How Fleas Work


Josh: Josh Clark

Chuck: Charles W. "Chuck" Bryant

Vo: Voiceover Speaker

Vo: Welcome to Stuff You Should Know from HowStuffWorks.com.

[MUSIC]

Josh: Hey, and welcome to the podcast. I'm Josh Clark. There's Charles W. "Chuck" Bryant and Jeri. And this is Stuff You Should Know.

Chuck: Hey, dude. How's it going?

Josh: Good. How are you, man?

Chuck: Good.

Josh: Uh, Chuck?

Chuck: Yes.

Josh: Chuck.

Chuck: Yes.

Josh: You love New York, right?

Chuck: Sure do.

Josh: I love New York too.

Chuck: It's a good city.

Josh: It's a great city.

Chuck: In fact I think we suggested first that someone do that on t-shirt.

Josh: I love New York?

Chuck: Yeah.

Josh: I don't recall that.

Chuck: Sure.

Josh: Oh, man.

Chuck: You haven't been getting your checks?

Josh: No.

Chuck: Oh, well, I'll make sure you get those.

Josh: I don't think the person who really created that has been getting any checks for a long time.

Chuck: Yeah, that'd be an interesting little thing to look up. I bet you it's unknown to history.

Josh: Who did it?

Chuck: Yeah, who did "I Heart New York" in that iconic font.

Josh: I think it is known.

Chuck: Oh, it is?

Josh: Yeah, I think it is known. I think it was probably somebody who was contracted by like-not the Chamber of Commerce but some tourism board, maybe, for New York.

Chuck: Like the guy who wrote "Rudolph the Red Nosed Reindeer"?

Josh: Yes, be he got his copyright back from Montgomery Ward. Remember?

Chuck: Yeah, that's true.

Josh: It's like the most benevolent thing any corporation has ever done. My mind is still blown. And that was two Christmases ago that we first learned about it.

Chuck: Yeah.

Josh: Anyway, I wonder, though, if "I Heart New York" is actually in the public domain or if it's just been pirated so much that they just don't even try to police it any longer.

Chuck: Maybe. Because we, for our Canadian tour, Umi designed the "I Canadian Leaf Canada" shirts.

Josh: Right.

Chuck: In place of the heart.

Josh: Yeah.

Chuck: And those are great. You can actually buy those in our store.

Josh: Yeah, that's true.

Chuck: We never plug our store.

Josh: No, we don't. It's crazy. It's like we just pretend it doesn't exist, but it does exist.

Chuck: Yeah, I felt like a jerk for a second there by plugging the store. But I was like, "Wait a minute. I don't think we've ever plugged it."

Josh: We're allowed to do that.

Chuck: Yeah, you can actually buy shirts.

Josh: Yeah, it's on our website, StuffYouShouldKnow.com. In the top nav, I think it says "store." You just click that. All the stuff. The classic SYSK bowling shirt is on there.

Chuck: Classic.

Josh: There's just a lot of stuff.

Chuck: Yeah.

Josh: Good stuff. So, anyway, New York. New York made the news recently, as it does from time to time, Chuck, in that it was discovered that the flea that was responsible for spreading bubonic plague has been found alive and well on the rats of New York. Did you know that?

Chuck: What?

Josh: Yeah. Now the people who conducted the study, they just rounded up like some rats and tested them. And they're like, "Yeah, this one's got it. Yeah, this one's got it." They were quick to point out that the bubonic plague itself, which is called Yersinia pestis-it's a bacterial that causes the plague, which is nasty. Right?

Chuck: Yeah.

Josh: Did we do-we didn't do a bubonic plague episode.

Chuck: We did black plague.

Josh: Yeah, or Black Death or something.

Chuck: Yeah.

Josh: That was a good episode. I think this is different.

Chuck: Sure.

Josh: But the bubonic plague, it's caused by a bacteria, Yersinia pestis, and they said that they didn't find Yersinia pestis in the fleas, they just found the fleas, the oriental rat flea, on the rats of New York. So they're saying, you're probably not going to catch the plague. It turns out that most people who get the plague, all seven of them every year in the U.S., get them here in the South.

Chuck: Oh, really?

Josh: Yeah.

Chuck: That's nice.

Josh: So steer clear of the Southern rats, but the New York rats could just as easily spread it, too, because everything is in place for it to spread.

Chuck: Right.

Josh: So fleas.

Chuck: Man, that's an old-school intro.

Josh: It was okay.

Chuck: No, it was good.

Josh: I'm a little rusty.

Chuck: So, yeah, fleas. We've done ticks, and we've done flies, and we've done bees.

Josh: Termites was a really good one. Remember them?

Chuck: Termites. We have dabbled in the insect world.

Josh: Yeah, and this is a Tracy Wilson article, who wrote like all of the insect articles.

Chuck: She did.

Josh: You could tell this one came later and she's like, "I'm so tired of talking about the thorax that I'm not even going to mention it in this one. Just go read any of the other articles."

Chuck: Yeah, and there was one line in here where she was like, "Yeah, and like the lifecycle is like most other insects."

[LAUGHTER]

Josh: Right. Don't be dumb.

Chuck: Go read any of these hundred other ones I've written about it.

Josh: Yeah.

Chuck: So fleas are the bane of my existence. And I'll pepper throughout the podcast my experience.

Josh: Okay.

Chuck: With my animals and fleas, because I've had a couple of major infestations in my life. But they are parasites. And that means that they feed on the host, in this case drinking your blood like a tick does.

Josh: Yeah. Yeah, that's true. For some reason I don't equate fleas with ticks, though, even though they're so similar. But, yes, they both drink blood. And in fact what the flea eats is called a blood meal.

Chuck: That's so gross.

Josh: It's not just called dinner. They call it a blood meal.

Chuck: [LAUGHS] Yeah, there are about 2,000 species of flea. We are mainly going to concentrate on, I think they call it, the cat flea.

Josh: Well, that's the most common here in the States.

Chuck: Yeah.

Josh: And the cat flea is not just attracted to the cat; it also likes dogs, it also likes humans.

Chuck: A little bit.

Josh: And then there's the dog flea, which is also attracted to cats and dogs and humans, but it'll also attach itself to raccoons, pigs, livestock, wild animals-it's not very picky.

Chuck: Yeah, like the flea you get on the squirrel in your yard, that squirrel that haunts you in your yard, is going to be different than the one on your pet inside, largely because that squirrel is never laying down for hours on end during the day, where the flea will, you know, find a nice lazy dog and be like, "This looks like a great place to fornicate and lay eggs and have a blood meal or two, do my whole thing with my mouthparts."

Josh: Yeah, but for that reason, if you ever do find a squirrel that's stunned or possibly dead just lying there, don't roll on it, because the fleas will jump out onto you.

Chuck: Have you seen those photos, they're old, but of the dead squirrels with the action figures? I showed these to Scotty the other day. He had never seen the-

Josh: Oh, I should I tell everybody. I just made an inquisitive look.

Chuck: Oh, yeah. It's super old. But someone at one point found a dead squirrel and got like G.I. Joe action figures and, as if he had hunted it, like, you know, doing a hunting pose like with his leg propped up on the squirrel's head.

Josh: [LAUGHS] Oh, yeah.

Chuck: And there's another one with the guy like holding up the squirrel's head like it was a big game.

Josh: No, I haven't seen that.

Chuck: It's really funny.

Josh: That is.

Chuck: And it's funny because they didn't kill these squirrels to do it, because that would be a different deal.

Josh: The squirrel died naturally.

Chuck: I'm assuming the squirrel was just-

Josh: -by being hit by a car.

Chuck: -yeah, run over in the road, and someone was like, "Hey, let me get my G.I. Joes out like they were hunting big game."

Josh: Right. Because that's what you do.

Chuck: But you should not ever stage one of these by killing an animal.

Josh: No, and you really probably shouldn't stage them anyway because the people who did stage them probably did get fleas. And they got cat fleas-or dog fleas, I'm sorry.

Chuck: And maybe the plague.

Josh: So, Chuck.

Chuck: Yes.

Josh: We said that they feed on blood.

Chuck: Yes.

Josh: They have blood meals. They are kind of picky but not altogether picky when it comes to the kinds of hosts that they have. Right?

Chuck: Yeah.

Josh: And that you said that they're parasites. And they're specifically ectoparasites, which means they live outside of the body.

Chuck: Yeah.

Josh: Rather than endoparasites, which live inside the body.

Chuck: Like a tapeworm. Gross.

Josh: Right, but the thing that they have in common is that all they do is take, take, take, and they give nothing back in return.

Chuck: But grief.

Josh: Right. Which you don't really want, so it's not a symbiotic relationship, it's a parasitic relationship that you have with your fleas.

Chuck: Yeah, it's a one-way street.

Josh: Right.

Chuck: Fleas are the little guys, of course. I think you know what we're talking about, but we will describe it. It's wingless. They have these hard plates called sclerites that their body is covered with, which is why if you've ever had a flea and just mashed them between your thumb and finger and been like, "Take that," and then he goes, "Doing," and jumps off. You're like, "How did that happen?" It's because they're covered with these small plates to help that.

Josh: Sclerites.

Chuck: Yeah, you've got to really work to kill a flea like with your fingernails.

Josh: And it not only protects fleas from fingernails, it also protects them from falls, because they will jump; they're known to jump.

Chuck: Yeah, should we go ahead and talk about that?

Josh: I think we should. It's pretty amazing stuff really.

Chuck: It's pretty neat. What are the stats there?

Josh: So a flea can jump about seven inches vertically. That's up and down.

Chuck: Yeah, seven to eight.

Josh: And 13 inches horizontally. Right?

Chuck: So, big deal, seven inches.

Josh: Right. So remember in the cockroach episode?

Chuck: Yeah.

Josh: Where they can move 50 body lengths in a second, which to humans is like 250 miles an hour?

Chuck: Yeah.

Josh: This is very similar. In human terms, a flea's jump would be a 250-foot vertical jump from a human. That's a lot.

Chuck: That is crazy.

Josh: And a 450-foot horizontal jump.

Chuck: Yeah, so when the flea jumps six inches you should be very impressed.

Josh: It is impressive, because the current record for a standing long jump is 12 feet, and a flea could jump the equivalent of 450 feet.

Chuck: That's right. Setting world records from your dog's butt on a daily basis.

Josh: Just one of the amazing things about a flea.

Chuck: And creepy. The exoskeleton is smooth-looking when you're looking at the little flea on your knee, but what it really has is a bunch of little tiny hairs sort of combed back, like a cool guy would do.

Josh: Like the Fonz.

Chuck: Like the Fonz would do. They're pointing away from the head, and those little backwards-pointing hairs mean that they can sail through dog or cat's fur without getting hooked. But if you go and try and get the flea out, it will serve as a hook, like Velcro, and anchor it in that fur.

Josh: Exactly. Which is why fine-tooth combs work, but like a brush won't. Because the fine-tooth comb is so close together, the tines are so close together that the flea still just can't hang on. But a brush, it's like, "Pff, that was nothing."

Chuck: Yeah, and if you have a flea infestation or a bit of a flea problem, your flea comb is going to be a good way to tell, but it's not going to get rid of that many fleas.

Josh: No.

Chuck: You can flea-comb 24/7 and still have fleas.

Josh: It's the canary in the coalmine.

Chuck: Yeah, but it's a good place-like, if you do that or if you separate the hair and you see the dirt, flea dirt they call it, that's like either dried blood or poop, and a good sign that your dog or cat has fleas.

Josh: Yeah, it's not flea eggs.

Chuck: No.

Josh: Flea eggs are clear.

Chuck: That's right. And smooth.

Josh: So fleas, like you said, suck blood. They eat what are called blood meals, which I just can't get past. And they do so because they have specialized mouthparts, which is basically a combination of two saws on the side that puncture your skin.

Chuck: Those are called-hmm. L-A-C-I-N-I-A-E.

Josh: I was going to say laciniae.

Chuck: Right.

Josh: And they form a saliva channel, which will come into play later on.

Chuck: Yeah.

Josh: And then they also surround what's called the epipharynx, which is the needle that sucks the blood.

Chuck: That's right. And that is a stylet altogether. It forms a stylet, which is the puncturing organ. And it basically it all just jabs into your skin and that epipharynx is working with basically stomach pumps to suck that stuff out.

Josh: Yeah, which is pretty impressive because it requires a lot of suction to get that blood out.

Chuck: Sure.

Josh: So, again, pretty impressive with fleas. Jump far, suck really hard.

Chuck: They do suck.

Josh: Yeah.

Chuck: All right. Right after this break we are going to talk a little bit about that life cycle that we mentioned earlier.

[MUSIC]

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Chuck: Just by clicking your mouse, huh?

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[MUSIC]

Chuck: All right, Josh. Flea life cycle.

Josh: Yeah, again, you can just look to Tracy Wilson and be like, "There just like other bugs."

Chuck: It's like a butterfly.

Josh: It's still worth mentioning. So an adult has some eggs. And those eggs are totally smooth. They don't just appear smooth like the flea itself; they are totally smooth. And one of the reasons why they're smooth is because the eggs are meant to fall off of the host. Like the flea itself is having a blood meal on your leg, laying some eggs, pooping, just doing all sorts of crazy stuff. Right? And when it lays its eggs, the eggs fall off and they fall into, if you're in the house, carpet fibers deep in the carpet, cracks in your hardwood floors.

Chuck: Oh, man. That's the worst.

Josh: Outside they'll fall into the soil. And they are just meant to be sequestered away.

Chuck: Yeah, they need, in order to hatch and develop they need a warm, moist environment, about 70 degrees Fahrenheit, 70 to 85% humidity.

Josh: Although they'll go as low as like 45. Anything below that and they're just not going to hatch.

Chuck: Yeah, exactly. That's why a good winter freeze is going to help your flea problem.

Josh: A dry winter freeze.

Chuck: A dry winter freeze. Your eggs are going to hatch in about twelve days, and that twelve-day span is one of the things that makes fleas so maddening, because you can think you've killed all your fleas and then there are tens of thousands of them that are going to hatch twelve days later.

Josh: Right. And you go kill those. And by the time you kill those they've already laid eggs and the cycle continues, which is why-and we'll get into it-you have to kill the fleas and their eggs to take out a flea infestation.

Chuck: Yeah, at the same time. It's challenging.

Josh: And so the egg is sitting there in your hardwood floor or your carpet or out in the soil. And after about twelve days, if the conditions are right, it'll hatch and it'll turn into a larva. And the larva goes through three instars, or cycles of development, stages of development, and they molt after each one. And after the third instar, it says, "I'm going back to my home in the cracks in the floor and spin me a nice cocoon," and turn into a pupa.

Chuck: That's right. And like we said, it's sort of like a butterfly. An adult flea is eventually going to emerge from that cocoon. It's not nearly as pretty as a beautiful, iridescent butterfly.

Josh: No, and it's nasty too.

Chuck: And a butterfly doesn't have blood meals.

Josh: Right.

Chuck: As far as I know. Ooh, there's your next sci-fi movie.

Josh: Blood Meal Butterfly?

Chuck: Yep.

Josh: Look for it after Sharknado 3, premiering this March.

Chuck: [LAUGHS] In a population of fleas about half of them are eggs, which is why we said they're so problematic to get rid of. And only about 5% reach adulthood. And one reason is because females can only lay the eggs if they've had that blood meal. If they're starving, they will die before they reproduce.

Josh: Yeah, and what's neat about them, too, is when they're in the pupal stage and they're up in their cocoon and hanging out and developing and everything-because they emerge from the cocoon as an adult. But while they're a pupa they can tell through either vibrations and/or sensing body heat-

Chuck: That's crazy.

Josh: -whether there is food nearby.

Chuck: Like, "Should I hatch?"

Josh: Right. Because they feed on warm-blooded animals. So they can tell. And they find these signals in the environment. And if the signals are right, they'll come out of their cocoon in, I think, a week or something like that. If the signals aren't right, they can stay in their cocoon for up to a year.

Chuck: Yeah.

Josh: And they actually camouflage themselves. They roll around their cocoon in like debris and hair and stuff like that, which is pretty cool.

Chuck: Yeah, that's why if you have like a vacation house and you've eradicated your fleas and then left for the winter-or I guess you'd be there in the winter. You've left for the spring-

Josh: Right.

Chuck: -depending on how you-I don't know how you do your vacation house. But when you come back, like that could be the signal, "Hey, there are hosts here now." Like, it doesn't mean you've been overrun by fleas that whole time. They've just been laying in wait for you to come back.

Josh: Yeah, and then you're back, and they're saying, "We're here."

Chuck: Ugh.

Josh: "Let us get some blood meals on you."

Chuck: The females can lay about 20 eggs at a time or about 500 during a long life.

Josh: I saw up to 2,000 in another article.

Chuck: Oh, well, then let's say between-

Josh: 500 to 2,000.

Chuck: -20 and 2,000.

Josh: Yeah, but, again, they won't lay eggs if they haven't eaten.

Chuck: No.

Josh: One of the other cool things about the flea larva is that they actually don't eat blood meals. They eat just about everything else: hair, dead skin cells-

Chuck: That's so gross.

Josh: -flea droppings, nasty, nasty things, just about anything that they'll find in the cracks in your floorboards or in your carpet or out in the soil. Right?

Chuck: That's right.

Josh: But then once they hatch, they go after the blood meal. One of the other things that the flea larva eats are tapeworm eggs, which makes fleas, again, super nasty and dirty little creatures because once they eat those tapeworm eggs, they grow up to become fleas that have tapeworms.

Chuck: Yeah, the tapeworm actually forms in the gut of the flea. It can be that tiny. And then all of a sudden your animal has tapeworms because they got bitten by a flea who injected that junk into your dog.

Josh: Or, more likely, you accidentally ate a flea or a flea got into your food.

Chuck: Ugh.

Josh: Or your dog ate the flea. The tapeworm lodged itself in your dog's gut. The tapeworm eggs were excreted through your dog's rectum-

Chuck: And then you eat that dog poop.

Josh: -onto its bedding. You pet your dog, and then you touch your mouth, and the tapeworms crawl into your mouth, the tapeworm eggs. And then now you're infected. So there's like 80 different ways that you can become infected with tapeworm just from fleas, and specifically dog fleas are the ones that carry tapeworms most likely.

Chuck: Fleas on dogs or the dog flea?

Josh: The dog flea.

Chuck: Okay. Um, so that's nasty. Here's some more nastiness for you. The reaction that you get when you get a flea bite or your dog gets, you know, when your dog is scratching, that is from the junk in the saliva of the flea.

Josh: Specifically the Cte f1 protein.

Chuck: Yeah, and it affects some people and animals more than others. It was really bad on my dog Charlie. Like, she had the hair falling out and the bald spots and the hot patches. It was just-

Josh: She was like, "These fleas are driving me crazy."

Chuck: I know. It was terrible. And the same thing can happen to people. You know, if you get a flea bite, you can see sometimes you a few little bumps.

Josh: Yeah, some people react to it worse than others. But everybody pretty much gets bumps. Those bumps make it even worse because you can scratch it, and some of those bumps will have bacteria, flea excrement, around them.

Chuck: Mm-hmm.

Josh: When you go to scratch them, you can break the skin and actually move the flea excrement, that's dirty as all get out, into your newly opened break in the skin, and you get all sorts of nasty infections from that.

Chuck: Yeah, you can also get murine typhus in the southern and southwestern parts, here were we live. And that is caused by the bacteria Rickettsia typhi, and mainly in the cat flea and the oriental rat flea, but that's one of the things you can get when the flea is defecating while they're eating. You scratch and you get that infected waste in the scratch, or, you know, if you've broken your skin.

Josh: So you get typhus from it.

Chuck: Good god.

Josh: From flea poop that you scratch into your skin. And then, of course, we talked about the plague, which is pretty interesting. The plague bacteria actually infects the flea itself, and it develops this film in the flea's midgut, so when the flea goes to eat a blood meal, it can't digest all the way. So then it goes to feast on the next person, and when it punctures your skin, it actually barfs up the undigested blood meal, that's now infected with the plague, into your skin. Now you have the plague.

Chuck: Man, when you hear words like midgut and blood meal and mouthparts.

Josh: And barf.

Chuck: Like, barf is the least offensive of all those.

Josh: [LAUGHS]

Chuck: That sounds cute.

Josh: So we can understand why everyone wants to get rid of fleas. But some people learned to love fleas, especially in the 19th century. And we'll talk about those people and their flea circuses right after this.

[MUSIC]

Josh: Chuck.

Chuck: Yeah.

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Chuck: I do.

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Chuck: That is great. I will raise you some turkey chili, though, my friend, and some corned beef spiced steak. How about that?

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Chuck: Just go to BlueApron.com/STUFF.

[MUSIC]

Chuck: All right, Josh. You mentioned flea circuses. I always thought that flea circuses were just fake and that they used magnets and other little things to like move the bicycle. And that can be a flea circus.

Josh: Sure.

Chuck: Those are called, I believe-

Josh: Illusory flea circuses?

Chuck: No, they have a name, "humbug" flea circuses.

Josh: Oh, that's cute.

Chuck: But there were, and I guess still are in some places, flea circuses that actually attach little leashes and chains to fleas, and they do things. They pull things around.

Josh: Yeah, because here's another astounding thing about fleas, they can lift up to 60 times their bodyweight.

Chuck: That's crazy.

Josh: So they're enormously strong.

Chuck: Yeah.

Josh: Sixty times. Like, think about it, man. Like imagine lifting 60 times your body weight.

Chuck: Can't do it.

Josh: You'd be crushed.

Chuck: You'd be crushed.

Josh: That's like a huge rock to you. You know?

Chuck: Yeah.

Josh: That's a boulder.

Chuck: That's a boulder.

Josh: So fleas can lift their equivalent of boulders, and these boulders, especially in the 19th century, but starting about in the 1600s, came in the form of things like chariots, coaches, hearses, just things that, like, say, a horse would draw but in miniature.

Chuck: Yeah, and apparently before that even, in the last 1500s, a guy named Mark Scaliot, in 1578, he was a watchmaker. And apparently watchmakers were the first dudes who had the idea to attach a flea to a chain. And in 1578 he did so. It was a lock consisting of eleven different pieces of steel, iron, and brass, which together with the key belonging to it, weighed only one grain-whatever one grain was.

Josh: It's like a pound and a half.

Chuck: No. No way.

Josh: So this is the late 1500s?

Chuck: Yeah. And he was the first guy who was like, "Hey, this little flea can actually carry something."

Josh: Right. So that caught on, but apparently the paying public didn't catch on to what was really going on, which was these guys had figured out how to actually train fleas. One of the first things you have to teach them is to not jump. And apparently you train them not to jump by keeping them in a sealed container.

Chuck: I was going to say by beating them.

[LAUGHTER]

Josh: Right. By like holding their parents hostage.

Chuck: Right.

Josh: You keep them in a jar, I guess a see-through jar so they can see their parents on the other side are being held hostage.

Chuck: Yeah.

Josh: But they jump and jump, and they get nowhere, and they learn jumping is futile.

Chuck: So a very shallow something, I guess?

Josh: Yeah. And then after they learn not to jump, you tie them up to this harness, this very tiny harness, and then they live in the harness for the rest of their lives.

Chuck: Which isn't long.

Josh: No, it's about three months.

Chuck: Yeah.

Josh: But, so let's say a flea lives a year. The first six months it has to mature to about the age where it can learn and it's big enough to put in a harness. You spend three months training it. And then it has a performing life of three months, where it's basically just living in this harness carrying chariots around for people's entertainment.

Chuck: There are probably people out there feeling bad about the flea.

Josh: Yeah, but don't forget the plague and flea excrement.

Chuck: Blood meals.

Josh: Yeah, all that stuff. It is kind of sad, to an extent.

Chuck: Oh, come on.

Josh: But in the 1600s apparently, the public thought that the flea circus trainers were sorcerers. That was a big thing. Because that explains it actually just as well.

Chuck: Well, they really caught on in places like Oktoberfest in Germany. They loved it.

Josh: They still do. I saw a video of a dude in Germany, like today, showing his flea circus off.

Chuck: That seems like a very German thing to do. You know?

Josh: Sure.

Chuck: We train the fleas to pull the things.

Josh: Is that Andy Kaufman?

Chuck: Sure. Coney Island and then Long Beach in California and New York City, places like Blackpool, England. Wherever there were circuses and freak shows and stuff like that, you might find a flea circus going on.

Josh: Yeah, and there's a dude named Andy Clark who's got one going now. He's got his hands on 19th century manuals, magazine articles, reviews of the real flea circuses. And he's re-creating them, I guess. But we'd be remiss to not mention "L. Bertoli." Isn't that his name?

Chuck: Who?

Josh: Oh, L. Bertolotto.

Chuck: Who was he?

Josh: He was like the flea circus guy, just a legend in the field.

Chuck: Oh, gotcha.

Josh: He was the chief flea circus dude.

Chuck: You go over in his house and he's got like fleas doing the dishes and-

Josh: Pretty much.

Chuck: -fleas cleaning up after him.

Josh: Yeah. So, Chuck, flea circus: kind of hard to do. Most people just want to get rid of fleas.

Chuck: Yeah.

Josh: So there are some ways.

Chuck: Yeah. And like I mentioned, I've had two major infestations, one is Los Angeles, where I could not find-here is my advice. This is off script. If you want to get rid of your fleas, try and find the source area.

Josh: Find the head flea.

Chuck: Find the head flea and take a meeting. Work out a negotiation between the two of you.

Josh: Right.

Chuck: And it should work out.

Josh: No chariots.

Chuck: No chariots.

Josh: Let all the parents go.

Chuck: So find your source. And in L.A. I could not find my source. It was driving me crazy. And finally I was outside. I thought, "Let me go in the yard." And we had this sort of a-

Josh: Dead squirrel?

Chuck: No, it was a garage on the side of the house.

Josh: Filled with dead squirrels?

Chuck: Filled with dead squirrels, and that was it. And on the other side of the garage it was like two feet of space about 15 feet long in between that and the fence. And that's just the place where nothing ever went.

Josh: Oh, yeah.

Chuck: You know?

Josh: Except the dogs.

Chuck: Oh, yeah. Except the dogs. And I was walking over there. And what I do is I walk around the yard barefoot if I'm looking outside because-

Josh: Yeah, that's a thing.

Chuck: Yeah. You look down and see if they jump on you. And I walked around the corner to this thing, dude, and in five seconds I had probably a thousand fleas on my.

Josh: Ah.

Chuck: Just crawling all over me.

Josh: Was it sandy over there at all?

Chuck: Hmm. It was kind of dirty and it was dank and dark.

Josh: Okay, yeah, humid.

Chuck: Yeah.

Josh: And warm, I imagine.

Chuck: And just not like-like I said, it was not well traveled.

Josh: Yeah.

Chuck: And, dude, I was like, "Alright. This is it." And I did the thing I don't normally do, which is get a lot of chemicals and sprayed all over it.

Josh: Did you set it on fire?

Chuck: Set it on fire.

Josh: Blew it up?

Chuck: And pooped on it. And that did it.

Josh: "Here's some of my excrement, fleas."

Chuck: And then I had a situation here in Atlanta where I actually had a guy come out and spray nematodes instead of chemicals.

Josh: Oh, yeah.

Chuck: You can apparently spray your basement and house and floorboards with nematodes.

Josh: Those are flat worms, right?

Chuck: Yeah, they're living things, apparently, that, I guess, eat the fleas?

Josh: I would guess, yeah.

Chuck: I have no idea, but that worked. And I also used what were-

Josh: Are you overrun with nematodes now?

Chuck: No. They were great.

Josh: They left?

Chuck: Yeah. Sprinkle a little on your coffee.

Josh: So, those chemicals you mentioned, there are some pretty cool chemicals.

Chuck: Yeah, there are some topical treatments that you can use on your animals, which they say they're safe. I try to avoid them just because-I don't know. I just don't think that chemicals that seep into the skin of your animal is ever good.

Josh: No, I mean, you make a good point.

Chuck: You know?

Josh: Yeah. Which is why-

Chuck: But I've been forced to use them, which I hate.

Josh: But if you could control the fleas in the environment, you could conceivably not have to use the chemicals on the dog.

Chuck: That's what the nematode guy said. He's like, "I don't ever use that stuff." He said, "You stop it before it starts." And I was like, "Well, good for you. You've got tons of nematodes in that can."

Josh: You've got a fancy-pants dog.

Chuck: But, when it comes to those topical things, IGRs, insect growth regulators.

Josh: My favorite is the chitin synthesis inhibitor.

Chuck: That's mean.

Josh: It basically creates mutant fleas.

Chuck: Soft fleas.

Josh: That never grow their exoskeleton right, which means they never develop fully, which means they're toast.

Chuck: Yeah. Which means they can be killed by dog scratches and bites and things.

Josh: Yeah.

Chuck: Those IGRs, that I mentioned, keep fleas from hatching because they mimic flea hormones. And some of these things will kill just the eggs, some kill adult fleas, some kill both.

Josh: You pretty much want something that kills it all.

Chuck: Yeah, you want to get the worst thing you can get for the flea.

Josh: Yeah. So if you do have an infestation, Tracy Wilson recommends some steps to take all at the same time. You don't want to do one or the other. You want to treat your pets and the dank area between your garage and the fence at the same time.

Chuck: Mm-hmm.

Josh: You want to wash all of your pets' clothing, all of their-

Chuck: Their bedding.

Josh: -their bedding.

Chuck: Their sweaters.

Josh: All that stuff. You want to wash it like five million times in the hottest water you can, probably with bleach if you can find it. Which it's not that hard; just go to the store. You want to bathe your pet. You want to use a flea comb. You want to-

Chuck: You've got to vacuum a lot.

Josh: A lot.

Chuck: Like every day, really.

Josh: She says at least every other day.

Chuck: Yeah.

Josh: Is that what you said?

Chuck: Well, I mean, every day if you really want to-

Josh: Yeah.

Chuck: -if you're really angry.

Josh: I would recommend twice a day.

Chuck: Yeah. And don't just vacuum and then put it in the closet. If it's a canister or a bag, you want to empty that immediately outside.

Josh: Nice.

Chuck: You know?

Josh: Yeah. And you want to chase squirrels away.

Chuck: Yeah, and there's a lot of stupid home remedies that say they work that don't-brewer's yeast, garlic, vitamin supplements, ultrasonic collars, flea collars. None of that stuff rally works. Trust me.

Josh: Chance.

Chuck: I got this one more thing on sand fleas. Did you read this?

Josh: Yeah.

Chuck: Want to talk about it?

Josh: Sure.

Chuck: Sand fleas are found in the tropical areas. I know they're in Florida, but it mentions the Caribbean, South America, and South Africa.

Josh: I think that they were native to the Caribbean.

Chuck: I'm sorry, sub-Saharan Africa. Oh, okay. Gotcha.

Josh: And they were taken to Africa in the slave trade, actually.

Chuck: So that's how they spread?

Josh: Yeah, which is just-yeah.

Chuck: So if you've ever heard of chigoes or chiggers or jiggers or niguas or piques or bicho-de-pés, these are all names for the sand flea. And this lady was studying them. And she said-she's a Ph.D. student named Marlene. And she was studying ways to prevent tungiasis infection in Madagascar, which is spread by fleas, these sand fleas. And she said, "How are these things reproducing?" And she said, "Look, I've got a flea." And they host in the body. These are different kinds of fleas. They actually root under your skin and live there.

Josh: Forever.

Chuck: Yeah, so it's disgusting. Like you have to extract them.

Josh: Right. It's not just disgusting, too, once they move in and live there and they'll move in as groups, often. They spend the rest of their life there. Over time walking becomes painful. Eventually walking becomes impossible. And all of a sudden, there goes your livelihood. So apparently this article mentions it affects the poorest of the poor. So especially in sub-Saharan Africa it's a real problem among the poverty-stricken areas because you get a sand flea in your foot and that's it. You're toast a year later.

Chuck: Pretty much. So she noticed that she had one between her toes. And she said, "You know what? Let me just let it burrow and see what happens." And she did. And it lived a lot longer than usual, two months. And she said it was still regularly expelling liquid from its abdomen. But she never got any eggs. And the reason this happened, she learned, and they now have a new theory cooking, is because she put a sock and shoe over it and didn't let any other fleas in there. So basically this flea never had sex. And so it never laid eggs. And what they theorize now is that these female fleas can basically lay there in a waiting state for longer than they should ever be able to live, waiting for a male flea to come around and fertilize the mature eggs.

Josh: Science.

Chuck: Science. So now they think basically that this is the deal. And they don't know quite how that's going to help them with fighting it, but they do know that it takes two to tango, for sure.

Josh: In your foot.

Chuck: In your foot. Having sex under your skin.

Josh: And speaking of sex and fleas, we have to mention The Autobiography of a Flea, which was an anonymous erotica book written in the 19th century.

Chuck: What?

Josh: I think the 1880s. It was huge in London. And it is about a flea that tells the tale of a girl it's attached to, who becomes the sex toy of a bunch of priests.

Chuck: What?

Josh: The Autobiography of a Flea.

Chuck: Wow.

Josh: And I guess that's it. You've got anything that can top The Autobiography of a Flea?

Chuck: Definitely not. Flea fan fiction is the ultimate.

Josh: So if you want to learn more about fleas, you can type the word "fleas" into the search bar at HowStuffWorks.com. And since I said search bar, it's time for listener mail.

[CHIMES]

Chuck: Spoiler alert on this, people. This has to do with movies that you may have not have seen. So stop the podcast now-

Josh: That is so nice of you to do that.

Chuck: -if you don't want to be spoiled about Birdman in particular, which we have already talked about.

Josh: Okay.

Chuck: "Guys, for the last few years I have cringed and groaned every time you make an error or a sweeping statement about films. Chuck, you discussed Guillermo del Toro as the director of The Orphanage, and he had nothing to do with the making of that film." I misspoke. It's The Devil's Backbone, which was about an orphanage.

Josh: Didn't he-wasn't he an executive producer, though?

Chuck: Also directed by a Latin American. No. But I was thinking of The Devil's Backbone. So he's right.

Josh: Okay.

Chuck: "Chuck, you also stated once that James Cameron has not made any good films since Terminator 2, ignoring the fantastic blend of comedy and action that is True Lies."

Josh: Oh, yeah. That was a pretty good movie.

Chuck: I didn't like it. That's why I didn't mention it. But when it comes to some movies that changed filmmaking, I had a strong suspicion that would be my first listener mail. So, "Josh's criticisms of Birdman, he suggested first that the scene where Riggan confronts the critic represents the director's pulpitting to the critics. He says, "The critics who have attacked him." And he says, "That can't be right, because the guy has gotten universal praise for his movies."

Josh: I'm sure he's been criticized, potentially unfairly, in the past.

Chuck: That's what I think. "And the ending of Birdman, Josh, it is heavily implied"-and we had a bunch of people say this actually. "It is heavily implied earlier in the film that the type of psychosis he suffers from his daughter also shares. The moment when he return to the room to find-she returns to find that her father has gone out the window, we hear sirens indicating that he has in fact jumped to his death in reality, but she looks out the window and up to the sky, seeing a hallucinatory image. He will now live on for her as Birdman, and no longer her never-there father. Her reaction is also strongly indicative of this as her face does not reflect that of a sane person seeing a human flying through the air, but instead a blissful ignorance." So I've heard that theory, that she is, you know, he did jump to his death and she just like suffers this psychotic breakdown, or that he actually did kill himself on stage and all of that last stuff is not reality.

Josh: But who's reality is it?

Chuck: I don't know.

Josh: Oh, who cares?

Chuck: [LAUGHS] He also takes us to task on 8½ being the birth of surreal cinema, because that goes to Un Chien Andalou from 1929, and that Citizen Kane was the genesis of dark lighting-not so, because film noir goes all the way back to 1920 with The Cabinet of Dr. Caligari and M in 1931.

Josh: I'll bet this guy is fun to watch movies with.

Chuck: And, dude, this is the tame version. He was actually-it was funny because he was kind of rude, but then he was like, "I love you guys." So I think-

Josh: "I just-I want to wear your skin."

Chuck: [LAUGHS] I think he was just being cheeky. And also too, by the way, Dial M for Murder, that was Anatomy of a Murder that you were thinking of, from Otto Preminger.

Josh: I looked it up.

Chuck: Or maybe not. But there was a movie called Anatomy of a Murder by Otto Preminger.

Josh: Yeah. Yeah. Dial M-right. Yeah. We made the correction-

Chuck: Dial M for Murder was Hitchcock, yeah.

Josh: Right. That's what you said. And I said, "I don't know." And then you kept talking, and I looked it up.

Chuck: Right.

Josh: And apparently some people didn't hear me correct and say, "Yes, you are right about Hitchcock." I guess it was Anatomy of a Murder I was thinking of.

Chuck: Perhaps.

Josh: Or there was one that was just called M that was also noir.

Chuck: Well, M is 1931 and it was the first talkie to use film noir as a wide release.

Josh: Gotcha. And that was Preminger?

Chuck: No. [LAUGHTER] Maybe it was.

Josh: We're going to need a correction for this correction.

Chuck: He said, "This email has already exceeded the length that moderate sanity would allow." And it was even longer. And I disagree, sir. You're clearly crazy.

[LAUGHTER]

Josh: From the first sentence.

Chuck: I'm just kidding. That is Travis Duclow. And he's a good guy. He's a film buff and took us to task.

Josh: Thanks a lot, Travis. That wasn't too bad.

Chuck: No.

Josh: We've survived worse.

Chuck: That's right.

Josh: If you want to correct us or throw in your two cents or whatever, because film appreciation, I don't care what you say, is subjective.

Chuck: True.

Josh: You can tweet to us @SYSKPodcast, you can join us on Facebook.com/StuffYouShouldKnow, you can send us an email to StuffPodcast@HowStuffWorks.com, and, as always, join us at our home on the web, StuffYouShouldKnow.com.

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Vo: For more on this and thousands of other topics, visit HowStuffWorks.com.

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