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Hank sits down with clinical sexologist Dr. Lindsey Doe and talks about 'fighter sperm'. Then Jessi from Animal Wonders comes on to show off her Quaker Parrot the 'monogamous bird'.

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Hello and welcome to another episode of the SciShow talk show. The episode of SciShow where we talk to cool people about stuff. Today we're talking to Lindsay Doe, clinical sexologist and host of Sexplanations. go watch now or later. 

HANK: Hi Lindsay.

LINDSAY: Hi Hank. 

HANK: How's it going? 

LINDSAY: Great, how are you?

HANK: What are you up today? What have you been doing? I just wanna know. I want you to tell the story of how you lost your sperm on the way here. 


HANK: Let's start with - 

LINDSAY: So I'm thinking to myself "I'm gonna talk with Hank Green today. What are we gonna talk about? We're gonna talk about sperm of course. So I need to go to my office, which is just around the corner and get my sperm" and um... 

HANK: Which is this... 

LINDSAY: Which is that.. 

HANK: Right here... 

LINDSAY: Yeah, exactly. 

HANK: On a little stick. 

LINDSAY: Well it comes off even more.

HANK: Oh, okay. So you just have the sperm. 

LINDSAY: Right, and I got here. And I realized that the sperm had fallen off on the journey.

HANK: So somewhere on the streets of Missoula, there was a single lonely sperm. 


HANK: Which I shouldn't be showing you because there should be more dramatic tension for the fact that you did indeed find it. 

LINDSAY: It could have been crushed. 

HANK: Yeah. It could have been lost forever. 

LINDSAY: Or picked up. 

HANK: Yeah, I mean if I found it. If I saw this on the street, I would totally pick it up.


HANK: And take it home and show all my friends. 

LINDSAY: Where is your good citizenship? 

HANK: Well I figure, you know, it's on the street. 

LINDSAY: Yeah, yeah. 

HANK: It's lost. 

LINDSAY: Yeah, yeah. 

HANK: But you went back and you retraced your steps.

LINDSAY: I did. I went all the way to my office and then I actually got down on the ground and looked under the door to see if maybe it was there. Because I left my keys here. Then came back here defeated and there it was! On the sidewalk. 
HANK: On the sidewalk!

LINDSAY: So excited! 

HANK: Well, I'm very glad that we have our sperm today. So are we talking about sperm today? 

LINDSAY: Okay. So I want to know what you think are the purposes - purpose - what is the purpose or purposes of sperm? Human sperm.

HANK: Uh. Just to convey the genetic information of the man to the female. To the egg. To the genetic information of the female. So that those gametes can be mixed and turned into a human baby. 

LINDSAY: Okay. That's one great purpose. 

HANK: That's the main purpose. 

LINDSAY: That we know. Are there any other - 

HANK: To be clear, that's the reason why not only sperm exists but also all things. All life things. It's just all about - it's all about the sex. 

LINDSAY: Yeah, most of them. 

HANK: But there are more purposes. 

LINDSAY: What is another purpose? Do you know one? 

HANK: Uh. No. I feel like pretty much that's the whole purpose. 


HANK: But there's more. 

LINDSAY: Yes. What is kinda under debate, though some sperm experts - I think they might call themselves spermataurologists - 

HANK: Spermataurologists. It's better than spexperts. 

LINDSAY: I don't know if it's better, but it's great. Okay. They've looked under the microscope and see that we might have what's called kamikaze sperm, killer sperm, fighter sperm. That actually forty percent or higher of the sperm - forty percent of the sperm that are in an ejaculate are designed to fight off another man's sperm. 

HANK: What? So they're not even trying to... 

LINDSAY: Something just happened in this studio... 

HANK: To inseminate. What's that word? Impregnate. Infiltrate. So they're not going for the egg. 


HANK: They're - they're an attack sperm.

LINDSAY: So stop - die. 

HANK: So how does that work? 

LINDSAY: They're describing it as blocking. They'll use their tails as coils and they'll set up traps. And we think, under the microscope "oh my goodness. These are the lame, broken ones that have no death" 

HANK: Right. 

LINDSAY: But really what they're doing is they're creating walls. Barriers. Right? For the other sperm to go through. But some of them will actually go and naggghgh kill them. 

HANK: That's terrifying. I don't know why that's so terrifying. Like obviously I'm not going to be personally injured by a sperm. 

LINDSAY: No. Well no. But you wanna know what's even cooler?
HANK: What? Oh, there's more. 

LINDSAY: Well, let's say that you suspected that Katherine was not being monogamous.

HANK: Okay. 

LINDSAY: Your body would produce more fighter sperm. 

HANK: Ooohhh. That's awesome! So you could actually do a test. Not just to see if your wife is being faithful. But if your husband thinks you're being unfaithful. 

LINDSAY: Maybe. 

HANK: That's amazing!

LINDSAY: So you would produce more fighter sperm. 

HANK: Okay. So basically my sperm would become more awesome. But fewer of them would actually have the goal of impregnation. 

LINDSAY: Yes. If you consider an army awesome. 

HANK: Well, I mean...yes. In that- in that very man way that I just did where I was like suddenly I have....Do they have bazookas? Tell me about their weaponry. 

LINDSAY: They don't necessarily have a captain, which is what I think is the most fascinating part about it is that somehow this is all orchestrated if it's happening. Cause this is...

HANK: Still under some debate. 

LINDSAY: Yes. That they don't have...y'know a military leader.

HANK: There's no leader.

LINDSAY: ...that says you guys do this, though what they have found....a woman's cervix, which is kind of like the tip of the nose or the tip of the tongue, separates the uterus from the vagina, has a cervical plug in it for most of the month so that bad things don't go in deeper to her body. Well, during ovulation, the cervical plug transforms to create these channels that work like ladders and each's very similar to if I were to crack an egg and the egg whites were to come out. They're tiny little channels, only a sperm head or two heads wide, and so what will happen, is that some of the older sperm, some of the ones that aren't viable to begin with will actually make little coil blockades in these channels, so, y'know, other sperm can't get up that particular ladder.

HANK: So it's like, if it's not going to be me, it's not going to be anybody. 


HANK: That's...hardcore.

LINDSAY: Well, it's not going to be me, I'm the old king man who's going to die and I'm going to send forth Arthur. 

HANK: Ah. But hasn't Arthur already gotten through then, if it's plugged up? There are multiple channels. 

LINDSAY: And there are multiple Arthurs. There's 200 to 500 million so-called "Arthurs". 

HANK: That is a good point.

LINDSAY: I guess more- some- no, because some of them, right, they're the fighter sperm so they're going to be the Lancelots and the Merlins and...

HANK: (laughs)

LINDSAY: Yeah. Alright, so there's something that a lot of, um, the Internet is saying is gross and I want to hear what your thoughts are. This is...well, maybe gross is giving it away.

HANK: Okay. So the Internet says-

LINDSAY: I brought something for you.

HANK: So the Internet says something is gross, and she wants to know what I think about it. 

LINDSAY: Okay, let's say I didn't say it was gross. I brought something. It's really famous. What do you think it is?

HANK: (laughs) It's a famous thing. It's famous on the Internet.

LINDSAY: Yeah, it's famous on the Internet.

HANK: Just like me!

LINDSAY: Yeah, just like you!

HANK: Umm. And it's in a jar, and it's a liquid, and it's semi-transparent, and it contains some kind of sediment. There is-it's not just liquid, there's something in it. And it's actually got, well, I've got-I've got a clue now because it's got a label from the health food store where we live. 

LINDSAY: Yes, but that's only the jar. 

HANK: Oh. That's not the stuff? You could buy it at the grocery store?

LINDSAY: So the jar-no. No, no. Mmm-mm. 

HANK: No. Definitely not for sale at a a grocery store, is what that face tells me. Um. Is it a bodily fluid?


HANK: Did it come out of someone I know? 

LINDSAY: I don't know if you know him. 

HANK: Okay, so it came from a male. 

LINDSAY: It did. 

HANK: That's a good- that's a good guess. I don't feel like I've ever produced something that looks like this. 

LINDSAY: I'm gonna go with you have! 

HANK: Okay. 

LINDSAY: (laughing) and it just hasn't sat in a jar.

HANK: (laughs) I don't want to touch it anymore. It's not gross at all. So is this-is this semen?


HANK: and is this- why is it liquidy like this? Has it been dissolved in some water or does this just happen when you let it sit around?

LINDSAY: Be-right! Because of physics. 

HANK: Oh, it's physics. 

LINDSAY: So we did an episode on Sexplanations about some of my favorite things, and this was one of my favorite things because I realized that a lot of people probably haven't seen semen because it's ejaculated into their bodies or into a condom, or they're not playing with a biosex male. 

HANK: Right.

LINDSAY: Or-"Ah, I don't want to look at it!"

HANK: (laughs)

LINDSAY: Or a lot of people think that water has been added to it or that it is not normal semen that somehow-

HANK: Right. 

LINDSAY: -something weird is going on with that guy. But one of the greatest responses to explain the lack of viscosity is from-his name is Alchemydude667

HANK: Oh, thank you, alchemydude667!

LINDSAY: Yeah, thank you! And he wrote about how the gel state is not the easiest one for it to be in, and-

HANK: It's not the most stable state.

LINDSAY: Right, yes.

HANK: So it-

LINDSAY: -returns to...

HANK: ....huh! Neat!

LINDSAY: more of a liquid. 

HANK: That is-we have with us today, a special guest, the most famous sperm on the Internet. 

LINDSAY: (laughs)

HANK: I just wanna say that the information you have brought me today is information I did not know, and so full ten points, uh. I'm fascinated, very cool. Ten points is the maximum you can get.

LINDSAY: Awesome! I'll take them.

HANK: So now, I have a special guest for you! I have Jessi from Animal Wonders who will be bringing a Quaker parrot, a monogamous bird. 

HANK: Okay. So this is a Quaker parrot. What is his or her name?

JESSI: His name is Chopsticks. 

HANK: Chopsticks! That's a cute name.

JESSI: (laughs) Do you want to show them why? Say, "chop chop"! Say "chop chop"! Wanna say it for a seed? Say "chop chop"!

CHOPSTICKS: Chop chop!

LINDSAY: (gasps) AWWWW. 

JESSI: Good bird. 

HANK: (laughs) He's like, "I'm not gonna do it. Show me the seed."

JESSI: "I need baiting. Bribing."

HANK: "I am food motivated."

JESSI: Yes. 

HANK: So I was told that I could not that I could not touch Chop Chop-er, Chopsticks (laughs), because uh, because he is mean. He's being very nice to you

JESSI: Yeah. That's right, that's because he is bonded to me. Umm. 

HANK: So I shouldn't even touch you. Would he freak out?

JESSI: He probably would get a little bit upset if you touched me as well, yeah. You can put your hand closer, you can see what he does. 

HANK: I'm afraid. Oh, he's already opening his mouth.

JESSI: Yeah. (she and Hank laugh) He'll gape at you, and then lunge, and then laugh maniacally. You think it's funny

HANK: (laughs) 

LINDSAY: Wait, so is his connection to you part of the monogamy thing? Does he think that you're his soul-mate?

JESSI: Yes, he does. He thinks I'm his soul-mate.

LINDSAY: Really?

HANK: How do we-how does he feel about Augusto? 

JESSI: Oh, he hates him. He hates him.

HANK: Oh well. That's because you're cheating on him.


(All laugh)

JESSI: Shhh, he doesn't know! 

LINDSAY: Do you produce more sperm because she has a husband? 

(all laugh)

HANK: He thinks that's funny! 

JESSI: I don't think they would produce more sperm because they're going to be monogamous in the wild, and have cloacas and they don't have, y'know, things going inside the female. 

LINDSAY: Yeah, can you explain cloacas to me?

JESSI: It's like a hole, and a hole.

LINDSAY: Both male and female birds have them.

JESSI: Yes. 

LINDSAY: And the urea comes out of them.

JESSI: Yes. Everything comes out of one hole and then just rub them, and the sperm gets in there, and that's how eggs are made.

HANK: So is this a South American bird?

JESSI: They live in the tropical areas of South America, but these guys are interesting because people-there are so many of these guys where a huge influx of pet, in the pet trade in the 1970s, and they became an invasive species, they can tolerate cold weather. So there are quite a few places in the world where these guys have set up a sustainable colony. New York is one of them.
It's interesting, they tried to eradicate them because they make these huge nests, usually on telephone wires and poles. And I mean, if you Google it, you can see just these massive structures of twigs and they would weigh down, and it would cause damage to the electrical components.
Umm, so, they tried to eradicate them and, uh, in New York, they were working- they had these huge programs to try to get rid of these guys, and uh, then they started doing studies on their feces compared to pigeon feces and they realized that pigeon feces is more corrosive than the Quaker parrot feces, so they actually said, "Well, we don't mind the Quaker parrots quite as much as the pigeons, so we'll let you hang out."

HANK: "You're actually better."

JESSI: Yeah. 

HANK: "and see if you can completely out-compete pigeons." No more pigeons in New York City.

JESSI: Watch this. Ready...ahh, ahh-choo! 


HANK: Awwww!

LINDSAY: Yeah. I like you.

(All laugh)

LINDSAY: I think that's hilarious! I wanna know what your sperm looks like.

(Jessi and Hank laugh)

LINDSAY: It would tell us so much!

JESSI: Here, tell me what it looks like. It's a secret. (whispers to Chopsticks)

(all laugh)

HANK: Chopsticks, i just want to say thank you, thank you  for coming on the show today. OOH, my goodness, what did your neck just do?! And Jessi, thank you, and Lindsey of course, for bringing in both a model of a sperm and also actual, the degraded ejaculate. I don't know what we would do without you.
And to you, thank you for watching this episode of SciShow Talk Show, if you want to keep getting smarter with us here at SciShow you go to and subscribe. 

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