Are Flies Evil or Do They Have an Ulterior Motive for Their Hand-Rubbing Actions?

“Mwahahaha!” That’s the inner dialogue we imagine flies have when we get up close and personal with them thanks to the sinister way they rub their hands. But there’s actually a very scientific explanation for flies’ appearance of world domination.

Summer is the season of unwanted flies, both inside and outside, and we just want to understand these little guys. Are they really trying to take over our homes (and then the world) Little Shop of Horrors-style? Why do flies rub their little hands?

Like most weird things animals do, flies rubbing their hands is just a cleaning method. It’s kind of like how cats lick themselves — it’s super weird and seems unhygienic, but it’s actually just a way to take care of the germs. Basically, flies use their legs and “hands” (sidebar: flies don’t actually have hands) to sense the world around them.

It’s not an exact comparison, but flies can essentially taste using their limbs. But that also makes their limbs a rife breeding ground for germs. Scientist Simon Pollard explained (via The Kid Should See This), “Special sense organs on its feet can tell the fly what type of food it has landed on, and whether it can eat it. It is very important for a fly to keep its feet clean, so it can identify what it has landed on.

“In the world of flies, tiny particles, like pollen grains, dust – which is mostly bits of dead skin, bits of dead insects, etc. can become stuck to the fly’s body, and especially the feet, when the fly is walking around. Flies, by rubbing their legs together can clean off these tiny particles … Flies also clean other parts of their bodies, like their eyes, by brushing over them with their legs.”

Yes, flies rub their hands for cleaning purposes, but they also rub their whole bodies. They rub their heads, their hind legs … well, those are all their body parts. Even though flies are dirty and carry lots of diseases, they do everything they can to stay clean!

Maybe we should be less judgmental of our little gross houseguests next time we see them … they are trying their best!