasm for giving wet, sloppy kisses. And while strange behavior is not rare for pets, if your dog's licking seems odd or in any way concerning, there's no harm in taking your pet to the vet to check it out—even if it's just for peace of mind.

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How Are Balloons Chosen for the Macy's Thanksgiving Day Parade?

iStock/RoBeDeRo
iStock/RoBeDeRo

The balloons for this year's Macy’s Thanksgiving Day Parade range from the classics like Charlie Brown to more modern characters who have debuted in the past few years, including The Elf On The Shelf. New to the parade this year are the Teenage Mutant Ninja Turtles. But how does the retail giant choose which characters will appear in the lineup?

Balloon characters are chosen in different ways. For example, in 2011, Macy’s requested B. Boy after parade organizers saw the Tim Burton retrospective at the Museum of Modern Art. (The company had been adding a series of art balloons to the parade lineup since 2005, which it called the Blue Sky Gallery.) When it comes to commercial balloons, though, it appears to be all about the Benjamins.

First-time balloons cost at least $190,000—this covers admission into the parade and the cost of balloon construction. After the initial year, companies can expect to pay Macy’s about $90,000 to get a character into the parade lineup. If you consider that the balloons are out for only an hour or so, that’s about $1500 a minute.

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