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Crazy Facts about Fleas You Won't Believe

Theophanes is a New-England-based blogger, traveler, writer, photographer, sculptor, and lover of cats.

Portrait of a flea through an electron microscope.

Portrait of a flea through an electron microscope.


I know what you're thinking, or rather doing, as you itch your arm staring at the title of this article. It's OK. Fleas are pests, one of mankind's many unwanted companions. Not many people like fleas... and those that do are a little odd. With that being said are fleas really all that bad or is there something we can learn from them?

The Best Jumpers in the World

Fleas have long had the attention of scientists and biologist for one of the things they do very well - jump. They don't just jump, they really put on a spectacular show, with one hop they can jump up to 13 inches. That's more than 130 times their own body height and that's not even the most astounding aspect of this feat. Each jump can subject them to a gravitational force that is 100 times that of normal gravity. 100 G's. Just to put that into perspective our best astronauts can only maintain 5 G's before passing out! Fleas don't just jump once either. They can jump for three days straight before tiring.

The funny thing about all of this is we couldn't figure out how they were doing it. Was it some special property of their knees? Was it their feet? Was it something we haven't thought about yet? Only after the advent of the high speed camera were we able to even properly see a flea launching itself into the air. As it turns out their feet have super traction and their knees don't always hit the ground, so it appears their magic lies in their special feet.Their legs act as levers as they store all the energy needed to hop in their toes. When they finally lift off it's by pushing off on these amazing toes.

You might wonder why we care about knowing these things outside of casual curiosity and the need to win bar bets. Well, it's a good thing to learn because engineers may be able to replicate these feats by building robots someday. Imagine a robot that could hop over any terrain. It could be a great advance in technology.

Flea Jumping Documentary Clip

Giant 0.8 inch fleas harassed dinosaurs in the Jurassic and just like today the females were twice the size as the males.

Giant 0.8 inch fleas harassed dinosaurs in the Jurassic and just like today the females were twice the size as the males.

Dinosaurs had fleas too...

The oldest fossil flea on record came from somewhere between 125-165 million years ago. At the time they did not have the magic feet of today's fleas and couldn't jump, instead they skulked around the ground like mites do today. These prehistoric fleas were super sized just like their prey animals. They could grow up to an eighth of an inch long and had much larger mouthpieces than today's fleas to penetrate the thick hides of dinosaurs.

Flea circuses are real

In the late 1500's watchmaking was an intensive craft that took immense super fine coordination to get all the tiny gears in place. In order to show off their fine motor skills watch makers started leashing fleas... how on earth does this show anything off? Easy, fleas are tiny. First you have to catch one and then you have to take a fine thread and tie it around the fleas' even tinier neck. If you tie it too loose the flea will slip out and get away, if you tie it to tight you end up with a spontaneously headless flea. From here it didn't take long for someone to come up with the idea of making the fleas pull heavy objects around for entertainment. However we may never who did this first or really why... Below is a clip of an actual real-life flea circus. Enjoy.

Enjoy the Spectacle of a Real Flea Circus!

The flea life cycle - not as pretty as a butterfly's but still as impressive.

The flea life cycle - not as pretty as a butterfly's but still as impressive.

Fleas make rabbits look like utterly chaste creatures

Did you know that a newly hatched flea can live up to two weeks without food and its fully mature counterparts can live up to eighteen months? That's quite a feat! In times of plentiful foods fleas generally only live two or three months but they make the best of this. After finding their first host female fleas will only take 1-2 days to start laying eggs. She'll lay 20-50 a day for the rest of her life. These eggs will hatch within 1-10 days depending on humidity and a few other factors and it'll take them 5-11 days to complete their larval stage and enter the pupal stage. They generally hatch out of their cocoons as full adults within two weeks time and will immediately set about finding dinner and a date. Infestations are quick to take over.

After the Black Death claimed millions in Europe these Danse Macabres became very popular in art of the time.

After the Black Death claimed millions in Europe these Danse Macabres became very popular in art of the time.

Fleas are potent biological weapons

The Bubonic Plague is often blamed on rats, but the truth is it wasn't the rats, it was the fleas they carried which were harboring the organism that caused the Black Death. This disease killed up to a third of Europe's entire population, some 20 million people, in the span of five years during the 1300's. If you're wondering what happened to the plague the answer is nothing. In fact two cases a year are averagely reported in the United States, usually from people who own vermin killing cats. How did the death toll go from a third of the population to two cases a year? Geneticists believe people who were strong enough to recover from the disease, or not catch it in the first place, gave their offspring a genetic immunity.

Not to despair though, fleas still spread a lot of diseases like cat scratch fever. Cat scratch fever is something that up to 40% of cats carry at some point in their lives. It is given to them by fleas and transmitted to humans when the cat bites, licks, or scratches a person. People with low immune systems are particularly vulnerable. The cats themselves are put at risk of getting tape worms and catching feline parvovirus and feline leukemia through fleas as well. Dogs also can get tapeworms from fleas as well as at least one other type of worm. They are particularly susceptible to flea allergy dermatitis, basically an allergy to the fleas' saliva which makes them even itchier. Dogs afflicted with this can scratch themselves bald or even tear at their skin. If that's not bad enough they can get Tularemia or Haemobartonellosis which can become serious. Even rabbits are not immune to fleas. Myxomatosis is a serious disease and the scourge of many of a rabbitry. Rabbits who are bitten by infected fleas often die within 48 hours, and most will not make it past two weeks. Recovery is exceedingly rare and the spread of the disease is so rapid that rabbit owners may not have the time to respond correctly. On top of all this when fleas infest any one animal too heavily (especially an older, weak, or young animal) it can overwelm them and literally suck them dry. Anemia will set in and kill these animals if immediate medical attention isn't given. Ask any shelter how many kittens and puppies they lose during the rescue to this and they'll probably have a few stories to tell.

This may be a slight exaggeration of how Diatomaceous Earth really works.

This may be a slight exaggeration of how Diatomaceous Earth really works.

Methods of flea removal..

In the middle ages, if you were filthy rich, there were a few options for getting rid of fleas. One of these options was to put a white bed sheet on your bed, wait for the fleas to hop on, and have your male servants hunt each flea down individually. Or perhaps you'd prefer to drag around a lap dog. Many of these medieval lap dog breeds were created for this purpose only - to lure fleas off their lady owners. Poor people preferred the use of herbs, some like Citronella may have been somewhat effective. Glue traps were also invented in this era just to catch fleas, nothing else.

Today our flea killing methods have changed. Many use harsh pesticides found in flea bombs, flea dips, and things like tea tree oil in the dog shampoo before giving her a bath. It kills fleas dead in a matter of seconds but is not safe for use in cats. Sorry. Fleas are vulnerable to humidity too. If your humidity is below 52% flea eggs will usually not hatch. Spreading salt on the floor may aid in this process as fleas passing by it may have some of their own moisture sucked out by the salt. Diatomaceous Earth is a pretty good natural product too. It is the fossilized remnants of ancient sea creatures and is actually safe to eat according to the FDA. I wouldn't eat it but I have used it. On a microscopic scale it is very sharp and gets into the joints of fleas and other insects and literally tears them to shreds. I have found it very effective.

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Wrapping it up...

In the end fleas have been around far longer than we have and have invented some pretty genius ways of continuously annoying us. We'll probably never be completely rid of fleas but perhaps we can at least learn from them, or try to see the beauty in their overall existence. Science is just catching up with these fast little buggars and who knows what's around the corner.

If you liked this article you may also enjoy others by Theophanes:

The Fascinating Truth about the World's Oldest Pests: Cockroaches

Ants: Their History, Life, and Purpose

The World's Strangest Frogs

The Strangest Cambrian Creatures Ever Discovered

Examples of Insular Dwarfism

Genetic Anomalies in Wild Cats


More from this Author:


Catching Marbles - A New England based travel blog

Tales from the Birdello - For all homesteading and farming matters

Deranged Thoughts from a Cluttered Mind - For funny personal anecdotes


Through the Looking Glass Farm

Typhani Brooks - Artist




Theophanes Avery (author) from New England on August 15, 2014:

Thank you! I know - fleas aren't exactly dinner conversation but it was sure fun to write this one. :)

Carrie Lee Night from Northeast United States on August 15, 2014:

Thank you for writing this interesting hub :). This is a topic I wouldn't normally venture out to read, but I learned do much :). Voted up!

Theophanes Avery (author) from New England on September 14, 2013:

Thanks everyone. You have to love flea circuses, but just the same I'm a big fan of Diatomaceous Earth myself. Use it here all the time, it's great stuff. And thank you so much Barbara Kay, I haven't had a Hub get that particular accolade but I'd be honored if it did. :)

Barbara Badder from USA on September 14, 2013:

This was interesting, but I'll never have an appreciation for these little devils. I hope this make Hub of the Day. It deserves it.

Victoria Lynn from Arkansas, USA on September 14, 2013:

Great info! I'm fighting some fleas this summer. I have some D. Earth to put on the carpets. Will do that this weekend. :)

Mel Flagg COA OSC from Rural Central Florida on September 14, 2013:

What a FANTASTIC hub! I had no idea Flea circuses were actually real. I had to watch that video twice!! My husband says the flea circuses are pay back lol. Voted up and shared! Awesome read!

Theophanes Avery (author) from New England on July 05, 2013:

Why thank you FullofLoveSites and lesibyars! I certainly try. :)

lesliebyars on July 03, 2013:

Great info friend. Voted up, interesting, pinning and the rest.

FullOfLoveSites from United States on June 05, 2013:

Great article and videos -- I like the flea circus! Fleas are of course annoying creatures but you make them more seem interesting. Thanks for posting. :)

Theophanes Avery (author) from New England on March 25, 2013:

Thanks Diana, I am glad you enjoyed it!

Diana L Pierce from Potter County, Pa. on March 25, 2013:

Great hub. I'm sharing this one. Voted up.

Theophanes Avery (author) from New England on March 14, 2013:

Well.... disturb, laugh, they're all good reactions! Thank you for commenting.

John from Irvine, California on March 14, 2013:

This hub disturbed me in more ways than one. I hesitantly commend you.

Theophanes Avery (author) from New England on March 03, 2013:

Glad you enjoyed it Uriel. Not everyone can see the beauty of useless facts about creepy crawlies. ;)

Uriel from Lebanon on March 02, 2013:

I love your hub. I read it yesterday and kept on pausing to reread an interesting section out loud. Mom ended up giving me the -_- face, but all in all , the hub was very educational and well written. Thank you for sharing !!!

Theophanes Avery (author) from New England on March 02, 2013:

Oh, don't I know! They do seem to favor some people. I never had much problems with bugs until I was traveling and met a hoard of chiggers. My travel companion was relatively unfazed but me? Eaten to a bloody pulp!

Kathi Mirto from Fennville on March 02, 2013:

Crazy good stuff . . . learned more about fleas than I ever knew I wanted too! lol, the flip circus clip was hilarious. All I know is that fleas like to bite me and leave huge welts while they leave other's alone! . . . woe is me!

Theophanes Avery (author) from New England on March 02, 2013:

I am happy one of my detours into the strange was that amusing for you. I honestly didn't think anyone would read this one being the main characters are fleas! Thanks for the comments, I love them all. :)

Lisa Stover from Pittsburgh PA on March 01, 2013:

I can certainly say that you caught my attention with this one! Honestly, who would've thought that dinosaurs had fleas. Voted up and useful, great hub!

Martin Kloess from San Francisco on March 01, 2013:

Your title was a bit of an understatement. This was fascinating. Thank you.

Theophanes Avery (author) from New England on March 01, 2013:

Thank you cfin. I try. :)

cfin from The World we live in on March 01, 2013:

What a greatly written and interesting hub.

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