# Do fleas explode at high altitude? **URL:** \ **Category:** Factual Questions\ **Created:** [July 1, 2002, 7:18pm UTC](https://boards.straightdope.com/t/do-fleas-explode-at-high-altitude/116884 "2002-07-01T19:18:18Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![DarrenS](https://avatars.discourse-cdn.com/v4/letter/d/977dab/32.png) [@DarrenS](https://boards.straightdope.com/u/DarrenS)\ **Post date:** [July 1, 2002, 7:18pm UTC](https://boards.straightdope.com/t/do-fleas-explode-at-high-altitude/116884/1 "2002-07-01T19:18:18Z")
We were having one of those “bbq and beer” discussions this weekend, and someone claimed that dogs don’t get fleas in Denver because of the altitude - she went so far as to claim that fleas _explode_ at high altitudes. Now, to me this sounds like a typical urban legend, but I looked on Snopes, [TruthOrFiction.com](http://TruthOrFiction.com), the archives of the SD and in Google. The only thing I came up with was an anecdotal reference to the alleged phenomenon - nothing scientific. So…can any of you debunk or prove the veracity of this? (Please, only scientific, verifiable evidence - things like “uncle George said it’s true so it must be because he has a PhD” don’t help.) ---
**Author:** ![Kamandi](https://avatars.discourse-cdn.com/v4/letter/k/5daacb/32.png) [@Kamandi](https://boards.straightdope.com/u/Kamandi)\ **Post date:** [July 1, 2002, 9:26pm UTC](https://boards.straightdope.com/t/do-fleas-explode-at-high-altitude/116884/2 "2002-07-01T21:26:01Z")
I assume that when you say fleas explode at high altitude, you mean that if a flea were taken from sea level to Denver, the air trapped in its body cavity would burst out under the reduced atmospheric pressure. I don’t buy it. Why would fleas be built without an ability to equalise the air pressure in their bodies? In any case, why couldn’t fleas migrate uphill very slowly, over generations? This would eliminate the pressure differential problem and allow them to infiltrate higher altitude environments. If there are no fleas in Denver (do you have any proof of that assertion?), there could be any number of other explanations. Perhaps it’s too dry there. Or some other local parasite has outcompeted them. Or some critter finds fleas too delicious and eats them all before they can establish a foothold. Or local pesticide use has wiped them all out. ---
**Author:** ![Duck\_Duck\_Goose](https://avatars.discourse-cdn.com/v4/letter/d/50afbb/32.png) [@Duck\_Duck\_Goose](https://boards.straightdope.com/u/Duck_Duck_Goose)\ **Post date:** [July 2, 2002, 3:55am UTC](https://boards.straightdope.com/t/do-fleas-explode-at-high-altitude/116884/3 "2002-07-02T03:55:42Z")
> [@](#): > > \*\*someone claimed that dogs don’t get fleas in Denver because of the altitude \*\* Found this. [http://www.familyeducation.com/article/0,1120,8-21560,00.html](http://www.familyeducation.com/article/0,1120,8-21560,00.html) > [@](#): > > Tip #8: > Q: Is it true there are high-altitude places where fleas don’t bother pets? > A:There are some areas of the country that are not plagued by fleas. However they are not necessarily related to altitude. They’re more necessarily related to low humidity. Most areas of high altitude have low humidity. > > Think Denver or Reno or Tahoe, and many dry desert areas are flea-free, too. ---
**Author:** ![DarrenS](https://avatars.discourse-cdn.com/v4/letter/d/977dab/32.png) [@DarrenS](https://boards.straightdope.com/u/DarrenS)\ **Post date:** [July 2, 2002, 4:02am UTC](https://boards.straightdope.com/t/do-fleas-explode-at-high-altitude/116884/4 "2002-07-02T04:02:19Z")
Thanks for that DDG. I also found [this](http://www.colostate.edu/Depts/IPM/natparks/fleas.html) > [@](#): > > Optimal temperatures for larval development are 65 to 80F. Larvae need a relative humidity of at least 50%. So that rules out Denver. The only other reference I could find to this on the whole Web was on what seems to be a student’s personal [web page](http://www-sul.stanford.edu/depts/diroff/newsnotes/sept19.htm) - > [@](#): > > her move to Arizona included the purchase of a new home and the end of any fleas on the family’s dog. Apparently, the critters can’t live at Flagstaff’s altitude; they explode This sounds like prime UL material, yet I couldn’t find it debunked anywhere. Perhaps the “true” part, as often found in ULs, is that fleas can’t live at high altitudes. And perhaps the “exploding” part was just tacked on to make the “factoid” more interesting and aid in its propagation as a UL. ---
**Author:** ![Gary\_T](https://avatars.discourse-cdn.com/v4/letter/g/3ec8ea/32.png) [@Gary\_T](https://boards.straightdope.com/u/Gary_T)\ **Post date:** [July 2, 2002, 1:26pm UTC](https://boards.straightdope.com/t/do-fleas-explode-at-high-altitude/116884/5 "2002-07-02T13:26:12Z")
And just why would fleas be more prone to exploding than any other creature? Given that humans, dogs, and plenty of other insects survive at altitude, the notion strikes me as patently ridiculous. ---
**Author:** ![Motate](https://avatars.discourse-cdn.com/v4/letter/m/c0e974/32.png) [@Motate](https://boards.straightdope.com/u/Motate)\ **Post date:** [July 2, 2002, 4:19pm UTC](https://boards.straightdope.com/t/do-fleas-explode-at-high-altitude/116884/6 "2002-07-02T16:19:39Z")
I think it is due to the fact that fleas have an exoskeleton. I have heard a similar theory about cocokroaches. I was told that cockroaches are unable to fart because of the exoskeleton thing and that some mad scientist somewhere was inventing a pestcide that would give them gas. The idea was that the cockroaches would explode eventually after the gas expanded in their bodies. Yuuuuuuuuuuck! I am not saying that this is true,I am merely hijacking this thread. Don’t hit me.😉 ---
**Author:** ![Tars\_Tarkas](https://avatars.discourse-cdn.com/v4/letter/t/6a8cbe/32.png) [@Tars\_Tarkas](https://boards.straightdope.com/u/Tars_Tarkas)\ **Post date:** [July 2, 2002, 8:38pm UTC](https://boards.straightdope.com/t/do-fleas-explode-at-high-altitude/116884/7 "2002-07-02T20:38:57Z")
[Do Insects pass Gas?](http://www.straightdope.com/mailbag/minsectgas.html) And technical information on [Tracheal Breathing](http://www.ultranet.com/~jkimball/BiologyPages/T/Tracheal_Breathing.html) ---
**Author:** ![Gary\_T](https://avatars.discourse-cdn.com/v4/letter/g/3ec8ea/32.png) [@Gary\_T](https://boards.straightdope.com/u/Gary_T)\ **Post date:** [July 2, 2002, 11:35pm UTC](https://boards.straightdope.com/t/do-fleas-explode-at-high-altitude/116884/8 "2002-07-02T23:35:36Z")
> [@](#): > > \*Originally posted by Motate \* > **I think it is due to the fact that fleas have an exoskeleton.** As does every arthropod–insects, arachnids, etc. I gaurantee there are insects and spiders in Denver and Flagstaff. > [@](#): > > **Don’t hit me.😉** Oh sure, spoil all my fun…