# Is anal sex anti-natural? And only humans do it? **URL:** \ **Category:** Factual Questions\ **Created:** [November 5, 2000, 9:57pm UTC](https://boards.straightdope.com/t/is-anal-sex-anti-natural-and-only-humans-do-it/39847 "2000-11-05T21:57:42Z")\ **Posts on this page:** 20\ **Page:** 2
**Author:** ![smartt](https://avatars.discourse-cdn.com/v4/letter/s/48db29/32.png) [@smartt](https://boards.straightdope.com/u/smartt)\ **Post date:** [November 6, 2000, 4:46am UTC](https://boards.straightdope.com/t/is-anal-sex-anti-natural-and-only-humans-do-it/39847/21 "2000-11-06T04:46:39Z")
> [@](#): > > _Originally posted by peace \* > **People say that the anus wasn’t originally created for sex.** Do not listen to wild rumors. Be your own man. What do_you\* say?. Well, what I really want to know is if the anus, BY NATURE, is made for sex - or not. What I want is a medical/biological/evolutionary overview about the subject. What’s my opinion? Well, I think that sex is NOT the original function the anus was built for. That’s my, uh, “medical” opinion, and I have some medical data to support this - drumrolls, please - **theory** of mine. Yep: it’s a theory that I have, and some physicians share with me. I’m not the mistra know-it-all kind of guy, so if you know something different about the subject, a discussion would be very healtly. And please, let me make it clear that I’m not AGAINST anal sex. No no no, you’ll never hear ANY judgemental thing about it from me mouth, nosireebob. What I’m looking for is for MEDICAL evidence that the anus isn’t - or is, why not? - originally made for penetration. > [@](#): > > **It has no natural lubrication.** Not true, it has. So, the feces have easier time passing through. But a litle added grease on the business parts helps. Are you sure that this can be considered a lubrication? And I ask it in medical terms, of course. > [@](#): > > **But this is really an anti-natural thing?** Define **anti-natural.** Well, for me it’s something that’s not pertinent to the human nature. For example, people don’t breath underwater; so they use anti-natural means (scubas) do achieve this. If the anus was not created for penetration and sex, then anal sex is anti-natural. And I don’t mean it in a judgemental way, as in “ew, anal sex, gross gross!”, roit? It’s a purely scientific denomination, that’s all. > [@](#): > > Anal sex occurs at this very time somewhere in nature, between two consenting adults. In this sense, it’s natural. Not exactly. That’s consensual sex. Look, I’m not interested in the moral implications of anal, or any other kind of “non-missionary” sex. And even if science and medicine says that the anus isn’t made for sex, that will be just another piece of info for my readers. That won’t stop 'em for having anal sex, neither stop talking their g/fs into it. Heck, **I’m** brazilian, I love anal sex!But I wanna know if the anus is made for penetration - or not. Why? My readers love to ask about it. But It’s just trivia, that’s all. > [@](#): > > **Animals do it too, or this is something that we, humans, just learn from porn flicks?** Please, rephrase your you question, I do not read it as alternative -\*\* or\*\*. In general, see above about animals. To put it more clearly: do animals have anal sex? A reader asked for that, and all I wanna do is 1. Do animals have anal sex? 2. If so, which ones? 3. Do they make it for pleasure, as we human beings? I have heard that some animals - monkeys or tigers, I think - sodomize other males of the group as a form of humiliation, to put em under submission. I don’t know if that’s true, tho; I won’t start any Urban Legend, so I choose to check the hard facts first. Does anybody know? ---
**Author:** ![zen101](https://avatars.discourse-cdn.com/v4/letter/z/c68b51/32.png) [@zen101](https://boards.straightdope.com/u/zen101)\ **Post date:** [November 6, 2000, 4:54am UTC](https://boards.straightdope.com/t/is-anal-sex-anti-natural-and-only-humans-do-it/39847/22 "2000-11-06T04:54:58Z")
[QUOTE] \*Originally posted by smartt \* \*\* > [@](#): > > \*Originally posted by peace \* > > > [@](#): > > > > **It has no natural lubrication.** Not true, it has. So, the feces have easier time passing through. But a litle added grease on the business parts helps. > > Are you sure that this can be considered a lubrication? And I ask it in medical terms, of course. A lubricant is a lubricant. It **may** be intended to lubricated exiting feces, but trust me, it works the other way too. peace is right tho, a little extra lub is usually a good plan (think of it like KY-Training Wheels). As for animals doing it. I know for a fact that make dogs do copulate. Most people seem to think this is a matter of dominance rather than pleasure. Personally I’m twisted, I think most sex is about dominance and it just happens to be a pleasurable way of going about being dominant \* or\* submissive. Maybe dogs feel the same way too. It has to beat being chewed to pieces. ---
**Author:** ![smartt](https://avatars.discourse-cdn.com/v4/letter/s/48db29/32.png) [@smartt](https://boards.straightdope.com/u/smartt)\ **Post date:** [November 6, 2000, 5:23am UTC](https://boards.straightdope.com/t/is-anal-sex-anti-natural-and-only-humans-do-it/39847/23 "2000-11-06T05:23:33Z")
> [@](#): > > \*Originally posted by zen101 \* > A lubricant is a lubricant. It **may** be intended to lubricated exiting feces, but trust me, it works the other way too. Well, okay, then it’s a lubricant. It works the other way? Fine, that’s a really valuable info. But just as a formality, for the moment I’m considering K-Y as an “anti-natural” thingie. IMHO, K-Y Jelly was the best invention since the fire, the wheel and the cable TV; but for the moment, let’s say that anal sex is not natural, but forced . And let me reiterate: that’s not a moral judgement, just a medical theory. I wanna know if the anus, the BIOLOGICAL structure we politely call rectum (heh!), IS made for sex - **or** not. If people use it for sex anyway is another, completely different issue, and an issue I’m not particulary interested. It’s not about moral implication; it’s all about biology and evolution, roit? What I want is just a hard fact: MEDICALLY speaking, the anus is made for sex? Yes? Why? No? Why not? Simple as that. ---
**Author:** ![yojimbo](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/yojimbo/32/232_2.png) [@yojimbo](https://boards.straightdope.com/u/yojimbo)\ **Post date:** [November 6, 2000, 5:26am UTC](https://boards.straightdope.com/t/is-anal-sex-anti-natural-and-only-humans-do-it/39847/24 "2000-11-06T05:26:02Z")
> [@](#): > > 1. Do animals have anal sex > 2. If so, which ones? From [here](http://www.iaccess.com.br/~dennis/homosexual.htm) > [@](#): > > These include such practices as the mounting of one male by another (e.g. Langurs, pig-tailed macaques, baboons, orangutans, chimpanzees, > bonobos) (Sommer 1990; Oi 1991; Lorenz 1963; Yamagiwa 1992; Hayaki et al. 1989), including mounting with anal penetration (e.g. stumptailed macaques, squirrel monkeys) (Sommer 1990; > Maple 1977), and mounting with anal penetration and ejaculation (Japanese macaques, rhesus macaques, gorillas) (Sommer 1990; Gadpaille 1980; Edwards and Todd 1991). Masturbation > of other males has also been reported, including mutual masturbation (e.g. stump-tailed macaques) (Sommer 1990) as well as genital-genital contacts (e.g. bonobos) (Enomoto 1990), at > times leading to ejaculation (e.g. gibbons) (Edwards and Todd 1991). Fellatio has also been reported for stumptailed macaques (Sommer 1990). Other perhaps related behaviors include > sniffing/inspecting the genitals/anal region of other males (e.g. stumptailed macaques,) (Sommer 1990), “displaying” an erect penis to other males (e.g.vervet macaques)(Henzi 1985), and > urinating a few drops on the other male during the display (e.g. squirrel monkey)(Castell 1969). In some cases males have shown a preference for their homosexual partners over > heterosexual partners (e.g. rhesus macaques)(Sommer 1990). By the way we aren’t all American here. And the Americans that are here aren’t the ones that are behaving like a\*\*holes. ---
**Author:** ![CurtC](https://avatars.discourse-cdn.com/v4/letter/c/ce73a5/32.png) [@CurtC](https://boards.straightdope.com/u/CurtC)\ **Post date:** [November 6, 2000, 5:27am UTC](https://boards.straightdope.com/t/is-anal-sex-anti-natural-and-only-humans-do-it/39847/25 "2000-11-06T05:27:57Z")
smartt, go out and buy the book _Why Things Are, Volume II: The Big Picture_ by Joel Achenbach. In it, Joel attempts to answer the question “Why do sexual turn-ons vary so greatly from person to person?” Here’s some excerpts from Joels answer: "You would think, based on the Darwinian logic of survival of the species, that every human being would be aroused by similar thoughts of straightforward, heterosexual intercourse… “The problem is, many sexual turn-ons are completely disassociated from the act of mating - they might not involve another person, even in fantasy…” Next he quotes, John Money of Johns Hopkins: " ‘Diversity may be an inevitable evolutionary trade-off - the price paid for freeing the primate brain to develop its uniquely human genesis of syntactical speech and creative intelligence.’ " ## (Joel again): “Dr. Money is saying that erotic variability is not itself an adaptive trait, but rather the _side effect_ of an adaptive trait, the development of the linguistic brain.” So if you’re asking whether other animals have anal sex, they likely don’t, because it doesn’t make new little animals. The question is really about why humans _do_. ---
**Author:** ![Fiver](https://avatars.discourse-cdn.com/v4/letter/f/e274bd/32.png) [@Fiver](https://boards.straightdope.com/u/Fiver)\ **Post date:** [November 6, 2000, 5:27am UTC](https://boards.straightdope.com/t/is-anal-sex-anti-natural-and-only-humans-do-it/39847/26 "2000-11-06T05:27:59Z")
No references, nor even any definite statements, but I’m pretty sure male chimpanzees sodomize other chimpanzees (other males, females, prepubescents, what-have-you). I also STR that some species of goats practice posterior speleology. So there’s two species already that also practice anal sex. ---
**Author:** ![absoul](https://avatars.discourse-cdn.com/v4/letter/a/bc8723/32.png) [@absoul](https://boards.straightdope.com/u/absoul)\ **Post date:** [November 6, 2000, 5:29am UTC](https://boards.straightdope.com/t/is-anal-sex-anti-natural-and-only-humans-do-it/39847/27 "2000-11-06T05:29:28Z")
> [@](#): > > \*Originally posted by smartt \* > > 1. Do they make it for pleasure, as we human beings?\*\* Hold on, let me ask some animals. _puts on dr. dolittle hat and walks outside_ ---
**Author:** ![pezwookiee](https://avatars.discourse-cdn.com/v4/letter/p/9d8465/32.png) [@pezwookiee](https://boards.straightdope.com/u/pezwookiee)\ **Post date:** [November 6, 2000, 5:30am UTC](https://boards.straightdope.com/t/is-anal-sex-anti-natural-and-only-humans-do-it/39847/28 "2000-11-06T05:30:56Z")
Okay, let’s look at this from a different angle, shall we? Kissing is unhygenic (and actually a relatively recent phenomenom in human behavior). Then again, I think we can all agree that sometimes a good kiss feels incredibly natural as an outlet for a human feeling. Is kissing natural? The answer to this question will be the same as the answer to “Is anal sex natural?” ---
**Author:** ![Arjuna34](https://avatars.discourse-cdn.com/v4/letter/a/eb8c5e/32.png) [@Arjuna34](https://boards.straightdope.com/u/Arjuna34)\ **Post date:** [November 6, 2000, 5:35am UTC](https://boards.straightdope.com/t/is-anal-sex-anti-natural-and-only-humans-do-it/39847/29 "2000-11-06T05:35:10Z")
> [@](#): > > \*Originally posted by Jophiel \* > \*\* > > > [@](#): > > > > It’s just a gathering of snubby, PC-oriented, american morons. > > Not true! Look at this thread! > [Are MAC PC’s superior IBM Compatible PC’s?](http://boards.straightdope.com/sdmb/showthread.php?threadid=44835) \*\* LOL! 🙂 Arjuna34 ---
**Author:** ![yojimbo](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/yojimbo/32/232_2.png) [@yojimbo](https://boards.straightdope.com/u/yojimbo)\ **Post date:** [November 6, 2000, 5:36am UTC](https://boards.straightdope.com/t/is-anal-sex-anti-natural-and-only-humans-do-it/39847/30 "2000-11-06T05:36:27Z")
You could also do a search on Bonobo chimps. They do the nasty aswell 😉 ---
**Author:** ![smartt](https://avatars.discourse-cdn.com/v4/letter/s/48db29/32.png) [@smartt](https://boards.straightdope.com/u/smartt)\ **Post date:** [November 6, 2000, 5:43am UTC](https://boards.straightdope.com/t/is-anal-sex-anti-natural-and-only-humans-do-it/39847/31 "2000-11-06T05:43:25Z")
Thank you for the info, guys. **That’s** what I call hard facts! And **Absoul** , I’ve read somewhere that sows are the only animals able to have orgasms. I’m not sure if that’s right, but I don’t think the scientists found that out using Dr. Doolitle’s techniques… 😃 **pezwookie** , that’s a damn valid point, but we’re almost falling into the moral trap again. Morals aside,you have to agree that there aren’t natural impediments for the act of kissing mouth to mouth; besides, chimpanzees and some fishes do it all the time. Of course, kissing can be considered “unhygienic” - but it’s not like fatal diseases can be transmitted by spit, roit? On the other side (literally, hehe), the muscular structure of the anus is made for let things out, but not **in** (well, at least not in with some effort, that is). By this point of view, the anus is NOT made for sex. So, it’s not natural. It’s POSSIBLE to have anal sex? Oh, sure. Thank God for KY. But that’s not the answer I’m looking for. Let me be more clear: When Mother Nature created the anus, she said “Thou, my brown-eyed fella, shalt be responsible for getting the poo out AND JUST THAT, MMKAY?”, or did she said “And I shall name you anus and make you a two-way street, so go out and have some fun!”? ---
**Author:** ![peace](https://avatars.discourse-cdn.com/v4/letter/p/c68b51/32.png) [@peace](https://boards.straightdope.com/u/peace)\ **Post date:** [November 6, 2000, 6:32am UTC](https://boards.straightdope.com/t/is-anal-sex-anti-natural-and-only-humans-do-it/39847/32 "2000-11-06T06:32:06Z")
## As I said, I like curious people. Even if they are interested in anal sex. After all, one can buy a newpaper for a quarter and read everything about politics… but anal sex info is hard to come by. In general, curiousity beats drugs or loitering and many other things. I can be serious, but I want to have fun, too. So, please excuse any tong-in-cheek remarks. And, for a change, let me deviate from election politics, political correctness, genetics, computers, and other routine. You figured it almost right, Smartt: anus was NOT created for sex. Other, highly specialized organs were\*. Although penis comes close, the urine is sterile and it flows in the same direction (we’ll touch on this soon again). Nature has its way of economizing, though: in lower animals, birds, only one organ is present called cloaka. I have no idea how cloakal sex feels, sorry. Anal sex, as such, is not practiced in the fauna. It’s not only bad manners, there is at least one good biological reason, which comes to mind: it’s not hygienic. What if a tiger get urethritis after putting another one into submission? Imagine the joy of the submissed one when he hears the news? And there are no condoms and no urologists for miles and miles. If two non-sterile cloakas (cloakae for purists) come into contact, no harm is done. Smartt, I asked you to define your “anti-natural” (I think, you actually mean unnatural, but I ain’t a f… lawyer, I do not hang on technicalities). To me, whatever happens in nature is natural. Consentual is not an antithesis. So, I’ll wait till you explain what exactly you’d like to know. About breathing under water: try it and you are likely to die. Anal sex is not nearly as dangerous. I have a litle hypothesis about anal sex. Actually, it should be called anorectal, because the anus per se is a very narrow muscular ring, capable of both voluntary and non-voluntary contactions, somewhat similar to the vaginal entrance, just incomparably stronger. (Do not ask me how it is possible to have both voluntary and nonvoluntary constrictions. The Nature has many gimmicks, it’s one of them. Think about your swallowing: it’s voluntary but at some point it becomes involuntary).The man has a pleasure-seeking instinct: normal people (and we are talking about normal people here) seek pleasure and avoid pain and suffering. As you know, not only “classic” back-and-forth penis-in-vagina sex is pleasurable for both genders. To me, it sounds more like a rape. During a “normal” sexual session, the activity may or may not involve the primary sexual organs. The latter “were created” and widely used for making babies. In addition, the nerves which ultimately lead to the genitalia and anorectum (remember cloaka? historically, they were the same), start together, as one “main”. Apart from pure mechanical stimulation (the rectum and the vagina are close neighbors), some criss-crossing is very likely. So, nerve stimulation in one tube is perceived in the brain as if coming from the neighbor. (Rough analogy: ask somebody to touch your back with !, 2 or three fingers. As your assisstant put the fingers closer and closer, you’ll be incapable of telling the number of fingers). Did I shed some light for you in this poorly lit area? You know their names, in Latin/Greek,English, Portuguese… If not, I’m sure the CDopers will gladly help you, the mods permit. ---
**Author:** ![smartt](https://avatars.discourse-cdn.com/v4/letter/s/48db29/32.png) [@smartt](https://boards.straightdope.com/u/smartt)\ **Post date:** [November 6, 2000, 6:56am UTC](https://boards.straightdope.com/t/is-anal-sex-anti-natural-and-only-humans-do-it/39847/33 "2000-11-06T06:56:15Z")
> [@](#): > > \*Originally posted by peace \* > \*\*Did I shed some light for you in this poorly lit area? > \*\* Oh, sure! And you also made me think of an alternative line of questioning. Let’s state that there is REPRODUCTION and there is SEXUAL PLEASURE. Both are independent things. The anus was NOT created for REPRODUCTION, that I’m 99% sure - but somebody can always prove me wrong, so I won’t be so certain about it. The anus can be a source for SEXUAL PLEASURE, but it’s not SPECIALIZED for that - or it is, and we just don’t know? Fact is: at first, the anus presents some natural defenses against penetration. The obvious one is that is hurts like hell. But for some people, pain equals pleasure, so I don’t think it’s exactly an issue. The other one is the nature of the muscular contractions of the rectum. I’ve read somewhere that the anal muscles are the only ones in the entire human body that are naturally CONTRACTED. All the other muscles are naturally relaxed, but to relax the anus you need to make a conscient effort. I’ll wait for confirmation on the above before going further. ---
**Author:** ![Major\_Feelgud](https://avatars.discourse-cdn.com/v4/letter/m/3be4f8/32.png) [@Major\_Feelgud](https://boards.straightdope.com/u/Major_Feelgud)\ **Post date:** [November 6, 2000, 8:45am UTC](https://boards.straightdope.com/t/is-anal-sex-anti-natural-and-only-humans-do-it/39847/34 "2000-11-06T08:45:31Z")
> [@](#): > > \*Originally posted by smartt \* > \*\*People say that the anus wasn’t originally created for sex. It has no natural lubrication. But a lot of girls (and guys) seems to have lotsa pleasure with that practice. But this is really an anti-natural thing? Animals do it too, or this is something that we, humans, just learn from porn flicks? \*\* Humans have self-conciousness or conciousness. We like experimentation. Even as cavemen I’m sure we shouted into caves to hear the echos, drew on the walls to see the pictures, skipped stones over water. Copulation is instinctive, no one has to show you how to do it, 2 children growing up on a desert island will do it. Anal sex, masturbation, oral sex, foot sex, armpit sex, ear hole sex, tit fucking (sorry, do not know of another name for this), that’s all part of our inquisitive nature as human beings. It’s like “If I stick my penis in this hole and rubbing it gives me pleasure, why not in this hole, or this hole?” Yes, I would say it’s natural because of human nature. Don’t forget, we’re just another lifeform on this planet. Animals do it I’m sure. I’ve haven’t looked close enough to find out. Our family used to have two male cats and the dominant would mount the other, but I never checked to see if there was anal penetration. ---
**Author:** ![yojimbo](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/yojimbo/32/232_2.png) [@yojimbo](https://boards.straightdope.com/u/yojimbo)\ **Post date:** [November 6, 2000, 8:52am UTC](https://boards.straightdope.com/t/is-anal-sex-anti-natural-and-only-humans-do-it/39847/35 "2000-11-06T08:52:07Z")
> [@](#): > > tit fucking (sorry, do not know of another name for this) Soapy tit wank & A pearl necklace. The fight against ignorance continues 😛 ---
**Author:** ![Major\_Feelgud](https://avatars.discourse-cdn.com/v4/letter/m/3be4f8/32.png) [@Major\_Feelgud](https://boards.straightdope.com/u/Major_Feelgud)\ **Post date:** [November 6, 2000, 9:10am UTC](https://boards.straightdope.com/t/is-anal-sex-anti-natural-and-only-humans-do-it/39847/36 "2000-11-06T09:10:14Z")
yojimbo: I meant a name that you can use in public, or polite company. E.g. If you’re teaching a sex ed class you can say masturbation, oral sex, anal sex etc., but you can’t very well say “And this is a soapy tit wank”. ---
**Author:** ![Lynn\_Bodoni](https://avatars.discourse-cdn.com/v4/letter/l/e47c2d/32.png) [@Lynn\_Bodoni](https://boards.straightdope.com/u/Lynn_Bodoni)\ **Post date:** [November 6, 2000, 9:32am UTC](https://boards.straightdope.com/t/is-anal-sex-anti-natural-and-only-humans-do-it/39847/37 "2000-11-06T09:32:08Z")
Smartt: Go to the Straight Dope homepage. Click on Archive. Enter “Sex”. Search. Enjoy. Don’t bother us again until you’ve memorized every article you find there. By the way, the answer to your question is there… ---
**Author:** ![smartt](https://avatars.discourse-cdn.com/v4/letter/s/48db29/32.png) [@smartt](https://boards.straightdope.com/u/smartt)\ **Post date:** [November 6, 2000, 9:48am UTC](https://boards.straightdope.com/t/is-anal-sex-anti-natural-and-only-humans-do-it/39847/38 "2000-11-06T09:48:20Z")
> [@](#): > > \*Originally posted by Lynn Bodoni \* > \*\*Don’t bother us again until you’ve memorized every article you find there. > \*\* Is that a requirement for being on this board? Or just another arbitrary rule invented by some powermad admin? Just curious, not flaming. I love the idea of Free Speech, and when people try to take it from me… well, it pisses me off. ---
**Author:** ![Lynn\_Bodoni](https://avatars.discourse-cdn.com/v4/letter/l/e47c2d/32.png) [@Lynn\_Bodoni](https://boards.straightdope.com/u/Lynn_Bodoni)\ **Post date:** [November 6, 2000, 10:00am UTC](https://boards.straightdope.com/t/is-anal-sex-anti-natural-and-only-humans-do-it/39847/39 "2000-11-06T10:00:33Z")
> [@](#): > > \*Originally posted by smartt \* > \*\* > > > [@](#): > > > > \*Originally posted by Lynn Bodoni \* > > \*\*Don’t bother us again until you’ve memorized every article you find there. > > \*\* > > Is that a requirement for being on this board? Or just another arbitrary rule invented by some powermad admin? > > Just curious, not flaming. I love the idea of Free Speech, and when people try to take it from me… well, it pisses me off. \*\* Not a requirement, but a really good idea. And it would be good manners. Most of your questions have already been answered by Cecil Adams. Incidentally, Cecil’s columns have been gathered in books, and you can order them online, too. ---
**Author:** ![smartt](https://avatars.discourse-cdn.com/v4/letter/s/48db29/32.png) [@smartt](https://boards.straightdope.com/u/smartt)\ **Post date:** [November 6, 2000, 10:01am UTC](https://boards.straightdope.com/t/is-anal-sex-anti-natural-and-only-humans-do-it/39847/40 "2000-11-06T10:01:33Z")
BTW,\*\* Lynn Bodoni \*\*, I just found the link to Cecil’s entry about gay animals. Very concise and informative, all I needed. Thank you very much. But tell me something… WHY THE FUCK NOBODY FROM THIS BOARD POINTED ME TO THIS LINK IN THE FIRST PLACE? It could have saved a lot ot time, but noooo, looks like people don’t know HOW to argue in a civilized way. Oh well, I don’t care. Some guys think that the fact that they can access the Internet put em a level above the other human beings. Yeah, right. [Previous page](https://boards.straightdope.com/t/is-anal-sex-anti-natural-and-only-humans-do-it/39847.md?page=1) [Next page](https://boards.straightdope.com/t/is-anal-sex-anti-natural-and-only-humans-do-it/39847.md?page=3)