Biology of sexual orientation

Here is an excellent article on the biology of sexual orientation. We all know this is a contentious issue — are we born with an orientation, or is it a 'choice' that people make? — and the article just lays the facts out for us and points out some of the lacunae in our knowledge.

First, I'll confess to my own position on that nature-nurture debate: it's both and it's neither, and the argument is misplaced. There is no template on the Y chromosome that triggers a sexual response when Pamela Anderson enters the visual field, but there almost certainly are general predispositions that are a product of genetics, development, and learning. Even if there were no genetic component at all, it shouldn't matter in social policy or in our interactions with other people: my own heterosexuality is fairly strongly fixed and was acquired before I was really aware of it, and I'm willing to see other's homosexuality, no matter what its source, as equally fixed, and changing it as both undesirable and unjust.

The article discusses animal studies, in particular with mice and rats, and there it is clear that sexual orientation is established by a biological factor, hormone exposure. Hormone exposure in developing brains causes remodeling that fixes a behavioral response, and in lab animals, you can tinker with that directly, removing a hormone or adding an exogenous one, and controlling for other variables in the environment. You can't do that with people — can you imagine the reaction to an NIH grant proposal that suggested injecting pregnant women with hormones to induce homosexuality? Can you imagine anyone agreeing to being that kind of experimental subject? — which means of course that there is a dearth of direct evidence for such phenomena in us. We rely on natural experiments that accidentally manipulate embryonic hormone exposure, and then we try to pick apart the effect in a clutter of other uncontrolled variables. The authors point out that there is precisely one study that shows a statistical effect of modified prenatal exposure to a gonadal hormone that is correlated with later sexual orientation.

There is one very interesting explanation for the apparent difference between rodents and humans. Rodent sexuality is tied to hormone levels throughout their life, with cycles of sexual interest and activity in both males and females. Humans have uncoupled sex from hormonal regulation to a much greater degree, so we can have sex any time of the month or any season of the year (and isn't that a good thing?). This suggests an interesting evolutionary hypothesis: perhaps the lability of sexual orientation in humans is a side-effect of unshackling sexual behavior from tight cyclic hormonal regulation. Freeing us from the bonds of the spring rut or the monthly estrus means human brains aren't quite as locked in to a single sexual stimulus. (This can't be the whole explanation, of course, since even species with restricted mating seasons can exhibit same-sex mating behaviors.)

Anyway, you know what they say: read the whole thing. It's a good, measured article that promotes a sensible view of sexual orientation and also recommends more research on the issue.

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Yeahhhhhhhh! Canadians 'trigger a sexual response', eh!

By Richard Harris, FCD (not verified) on 10 Aug 2007 #permalink

Why do people forget that it just takes a single gene in Drosophila to turn them into displaying homosexual behavior....

I've always thought that the comparison with left-handedness is pretty appropriate. I don't know if you can find a "left-handed gene," but no one would argue that handedness is learned, either, as every father who tried to teach his son to throw left-handed could tell you.

(in fact, from what I've heard, twin studies tend to find stronger correlations in homosexuality than in handedness)

An interesting thing about handedness: just as there are "bisexuals" there are people who have conflicting handedness. For example, my neighbor growing up threw and batted right-handed, but kicked left-footed.

Just as Male and Female are extremes ends of a spectrum (note nipples on men, structural homologs of penis and clitoris) so too, I expect, Gay and Straight are extremes of a spectrum. In both spectra there are some scattered throughout the middle. Black and White are just shades of Gray.

What I don't really understand is this: (OK, I _do_ understand it, but I like to pretend)

We have two areas of human experience. There is Religion, and Sexual Orientation. On the one hand, we bend over backwards to allow people the freedom to choose their religion, to have it or not have it, whatever. On the other hand, we're rigidly locked into heterosexuality and ask 'what makes people gay?'

No one sits around and goes 'Are people biologically predisposed to being Christian?' 'What gene makes people Pastafarians?' etc. Yet we continue to fight for special privilege under law for people of practicing faiths.

What does it matter where a person's orientation comes from? I admit it's a facinating biological study, just as 'What makes someone Christian' is a facinating sociological and psychological study.

But I don't see where these questions have anything to do with people's rights to live their lives as they want too.

By Brendan S (not verified) on 10 Aug 2007 #permalink

The problem is, unsurprisingly, that if god has personally told you that a given behaviour is wrong then no amount of reason and appeals to stop being a bigot will ever work. Look at the recent fuss here in the UK when the Catholic Church insisted on its (literally) God-given right to continue to discriminate against gay people in the face of legislation making this illegal. No amount of discussion about the biology of sexual orientation is going to make an impact on this type of thinking (or more precisely believing)

I don't care whether anybody, straight or gay, made a choice or is compelled to be "that way". My only problem is seeing beyond their sexual orientaion to their character.
I can respect and honor and befriend the gayest, flamingest, transvestite queen in the world, and I have (hello Nora Neat, daaarling- hope you are still around and doing well)
On the other hand, I have no use for a rapist, or an aspiring rapist.

I agree with #5 and would like to add just one more thought or two.

Researchers has already shown quite clearly, people DO CHOOSE to become homosexual, and usually only after they have been preyed upon by older homosexuals. Why is this knowledge always ignored? Why do people look for answers in genes and hormones when the Truth is already known?

Oh, yes. Whenever "truth" is capitalized, I know I can absolutely trust whatever blather comes out. Sheesh. Name one researcher. Show me one peer-reviewed study. Or stop blathering.

Rev Paul T Hipple,

No, we don't. That simple.

Once these guys figure out why I'm bisexual, maybe they can explain why I'm a furry.

By Tukla in Iowa (not verified) on 10 Aug 2007 #permalink

Paul Cameron, LOL!

I wish I could say "you're way too over the top to be for real", but I live in the U.S.

By Tukla in Iowa (not verified) on 10 Aug 2007 #permalink

Paul Cameron, the EX-psychologist? The one who was expelled from the American Psychological Association for ethical violations? Right. Any REAL studies or researchers?

No one sits around and goes 'Are people biologically predisposed to being Christian?'

You are fr*ming the question wrong. Plenty of people sit around and ask: Are people biologically predisposed to being religious?, or "predisposed to attributing conscious intent to natural phenomena", or whatever. Putting Christianity in there is the equivalent of asking "Are some people biologically predisposed to wearing buttless leather trousers?"

I'll second that LOL and i'll raise you a "PZ, can you please ban woot?"

By Carpworld (not verified) on 10 Aug 2007 #permalink

@Rev. Hipple - Reverend, I've checked out your website, and I'm wondering, do you think that Sen. Brownback is some kind of closet hippie/communist/atheist, or just that he's not as much of a supporter of the dominionist position as Rep. Tancredo? And what do you think of the Baptists for Brownback site?

Question for PZ or others who might know - the article mentions animal species with "two (or more) separate sexes". To which I responded "!?!?" What species are being referred to here?

Rev. Hipple:
"Researchers has already shown quite clearly, people DO CHOOSE to become homosexual, and usually only after they have been preyed upon by older homosexuals"

So, have the researchers shown that a large number of altar boys become homosexual?

By Alan Wagenr (not verified) on 10 Aug 2007 #permalink

Researchers has already shown quite clearly, people DO CHOOSE to become homosexual, and usually only after they have been preyed upon by older homosexuals.

Because it's most likely a correlational relationship. Pedophiles tend to prey on more effeminate boys, many (but not all) of whom grow up to be gay.

Putting Christianity in there is the equivalent of asking "Are some people biologically predisposed to wearing buttless leather trousers?"

/me stares blankly for long seconds, then blinks

Um, sorry about that. What were we talking about?

By Tukla in Iowa (not verified) on 10 Aug 2007 #permalink

Oops - I know what species have 2 sexes, of course. I meant what species have "or more".

Dr. Cameron spoke at my church several years ago. He is a good Christian gentleman and was very persuasive. Yes, I heard he had some sort of professional difficulties. He told me about a horrible rumor spread on the interweb by his detractors who disagreed with his scientific conclusions, and that was not unusual in his scientific field. I don't know about all that, but I can personally vouch for his integrity and humility.

Blessed are those who are persecuted because of righteousness, for theirs is the kingdom of heaven.
Matthew 5:9-11

For civil rights purposes the biology of sexual orientation should be irrelevant. In a civilized society it should be nobody else's damned business which gender a person chooses to sleep with.

By Steve LaBonne (not verified) on 10 Aug 2007 #permalink

NickM, if I had to guess, I'd suspect they're talking about species that have males, females, and hermaphrodites. Though I'm hard-pressed to think of a species off the top of my head with all three occurring naturally...

I'm with Carpworld--PZ, ban woot.

Question for PZ or others who might know - the article mentions animal species with "two (or more) separate sexes". To which I responded "!?!?" What species are being referred to here?

Wikipedia lists a few
http://en.wikipedia.org/wiki/Sex

Also I found this:
http://biology.plosjournals.org/perlserv/?request=get-document&doi=10.1…

Skimming through the article I discovered this:

(A) Streaks of sperm (St) received after a mating interaction in the hermaphroditic flatworm, Pseudobiceros bedfordi. (B) Received sperm appears to "burn" holes (H) in the receiver. Some (unknown) component of the ejaculate dissolves the skin tissue.

I wouldn't like to be one of those guys

I'm probably being a bit simple, but can somebody tell me how to do that trick where you can put the link on a single word or phrase rather than having to paste the whole address?

I like the left handededness comparison. I am left-handed, and so is my father. When I played softball, I threw left-handed, but batted right-handed. Why? My father's brother, a right-handed individual, taught my father to bat right- handed. My father taught me the same way, and even if I have left-handed children, I will have to teach them to bat right-handed. So there is definitely somewhat of a combination of learned and inherited behavior.

Hipple, Rev. Paul T.,

You are the perfect example of what is wrong with your religion.

You have been given documented evidence that discredits Cameron, and yet because you saw him once, several years ago, and he told you they were lies and that there is a conspiracy against him, you believe him above all else. Because you are the perfect judge of integrity, and a conspiracy makes more sense to you.

You're not a child anymore. People WILL lie to your face while smiling. You have the tools to verify the things people say, but your blinders are getting in the way.

There are many other studies (reputable ones Rev Hipple) that examine the biological roots of sexual orientation. I have extensive links and some analysis on my website.

Matthew in #31, Dr. Cameron put it this way: When a man's protoplasm mixes with that of a woman, what wonderful thing can happen? But when a man mixes his protoplasm with another man, nothing can happen. It should be obvious from this that it just is Not Natural and so it Only serves the purpose of fornication, whereas when a man and woman fornicate, a miracle is always a possibility.

I feel very out of my place here and am unused to this persecution and feel I have become an unwitting distraction to your professional conversation. It is a bit like y'all coming to my church during services and talking about darwinism.

I do not wish to get further involved in this discussion with you gentlemen any further and wish you a good day and pray that you treat your wives better when you get home than you have treated me.

Thanks for the links, Andrew G. So it seems they're talking about genetic sex rather than morphology (i.e. the clam shrimp, with two kinds of female and one male), though the article about the harvester ants is certainly interesting.

I'll take a chance at being disemvoweled. I'll try one comment--with a promise of not responding to any that might get directed at me, only because I find Rev. Hipple's comments disturbing.

Rev Hipple, suppose Augustine and Pelagius adressed this topic in their great debate. Both, we can assume, considered homosexual behavior sinful (which is not the point.) Pelagius would, consistent with his theology, argue that homosexuals choose their orientation, because, according to Pelagius, we all are born neutral.

Augustine would argue the other way, for he believed that people were born with all sorts of predispositions.

So keep in mind that you, and all my fellow Christians who insist that homosexuals are not born gay, are making an overtly Pelagian argument. And remember that Pelagianism has repeatedly been declared a heresy, while Augustine's view has been embraced as orthodoxy.

Andrew, hyperlink syntax is here.

By Tukla in Iowa (not verified) on 10 Aug 2007 #permalink

Shorter Rev Hipple:

"You guys are mean! Gays are gross! I can't argue so I'll just run away!"

Sheesh. Since when was asking for *VALID* references "persecution"?

It is a bit like y'all coming to my church during services and talking about darwinism.

Which never happens, hint hint.

By Tukla in Iowa (not verified) on 10 Aug 2007 #permalink

My only problem is seeing beyond their sexual orientaion to their character.

For me, that's the crux of the matter.

It's not homosexuality that bothers me... it's the FLAUNTING of homosexuality that bothers me. And it doesn't really bother me any more than the flaunting of heterosexuality.

Anyone who runs around defining their existence in a public way by flaunting their sexuality make me feel uncomfortable. In essence, I don't care what you do behind closed doors. I don't want to hear about your conquests, and I certainly don't want to see the conquest taking place. And if you choose to publicly show off your sexuality, I think you have also chosen to accept public commentary, both positive and negative.

So if you and your partner want to walk down the street holding hands, cool... it's subtle, inoffensive. If you and your partner want to sit on the bench in a shopping mall sucking face and manipulating each other's genitals, well, that's disgusting whether it's two men, two women, or a man and a woman, and you should expect to be told so.

He told me about a horrible rumor spread on the interweb by his detractors who disagreed with his scientific conclusions, and that was not unusual in his scientific field.

First, did you really type "interweb" non-ironically? Don't do that.

Assuming you are sincere, you have been misled. Dr. Cameron's "professional difficulties" are not at all usual.

If you genuinely are a pastor of some sort, I can perhaps understand where you might assume "horrible rumors" means implications of some personal indiscretion. That's usually the context in which a pastor would encounter "professional difficulties."

To give a closer comparison of the sort of behavior that led to Cameron's difficulties, imagine if the Southern Baptist Convention heard of one of their member pastors preaching that Jesus never died for people's sins, and that they were all going to Hell, unless they spent ten minutes every morning clucking like a chicken. This hypothetical pastor claims to have gotten his information from the Bible, but is vague about exactly where, and claims persecution when challenged on it. The SBC might quite rightly want to remove this man from the rolls and publicly distance themselves from actions that in no way conform to the expected standard of professional performance among their members.

Now of course one wouldn't usually expect that sort of thing to happen among pastors. It isn't all that common among scientists either, but that's the sort of thing Cameron did with regard to the practice of research psychology. It isn't a "horrible rumor" when his unprofessionalism is something he himself proclaims as virtue. Making unsubstantiated claims that support a personal political agenda (like "most gay people were molested as children") and failing to back them up, while intentionally distorting the research conclusions of his peers to offer false support to those claims is simply unacceptable practice within his chosen field.

Cameron may be as personally nice and humble as anybody, but he's among the very worst of research psychologists. It takes more than a professional disagreement over conclusions to be thrown out of every professional organization you've ever belonged to.

Hipple, Rev. Paul T.:

For one thing many of the folks here are women, and may find it offensive that you refer to the people posting here as 'gentlemen'. For another, you assume such gentlemen have 'wives' automatically discriminating against those who have domestic partner arrangements (or something even looser).

You, sir, are a narrow minded bigot, who does not even do the courtesy of reviewing evidence. I have seen you post here a number of times, always with seemingly innocuous comments but always with an intemperate perspective. I can only hope that you are a parody. If you are real, I worry for the sanity of your 'flock' - if you truly are a reverend, *they* must have fallen out of the stupid tree.

Quoting your bible does not constitute a cogent argument. We do not accept the veracity of the source, so such citations are worthless - except from a historical perspective.

Why do people forget that it just takes a single gene in Drosophila to turn them into displaying homosexual behavior....
Posted by: kim

Maybe because it's not particularly relevant. There's a single gene on Drosophilia that causes them to grow an extra set of wings as well.

The analogy to human behavior simply isn't there.

I favor the nature/nurture approach and find it truly interesting that my own orientation is so variable. I honestly do not understand -- because I don't inhabit that headspace -- how anyone can remain solely attracted to one gender only, at all times and in all circumstances.

Oh well. De gustibus non disputandem est.

Dr. Cameron spoke at my church several years ago. He is a good Christian gentleman and was very persuasive.

So, being a liar and a bigot is what it takes to be a good Christian gentleman?

I don't think people should respond to Rev. Hipple's comments seriously. I think he's a satirist of the "Baptists for Brownback" type. Take a look at his website and I think you'll agree. I'm sure there are plenty of idiots who would agree with his views, but I don't think any of them are commenting here today.

I do not wish to get further involved in this discussion with you gentlemen any further and wish you a good day and pray that you treat your wives better when you get home than you have treated me.

Well, if my wife* refrains from making baseless generalistic accusations of child abuse, defending the expertise of cranks and liars, and making bogus claims of persecution, I think it will not be difficult for me to treat her better than you have been treated.

It's easier to speak to an audience than it is to speak to a flock, is it not?

* I don't actually have a wife, but I wouldn't mind...

By valhar2000 (not verified) on 10 Aug 2007 #permalink

"Rev. Hipple" runs the "Dominionists for Tancredo" website PZ mentions in his recent post. That website is clearly a parody. "Rev. Hipple" is just pushing buttons here, presumably for his/her/their own entertainment. Don't take the proposed arguments seriously.

Perhaps I should be happy that so soon after commenting that religion was the problem here the Rev Hipple pops up. Possibly divine providence sent him to prove me right. I'd still rather be wrong though.

Thanks, Tukla

I think the Rev Hipple has gone back into his closet.

I do wonder at the mindset of anyone (religious or not)who believes they have a right to impose their views on the personal lives of other folk.

Treat others as you wish to be treated, unless you're a masochist, that's what I say.

By Scrofulum (not verified) on 10 Aug 2007 #permalink

how anyone can remain solely attracted to one gender only, at all times and in all circumstances.

You'd be amazed how easy it is for some of us...

I have sometimes wondered if and how much my own condition colours by perception fo this issue. I have never had any doubt that women are attractive and men are not, so it seemed perfectly natural to me that people of other orientations might have a similar experience. Alas, it seems not to be so.

By valhar2000 (not verified) on 10 Aug 2007 #permalink

NickM

I don't think people should respond to Rev. Hipple's comments seriously. I think he's a satirist of the "Baptists for Brownback" type.

Sort of leaning in that direction myself, honestly, without having looked at his site. The likelihood of someone genuinely that pollyannaish stumbling in here by chance is pretty low, and, seriously, "interweb?" I honestly took a chance he might be for real simply because if he's a troll, he's actually not a very skilled one. I can spare him a single reply. Pretty much done now either way.

Given one twin who is gay and left-handed, the other twin is more likely to be gay than left-handed.

Gelf - I like to see a good-old-fashioned Pharyngula-style fundie-stompin' as much as the next heathen, but I actually started to feel guilty watching people respond to that guy seriously while knowing (pretty much) he was one of those new-fangled parody trolls.

I do not wish to get further involved in this discussion with you gentlemen any further and wish you a good day and pray that you treat your wives better when you get home than you have treated me.

Sounds like your typical latent homosexual Christian preacher.

Though I'm hard-pressed to think of a species off the top of my head with all three occurring naturally...

Lots of fish species have all three occurring naturally in various combinations of space and time. (If you study reproductive biology, mammals look positively vanilla in comparison to fish.)

I don't want to spoil a fun children's film, so let's just say that Finding Nemo didn't tell the full story about clownfish.

so it seemed perfectly natural to me that people of other orientations might have a similar experience

No doubt some do, while others (like me) are baffled by what seems like an arbitrary distinction between male and female attractiveness. It's not that I deny such a distinction exists and can be quite strong for many people; I just can't grasp it emotionally.

By Tukla in Iowa (not verified) on 10 Aug 2007 #permalink

So, Hipple is most likely a parody troll huh? I feel used...

Tukla, that's generally the case with emotions that one lacks oneself. By the same token, I can't emotionally grasp what it's like to be attracted to a man, to the extent that I sometimes marvel that women are. ;) (Not a boast- in fact I think of it as a limitation, but one I seem to be stuck with.)

By Steve LaBonne (not verified) on 10 Aug 2007 #permalink

What if we are born with an orientation, AND we can make a 'choice' about it?

For example, some people are born with 'indeterminate' sexual organs.

If orientation is a grayscale from "extremely heterosexual" to "extremely homosexual", then there are a lot of people who will likely never change their minds- at either end of the scale.

That leaves the people in the middle of the grayscale- a wide swath of 'indeterminate' orientation.

Those who end up there may, perhaps, have the 'option' to change their minds about their orientation- given that they will likely default to heterosexual as this is what society suggests.

The truth is, who cares? ...the people who have a problem with their own sexuality, usually. They need to get over it. The 'truth' of sexual orientation may or may not be discovered, proven, but we will go on mostly ignoring it in everyday life anyway.

By Will Von Wizzlepig (not verified) on 10 Aug 2007 #permalink

Pablo, the condition you describe is called cross- or mixed-dominance. I write and hold a fork--but not chopsticks, for some reason--with my left hand, but am generally orthodox (as opposed to southpaw) in sports.

(I'm also generally a poor athlete, but that's only because I was preyed upon by an older couch potato when I was young.)

re Hipple:

I feel used.

No doubt some do, while others (like me) are baffled by what seems like an arbitrary distinction between male and female attractiveness. It's not that I deny such a distinction exists and can be quite strong for many people; I just can't grasp it emotionally.

It really is funny how much variety exists here. As a (very?) straight woman, I find it much easier to understand attraction to a particular gender than attraction somewhat irrespective of gender, as you seem to be describing it. I have no doubt that a lot of people experience things as you do; I just have no point of reference. After all, the very thing that makes men attractive to me is their man-ness. As in, not women. So, it's difficult for me to mentally construct a model of "attractiveness" that doesn't take this into account either positively or negatively. I wouldn't know who to be attracted to anymore!

Of course, that's just me. As I said, I just find the variety of human experience in this regard to be quite interesting.

My father was born in 1916 in the US and was lefthanded. In school, his condition was treated as a deliberate act of rebelliousness and he was punished for it. They even tied his left hand behind his back so that he would learn to write with his right hand. And he did learn, and well. He could write legibly left or right. (And, no, his 'hands' were not the same -- which made him laugh at the idea of handwriting analysis revealing character.)

As to developmental causation, consider that freemartins have been known about since cows were first domesticated. The condition cannot be genetic, even the ancients knew that (although they though of the bloods mixing, not DNA). The cause, known for millennia, is in-utero masculinization due to the male twin. Practically everybody in farm country knows what freemartins are, and the cause, yet it seems that country folk are more inclined to demonize homosexuality in humans than city folk.

kmarissa wrote:
"I wouldn't know who to be attracted to anymore!"

Kinda fun when no one's off limits!

By Mrs. Peach (not verified) on 10 Aug 2007 #permalink

"Just as Male and Female are extremes ends of a spectrum (note nipples on men, structural homologs of penis and clitoris) so too, I expect, Gay and Straight are extremes of a spectrum. In both spectra there are some scattered throughout the middle. Black and White are just shades of Gray."
If so you might expect a normal distribution curve with the majority in the middle. I would be extremely surprised if this were the case. I would rpedict a bimodal distribution with hetrosexual being the much larger curve, gays being a smaller one and some mixing at the low part between the two curves.

I've been meaning to check the sources, but in the book Sperm Wars by Robin Baker states there have been studies showing that bisexuality can be seen as a reproductive strategy, and that homosexuality is probably an extreme of that.

By Stevie Rox (not verified) on 10 Aug 2007 #permalink

After all, the very thing that makes men attractive to me is their man-ness.

One misconception I've come across (not saying that you're expressing it, but I've seen it elsewhere) is that I must have only a single "type"-- that since I'm attracted to both men and women, I must be attracted to a sort of in-between androgynous sort of person, but that's really not true. I actually have two quite different "models" in my head, and I don't doubt that many straight men and women could relate to my models. They just don't have both in their head at the same time like I do.

In the end, I think it's important that we try to understand each other's point of view, even if we can't actually grasp them on an emotional level. It's a very touchy subject and easy to offend people, so I do my best to explain that my inability to relate to the point of view of someone like you with a strong preference doesn't mean that I think there's something wrong with it. I've gotten enough hate from both ends of the sexuality spectrum; I have no interest in responding in kind.

By Tukla in Iowa (not verified) on 10 Aug 2007 #permalink

jenni @30-

Please do not do your children the same disservice. A speedy lefty has a few feet advantage in beating out an infield single. I tried my hardest to learn how to swing from the left side when I was a kid, and could never get it right. I wish I had started earlier.

If anything, teach them to switch-hit. Batting effectively from both sides of the plate can be a nice advantage at the competetive level.

By povertyrich (not verified) on 10 Aug 2007 #permalink

It's not homosexuality that bothers me... it's the FLAUNTING of homosexuality that bothers me. And it doesn't really bother me any more than the flaunting of heterosexuality. (#39)

I was ready to tear you a new one, squid, then reread your comment and an willing to consider you simply have a huge blind spot or are unaware that saying a gay man is "flaunting" his sexuality is like telling an African-American he's being "uppity." Regardless of whether it's true, there's too much history there for it to be taken in any way other than as a deliberate, provocative insult.

Putting aside your own measure of groping in public places, which I'll cede as broadly valid, describing a homosexual as "flaunting" is a coded word that means "not pretending to be straight." The homosexual standard for "flaunting" is existing. The heterosexual standard for "flaunting" is usually somewhere around actually having sex in a public place, and even that most commonly results in an admonishment to get a room, not arrest, assault, or murder.

I had the same reaction, Usagi. I didn't say anything because I couldn't find the right words, so thank you for yours.

By Tukla in Iowa (not verified) on 10 Aug 2007 #permalink

Now, here's some outrageous tyranny to flame!

jenni (#30):

My father taught me the same way, and even if I have left-handed children, I will have to teach them to bat right-handed.

You will? Why? As the exclusively right-handed offspring of an exclusively left-handed baseball/softball fanatic, I had no trouble learning to hit from my natural side of the plate. The teaching technique isn't difficult--you just refer to "back elbow," "front hip," etc., rather than "right elbow," "left hip," and so on.

Heck, who wouldn't want to hit left-handed? You're closer to first base, bunting is easier, and--especially in youth and low-amateur-adult leagues--defensive players on the right side (the pull side for lefty batters) are generally weaker than those on the left side.

Down with side-of-the-plate indoctrination of children!!!!eleven!!

Damn--beaten by sixteen minutes by povertyrich.

At least my response was surlier.

I actually have two quite different "models" in my head, and I don't doubt that many straight men and women could relate to my models.

In all honesty, I don't think I actually thought about what the people you were attracted to were like in that regard. Seemed a bit impolite, imagining the sex life of a stranger ;) I'm not surprised that people would think you were attracted to androgyny, for precisely the reason you mention above. I think most people just don't realize that orientations like yours actually exist.

For my comment, I just meant that whatever internal framework determines where a person rates in attractiveness is inextricably linked to gender for me (and I imagine for most people? I may be wrong). I think you understand what I meant based on your reply. It's not only that men or women like me don't have both in our heads at the same time (although of course there is that); it's additionally that each of the two "models" would actually define the other model as unattractive based on criteria in the first model. But maybe, now, I'm just getting too confusing.

I wish I could say that I was surprised that you've experienced this kind of hatred, but sadly, I'm not. Frankly, I do find it hard to understand why anyone would get so worked up about who someone else was attracted to. And no, I never thought that you meant anything negative about a "decidedly straight" or "decidedly gay" orientation rather than a "decidedly bi" orientation, and likewise I never meant anything negative about your orientation. I think it's interesting as a general subject, but beyond casual curiosity, I really don't care whether any given person is attracted to men, women, both, or FLDS Mormons.

But if the latter, please don't breed more.

Usagi (#69):

Putting aside [squid (#39)'s] own measure of groping in public places, which I'll cede as broadly valid, describing a homosexual as "flaunting" is a coded word that means "not pretending to be straight." The homosexual standard for "flaunting" is existing. The heterosexual standard for "flaunting" is usually somewhere around actually having sex in a public place, and even that most commonly results in an admonishment to get a room, not arrest, assault, or murder.

Some atheist blogger or another (I can't imagine who...) might point out that this same problem exists for atheists who are accused of being "militant" or "fundamentalist" in their (our) expression or outlook. The double standard described above is eerily familiar.

#16:

I don't really relate them on the same level as you do, but the outcome, for me, is basically the same.

We already established a wide open area of law for exemptions for what I see as basically an arbitrary choice, that is, religion. People are given 'religious' vouchers or waivers for things that are otherwise required by law.

So, what do we care if 'gayness' is genetic or not. We've already established that our laws can be circumvented, etc. by one arbitrary choice, why not another?

I realize the argument isn't quite along parallels, but I've never found the obsession with discovering that gayness is a choice to be that compelling. Even if it comes out that being gay is 100% a choice of people, I still don't think we should deny them rights to marriage. Just like we don't deny religion exemption.

By Brendan S (not verified) on 10 Aug 2007 #permalink

I had the same reaction, Usagi. I didn't say anything because I couldn't find the right words, so thank you for yours.

Thirded.

By Steve LaBonne (not verified) on 10 Aug 2007 #permalink

I think you understand what I meant based on your reply.

I think we understand each other pretty well. Which is why I'm not bringing out the tired "dogs and cats" analogy.

I think it's interesting as a general subject, but beyond casual curiosity, I really don't care whether any given person is attracted to men, women, both

Agreed for the most part. It does become a practical matter when flirting, though. ;-)

But yeah, I don't care who a person loves. I'm much more concerned by who they hate, especially when they try to encode that hate into law.

or FLDS Mormons. But if the latter, please don't breed more.

LOL!

Iowa may not be home of the most open-minded people, but I can think of much worse places to live

By Tukla in Iowa (not verified) on 10 Aug 2007 #permalink

Researchers has already shown quite clearly, people DO CHOOSE to become homosexual, and usually only after they have been preyed upon by older homosexuals.

Then people also choose to become heterosexual, usually after being preyed upon by older heterosexuals?

Try talking to actual gay people about their sexual self-discovery sometime. In many cases (thankfully not as much anymore now that society is slightly more understanding) they went through years of trying desperately to be attracted to the opposite gender, doing everything possible to be *normal*, and finally realizing that their preference was innate and couldn't be budged. Yeah, some choice. The way we treat homosexuals here, it's hard to believe that anyone would choose to be ostracized, ridiculed, thrown into a mental asylum, or dragged behind a truck until dead.

I'm amused by theists who declare that people all have homosexual attractions, but good Christians are the people who don't act on them and thereby "become gay". No, dear, if you are attracted to the same sex, you're gay. Maybe bisexual. Maybe that's it, that people who claim that people "choose" to be gay are bisexual and therefore do have the opportunity to choose sides. Otherwise it makes about as much sense to say that people choose to be gay as it does to say that people choose to be heterosexual.

1) Years ago, one of my teachers said that for sexual orientation, nature and nurture are "inextricably entwined," and that phrasing has stuck with me ever since as eminently sensible given the evidence we have at this point.

2) Cappy: I've never read that way of wording it before, and I might have to borrow it to go with "inextricably entwined." It rings.

Thalarctos (#55):

Lots of fish species have all three occurring naturally in various combinations of space and time. (If you study reproductive biology, mammals look positively vanilla in comparison to fish.)

I don't want to spoil a fun children's film, so let's just say that Finding Nemo didn't tell the full story about clownfish.

True. The killifish came to mind for me; hermaphrodites normally undergo obligate internal self-fertilization, but under certain circumstances the males can apparently mate with the "females" (immature hermaphrodites) and stir up the gene pool. I wasn't sure if sex changes counted as different sexes, though. ;-)

Gurf! (Only sound I can think of to express my frustration at the discussion/judgements on "bisexuality" -- the quotes give you some idea of my thoughts on the matter.)

People have sex. They have sex for different reasons, with different people, at different times in their lives. Adding more labels than that leads to demonizing people for their activities.

Is a man who is basically a complete slut, a "top" who takes the attitude "a hole is a hole" a bisexual? Or is he "something else"? Is a person who is heterosexual when out in society, yet moves easily to sex with the same gender while in prison a bisexual? What about a woman who loves "falling in love", and falls in love with both men and women? And what about the person who masturbates to images of goats -- while being married and a good parent? What do you call that? How about the millions of British public
schoolboys who went through adolescence jerking each other off, but who are now heterosexual-"normal"? (whatever that is)

Hormone-imprinting during prenatal development sets up baseline attractions for an individual; sexual experiences, positive and negative selectively reinforce chosen behaviours; our big brains and our imaginations allow us fuck an umbrella while imagining it is Nefertiti, Queen of Egypt, and we are the reincarnation of Jerry Lewis.

What consenting adults do with their sex lives, ESPECIALLY if it changes over time, is not a reflection of their character, except in a general sense (considerate lovers are more likely to be considerate people when out of bed, and vice versa).

As a gay man I have to defend Evolving Squid @ # 39. I wasn't offended at all. I took his/her definition of flaunting as pretty fair. Holding hands while walking down the street was explicitly defined as NOT FLAUNTING, but sucking face on the bench while groping definitely was flaunting. I can be happy being able to hold hands with my hubby, but I don't want to see anybody publicly groping. Actually that last part isn't quite true, but that's for another blog ;-)

Then people also choose to become heterosexual, usually after being preyed upon by older heterosexuals?

No, Carlie; haven't you read the homophobic literature out there? It's really quite simple. If you're molested by someone of the same sex, then you become attracted to the same sex and become gay. But if you're molested by someone of the opposite sex, you're driven away from the opposite sex and become gay.

Don't ask me how they reconcile these.

Since homosexual behaviors appear to have been with us forever, why does the judeo/christian/islamic tradition condemm (sort of) homosexual behavior? Do any other cultures have a similar prohibition? If so, why?

By other bill (not verified) on 10 Aug 2007 #permalink

rickels, evolving squid, do you consider a gay person putting a picture of their partner on their desk at work to be flaunting their homosexuality?

Don't ask me how they reconcile these.

You're assuming they try, or even notice the conflict.

By Tukla in Iowa (not verified) on 10 Aug 2007 #permalink

Other Bill: Judeo/christian/islamic tradition condemns homosexual behaviour only as a subset of their schemes for overall sexual/social control. Men who have wives and children are easier to control. Women (and often men) who are unfaithful heterosexually may be fined, imprisoned, tortured, or killed. It's all about external control -- someone else controlling who you have sex with, how you have sex, what you eat and when, what you do on certain days of the week, praying five times a day in a certain direction and on and on and on. What religion does is to internalize these controls, so that you police yourself, rather than the religious authorities having to make half the population guards of the other half.

Matthew in #31, Dr. Cameron put it this way: When a man's protoplasm mixes with that of a woman, what wonderful thing can happen? But when a man mixes his protoplasm with another man, nothing can happen. It should be obvious from this that it just is Not Natural and so it Only serves the purpose of fornication, whereas when a man and woman fornicate, a miracle is always a possibility.

1) Liver flukes are natural. Clothes aren't. So what?
2) Your argument begs the question because it assumes that the listener believes that sex for pleasure is a bad thing. This is a profoundly ignorant and misanthropic position to hold. You have my sympathy.
3) "Protoplasm" as a scientific concept has been discredited for, at a minimum, two thirds of the time you've been alive. Try reading something that isn't apologetics once in a while.

I feel very out of my place here and am unused to this persecutionand feel I have become an unwitting distraction to your professional conversation. It is a bit like y'all coming to my church during services and talking about darwinism.

1) Butting in to a real grown-up discussion with a hateful and infantile assertion tends to result in that feeling, yes. The question is, why did you feel the need to in the first place?
2) You seem to be a bit confused. Here is the definition of persecution. Here is the defintion of what you are being exposed to at the moment. Please learn the difference.
3) There's no such thing as "Darwinism." Evolution is not a religion or even an ideology.

I do not wish to get further involved in this discussion with you gentlemen any further and wish you a good day and pray that you treat your wives better when you get home than you have treated me.

I can only speak for myself here, but if my wife were to express a profoundly ignorant or bigoted opinion, I would attempt to reason with her about it, since I see her as a person and an equal. If she were generally prone to bigotry--or was as big a crybaby as you about her opinions being subjected to criticism--we probably would not have been married in the first place.

Incidentally, I find your assumption that everyone here is male and heterosexual patently offensive.

Aaron, hermaphrodites, or as they prefer intersexed, people do occur 'naturally'. I know at least one personally and I have corresponded with others.

Squid, as has been pointed out 'flaunting' is usually used to mean ANY show of affection toward your partner if you are gay or lesbian. It can get you beaten or killed all to easily.

To add to the confusion on sexual orientation I identify as pansexual. Not only am I attracted to and have had relationships with both men and women but am attracted to and have had relationships with other trans-gender and gendeer queer people. Yay for diversity!

other bill, some suspect the judeo/christian/islamic despite for homosexuality is a result of early competition with religions that featured homosexual temple prostitutes, such as the church of Adonis.

I should add: the other popular explanation for the judeo/xtian/islamic despite for homosexuality is that all are extremely sexist religions, and despise all things feminine. Making the Man, who was made in the Image Of God, play a feminine role is a terrible offense to these people.

Note to self: Don't talk about sex when stuck in the office for several more hours.

By Tukla in Iowa (not verified) on 10 Aug 2007 #permalink

Natasha (#90):

Aaron, hermaphrodites, or as they prefer intersexed, people do occur 'naturally'. I know at least one personally and I have corresponded with others.

Oh, I know there are intersexed people out there. I was referring not to the historical usage of the term, but rather to instances where "true" hermaphrodites make up a significant portion of the breeding population of a species (such as is the case with C. elegans, and with many flowering plants).

I've often wondered at the Xian penchant for homophobia - especially since they are the religion renowned for catamites through much of the dark ages & later, and there have always been 'situations' such as the most recent scandal involving the Catholic clergy -- why else would there be so many monasteries?

Other cultures have also sought 'boys' for the pleasure of the ruling classes.

The only rationale I could think of was related to hospitality: If you offer a man a female slave to bed - you'll end up with more mouths to feed. If you offer a boy - then you definitely have no ongoing liability (and may even be able to sell the boy!).

Per the other points: Personally - I have no problems with displays of affection, of any flavor, public or otherwise.

Something that caught my eye, previously, regarding "what has more than 2 sexes". The first thought that came to my mind was that of higher fungi (mushrooms). Many species of mushrooms require mycelial mixing from more than two spore-sources before they will "flower" and produce spores/seeds. This can easily be viewed as having more than 2 sexes, albeit analogously.

OK, ok, I'll admit here that I'm no expert, but I have read a bit on this subject. Also, keep in mind that the above process is not the only factor in many mushroom species' ability to flower. And, before someone asks :) yes, I (knowledge-wise) am capable of growing the "funny kind" of mushrooms. However, I'd make one whole heck of a lot more money if I could figure out a way to grow Morchella commercially.

My 2c.

By jeffox backtrollin' (not verified) on 10 Aug 2007 #permalink

Aaron, OK understood. Sorry if I was a little too touchy on the subject. As we have learned on this very informative thread there are fish populations that do have hermaphrodites making up a significant portion of the breeding population. Damn fish get all the fun *grumble*. On the other hand I don't have to worry about being eaten by a barracuda.

Although, speaking of rodents and their behaviors, if a female mouse does not have a vomeronasal organ (either from genetic deficiency or surgically removed), she will start to behave like a male.

http://www.bioedonline.org/news/news.cfm?art=3500

http://www.nature.com/nature/journal/vaop/ncurrent/abs/nature06089.html

Which probably does not have anything to do with humans, especially since the vomeronasal organ in humans is supposedly defunct.

Still:

"Instead of building a male brain and then a female brain, you build a mouse brain, and then there's a sensory switch that makes sure that the animal behaves appropriately according to its gender."

By Owlmirror (not verified) on 10 Aug 2007 #permalink

Holding hands while walking down the street was explicitly defined as NOT FLAUNTING, but sucking face on the bench while groping definitely was flaunting.

Right, but I disagree that you should "expect" to be admonished for it. Let's say that I sit on that bench at the mall chewing a hot dog with my mouth open. Maybe not the prettiest sight, but anyone who comes up and tells me "not to flaunt my eating habits in the open" is still a twerp.

And in this regard, what's the difference between sucking face and sucking a milkshake? Both produce sucky noises that are extremely annoying to outsiders, but I don't see much reason to get "disturbed" by either.

windy:as a follow on -- I actually *like* to see people 'necking' in public - it makes me smile to think people can be so publicly & passionately affectionate to each other.

My wife & I have been together too long... passion needs a while to get going!

Really now, who wants to live in a world where one (er... two?) can't have a cosy little make-out session on a bench in a particularly romantic setting? I'm with Tony--makes me smile. Especially the old couples.

he said interweb, he's a troll.

Usagi, Natasha, thalarctos, and others:

First, I note that Evolving Squid used the term "flaunting" more or less correctly according to its actual definition. Second, aside from his using a term that has acquired an emotionally loaded connotation, is there anything objectionable about his sentiments?

(They strike me as prudish, I'll admit, but...)

is there anything objectionable about his sentiments?(They strike me as prudish, I'll admit, but...)

Prudish, definitely. More, I don't know*, because while he's said there's a boundary somewhere, he hasn't made it clear where that is. I'm curious where he draws it, so I'm asking a more specific question.

* but the aggressiveness of making an apologia for confronting people over kissing in public doesn't seem like a good sign. Even if we stipulate (just for a moment, because I don't think it's at all a given) that public kissing is rude, does he, like the other commentors asked, go after people who chew with their mouths open in public, too?

At a first approximation, his comment made him sound like a real hair-trigger jerk, which is why I asked for more info--to see whether and how that first impression held up.

I don't want to spoil a fun children's film, so let's just say that Finding Nemo didn't tell the full story about clownfish.

You mean some go down the drain, others get caught in the net, while still others get sucked up the filter?

does he [...] go after people who chew with their mouths open in public [...] ?

Can we define "in public" as meaning "anywhere within the range of Kseniya's sight or hearing" please?

when a man and woman fornicate, a miracle is always a possibility.

Sexual reproduction, one of the most common biological events in earth's history, is a miracle? Geez. That's like grade inflation in higher education. I wonder what other common events that involve body fluids now qualify as miracles...

I wonder what other common events that involve body fluids now qualify as miracles...

Those that are followed by a "Bless you!", obviously.

As a gay man I have to defend Evolving Squid @ # 39. I wasn't offended at all. I took his/her definition of flaunting as pretty fair. (#82)

I refrained from bashing Evolving Squid and opted for explanation because I assumed malice wasn't intended. Regardless of how "flaunting" is defined or any individual reacts to it, the historic use makes the term insulting in this context (and I can't tell you how grateful I am that the topic of the post is sexual orientation, not "sexual preference"). That the insult was unintentional or qualified by an alternate use can not change this. Saying you admire Hank Aaron but think Barry Bonds is "uppity" can only carry racist meaning no matter how the rest of the sentence is parsed.

rickles, I'm going to hazard a guess you're not "of a certain age." I had similar discussions with my first boyfriend in the late 80s as queer was being "reclaimed." He's never been able to accept the use of queer as anything other than an epithet. It's a generational thing. That flaunting doesn't have weight with you that it does with me, Tukla, and Steve both encourages and horrifies me. Encourages because you accept that Squid's discussion is (or should) be about appropriate behavior in public venues (which can be done without resorting either to loaded words or reference to the sexual orientation of participants); horrifies because whether you realize it or not there are plenty of places where this dog whistle language is still very much in use and it can be downright dangerous not to be able to decode it. [/getoffmylawnyoudarnkids]

Re: Flaunting.

I think E-Squid was pretty consistent within the comment, but I do wonder if he'd admit that he finds homosexual flaunting to be subjectively more "in your face" than otherwise identical heterosexual flaunting.

I don't think a "yes" answer would damn him in any particular way, for I also do not think it would be unreasonable to speculate that a majority of adults would concur - but not necessarily out of any bias, but merely because any display of romantic affection between same-sex couples is less common and more surprising than the same display between hetero couples. (Less common by sheer weight of numbers, but more surprising because the average American just isn't used to seeing openly gay couples being affectionate with each other in public!)

If this is true, and I think it is, I might then consider making a case for the (temporary) social value of moderate homosexual flaunting. There's an analogy here with outspoken atheism. Both acts make a declaration, which goes something like this: "We are no longer afraid to publically display this aspect of ourselves which for millenia has been demonized, pathologized, criminalized and suppressed." The benefit? Desensitization to, and consequential acceptance of, the reality and inevitability of homosexuality and atheism. And I do mean acceptance, not tolerance. When people begin to truly accept the differences between themselves and others, the harmful baggage that initially accompanies those differences starts to melt away.

Maybe there's another analog with the old "Black is Beautiful" movement of the 60's. I figure that was a sort of flaunting of blackness to promote awareness and acceptance of blackness as a non-negative attribute. That was way before my time, though, and I may not really understand what was going on with that.

I dunno. What do you guys think?

Hmm, I sense that Usagi may be justifiably impatient with my idea... :-/

Oh well. I'm just tossing it out there for discussion. Discuss! :-)

"Saying you admire Hank Aaron but think Barry Bonds is "uppity" can only carry racist meaning no matter how the rest of the sentence is parsed."

Er...except that they're both black, so I don't quite catch your meaning.

I think the point was that "uppity" has a certain connotation all by itself regardless of context, and that "flaunting" is the same way.
I'm inclined to agree - when I see the word "flaunting", the undertone I infer is that the person is showing off something in an assholeish way designed to bother others. Maybe it's just that I've never seen other usage of it, but I can't conceive a way to parse "flaunting" as being something other than implying that what's being done is obnoxious to the observer.

Speaking of homosexuality, what is this stuff on Hipple's site about inviting 10 to 14 year old boys to get involved in the Tancredo campaign by taking off their shirts??? I don't care what goes on between consenting adults, as long as any consenting my husband does is with me. But that stuff about the boys gives me the creeps. Anybody else have that reaction?

By hoary puccoon (not verified) on 10 Aug 2007 #permalink

One way of producing homosexual sons that has been reported by more than one study is having several sons. The greater the number of sons, the greater the probability of a gay son. The only speculation I have read is that the mother may be producing an increasing immunological reaction to each subsequent son.

Mitt Romney has five sons. Does anyone know anything about the sexual orientation of his youngest sons? Having a lot of sons does not guarantee a gay son, it apparently just increases the chances. So I'm curious. I find it ironic that Mormons could be producing more gays than any other sub-population in the US today. Type "gay Mormon" into Google. You will get two million hits; more than any other group I found except for gay muslims, another large-family culture. H-mmmmmmmmm.

That explains the whole Six Brides for Seven Brothers phenomenon.

Rey, Carlie is too gracious to spell it out, but I'm not: The word "uppity" has a very unfortunate history, having been irreparably marred by racist usage over a period of some decades. Calling Bonds "uppity" has serious racist overtones no matter what kind of praise is subsequently heaped on Henry Aaron.

Re miracle in procreation: I was suddenly reminded of my seventh standard biology teacher (that was a long, long time ago!), who once told us in class, while talking about the biology of sexual reproduction, that sexual reproduction - followed by the birth of a baby - was the most beautiful of nature's miracles.

He explained that out of about 30 million viable spermatozoa, one will penetrate the ovum, and immediately biochemical processes in the ovum will prevent the entry of another one. The fertilized ovum will travel through the fallopian tube, get implanted, divide and grow into the embryo, be nourished and immunologically protected through the placenta, grow and finally be born at term. At any stage in this entire process, there are several possibilities that something may go wrong, and it does - the evidence for which resides amply in the history of medicine. However, the process often culminates in a live birth, a process that - he made a point to mention - involves beating seemingly astonishing odds.

I remember him mentioning that in multicellular organisms, over a long period of time, the body, along with its physiological processes, has adjusted itself to maximize the efficiency of the procreative process.

He had a rapturous look on his face when he explained this, and it impressed greatly this (ex-) seventh standarder. No, he was not Christian, and there was absolutely no mention of any "intelligent design". In retrospect, I think that look on his face expressed an amazement he felt for creation of life, and perhaps I understand what he meant by a miracle - in the sense of an extremely outstanding or unusual event, thing, or accomplishment.

But I agree that 'miracle' is a very contentious word, particularly because of its so-called 'divine' connotations.

By Kausik Datta (not verified) on 10 Aug 2007 #permalink

From #19

"Question for PZ or others who might know - the article mentions animal species with "two (or more) separate sexes". To which I responded "!?!?" What species are being referred to here?"

I can't remember exactly , but I know there is a lizard species with 3 or 4 genders.

By Former PZ Student (not verified) on 10 Aug 2007 #permalink

To everyone arguing about EvolvingSquid: the stupid thing about his/her comments, regardless of whether you think it's okay to use the word 'flaunting' (even though that does connotate homophobia) is that s/he felt the need to mention when s/he thinks being gay is okay when commenting on a post that had nothing to do with how much gay people might 'flaunt' their sexuality. If you're truly not homophobic, which i doubt of this commenter, you would realize that your disgust at some people making out too passionately should have nothing to do with gays or biological origins of sexual orientation.

PZ Myers: ... perhaps the lability of sexual orientation in humans is a side-effect of unshackling sexual behavior from tight cyclic hormonal regulation. Freeing us from the bonds of the spring rut or the monthly estrus means human brains aren't quite as locked in to a single sexual stimulus.

Which begs, or at least politely requests, the question of just why humans have such nearly-flat reproductive-hormone cycles. Are there any other primates/mammals/species with sexual patterns so loosely bound to chronological dictates? Does this provide any sort of evolutionary advantage, or if not, what influences produced it as a side effect? Does one sex gain or lose more than the other as a result of this anomaly?

This query is not (just) an idle tangent: I would be profoundly grateful to anyone who might steer me toward (layperson-comprehensible) writings on this topic.

By Pierce R. Butler (not verified) on 10 Aug 2007 #permalink

Can I just say something really obvious?

The notion that some people are born homosexual (or bisexual, 73% hetereosexual, or whatever) and never change is (a) only about 150 years old and (b) in conflict with what little evidence there is.

If we accept the idea that people have an orientation, then we have to accept that it changes over time - and not just in the first quarter of life. There are so many forms of sexualities, and people adopt, drop and modify them so much, that the notion of a fixed "core" orientation is difficult to defend.

If there is an orientation, determined before or during puberty - or maybe before birth - then it is greatly offset, sometimes entirely masked, but such factors as available sexual outlets, social pressure, experimentation, and probably most importantly, developing personal taste.

I think E-Squid was pretty consistent within the comment, but I do wonder if he'd admit that he finds homosexual flaunting to be subjectively more "in your face" than otherwise identical heterosexual flaunting.

No, I would not admit that because I do not consider it to be subjectively more "in your face".

Evolving Squid:

You have my sympathies; I am, unfortunately, starting to recognize this pattern. You made the mistake of pushing one or two buttons and now every single thing you say will be filtered through a layer of preconception thick enough to stop an artillery round. I wish I didn't feel compelled to watch; it saddens me that other mostly-progressives would descend to this level, but if this is anything like the handful of times a person has taken issue with a minor point of a statement by an outspoken female blogger and been tied up and painted as a card-carrying member of the "keep 'em barefoot, pregnant, and in the kitchen...now make me a sandwich, bitch!" club regardless of their actual statements (see certain comments here, here, and especially that thing with DailyKos' ill-considered and insensitive comments about Kathy Sierra), you might as well stop posting; so many words are about to be shoved in your mouth that those shoving them will be able to hold up both sides of the conversation all by themselves.

Pierce (#119):

Which begs, or at least politely requests, the question of just why humans have such nearly-flat reproductive-hormone cycles. Are there any other primates/mammals/species with sexual patterns so loosely bound to chronological dictates? Does this provide any sort of evolutionary advantage, or if not, what influences produced it as a side effect?

From what I understand, it's a direct result of having non-reproductive sex. Despite what the religious right might have you believe, people have sex for fun, not for children. If I could tell from sight that a potential sexual partner were at the height of her fertility, I would look for someone else, because I don't want my fun to have those kind of resource-draining consequences. It makes great sense from an evolutionary standpoint: the females who got pregnant most often were the ones who didn't show such prominent signs of fertility and were therefore prone to more "accidents."

Sorry you see it that way, Azkyroth, but those of us who are more s*x-positive** don't see any reason why anyone whose reaction to kissing in public is "that's disgusting", and escalating by accosting the kissers, should be surprised when (s)he is invited to a big heaping double serving of STFU.

The homophobic dog-whistle code word is just icing on the turd cake.

**PZ, your spam filter is totally asinine.

You mean some go down the drain, others get caught in the net, while still others get sucked up the filter?

(as Kseniya puts her finger on the reason thalarctos doesn't keep one of those microcosms of life and death called "aquarium" in her home...)

uh, no, Kseniya, that's not exactly what I meant, but since I like to keep my children's films and my discussions of sex totally hermetically compartmentalized from rach other, let's just say that in the absence of Nemo's mom, he and his dad would have come to an arrangement, and we'll leave it at that...

speaking of discussions of pervy fish sex, maybe ichthyic has some specific domain knowledge to add?

Azkyroth makes a good general point about the "pattern" he's addressing, but until Squid actually responds in a meaningful way there's nothing to "filter", so Azkyroth's point, though sound in principle, is kinda moot.

I admit I'm a little puzzled about why you, E-Squid, chose to respond to my (mostly rhetorical) question and only to that question, particularly in light of the fact that it wasn't even posed to put you on the spot. Quite the contrary - it was posed as the first step in making a point that even if you (or anyone else) happened to be pre-disposed to notice PDA between same-sex couples more so than between hetero couples, there's at least one pretty good reason for it that has nothing to do with "homophobia".

I imagine you read the first paragraph, stopped there, and fired off a terse response without first understanding that I was trying to let you off a hook that some other folk may have been looking to hang you on.

Well, whaddevah. I have not been injured here. Have you?

Point being, there are a least a couple of questions on the table that appear to be more pressing than the one I posed, and yet you've chosen to ignore them completely. Perhaps because you see what Azkyroth sees - but I urge you not to throw in the towel here, because it's my opinion that you, E-Squid, being the intelligent and well-spoken person that you are, would be best served in this situation by at least attempting to answer one or more of those questions, and seeing where that leads.

Anyway, E-Squid, regarding Azkyroth's comment, yes there's been much analysis of your word(s) and speculation about what you meant, but what better way to prevent people putting words in your mouth than to speak them yourself?

Maybe it's not that pervy, but I've always been amused by the sex lives of angler fish. The male is much tinier than the female, and unable to feed himself. He'll hunt for a female, latch onto her, and eventually his mouth fuses with her body (worst hickey ever), and he becomes little more than a parasitic sperm sack ready to do some spawnin' when the female's hormones say it's go-time. I guess when it comes to life in the abyss, Emile de Becque was right: "Once you have found her, never let her go."

The non-existence of Fish Morality implies the non-existence of a Fish God. Won't Dagon be surprised!

lol, Aaron--great example!

The non-existence of Fish Morality implies the non-existence of a Fish God.

It's not even non-existence of Fish Morality, it's anti-existence, at least from our point of view.. There's at least one species of fish in whom fertilization of the egg is triggered by the presence of sperm from another species of fish (not such a big obstacle in a liquid environment as it is on land). I'll have to find my repro bio notes to find the species name; I don't have them at hand.

So the fish sperm fertilizes the fish egg, but only after the sperm of the other species has made the egg receptive to it.

In other words: obligate bestiality for reproduction.

Wow. Geez. The last time I got dumped, everyone tried to console me by telling me that there were plenty of other fish in the sea. I had no idea what level of promiscuity was being suggested! I'm so naive sometimes.

Re: Angler fish. I guess the angler-dude winds up singing "You Light Up My Life" while the angler-chick sings "Bite Me". That rocks!

If people chose to become homosexuals after being preyed upon, why doesn't Re Hipple just pray for them to un-choose it? What's that Skippy? He does? And the prayers don't work? Because God doesm't exist, but there are kids are trapped down the mineshaft?

thalarctos:
1): I'm moderately certain that people more sex positive than me don't exist.
2): If your (plural) objection is to his squeamishness and alleged rude conduct with regard to public kissing, then talk about that instead of dogpiling on a poor choice of words in his initial post on the subject and ascribing all sorts of cardboard-cutout views to him in the process. You'll even find me agreeing with you.

Everyone:
I haven't kept with every thread where I've asked about this, but there have been many. Did PZ or the Seed Overlords or whoever's responsible ever explain why the "having problems commenting" page still does not warn users about the hair-trigger spam filter or identify which words or phrases trigger it--a list that apparently includes the proper spelling of "sex" now (seriously, WTF?)[Update, after several minutes of experimenting: apparently it's the hyphen after "sex" that's the problem. Do I even want to know? I'm rather glad it wasn't "sex" by itself; the logical next steps at that point would be blocking "is," "and," and "the".]

Question for PZ or others who might know - the article mentions animal species with "two (or more) separate sexes". To which I responded "!?!?" What species are being referred to here?

The white throated sparrow (Zonotrichia albicollis) has two morphs which have gender like properties. The white striped (WS) morph has higher levels of sex hormones in both male and females. WS females will sing and defend territory, and the WS males will try to drive them off instead of mating with them. The tan-striped (TS) morph is less aggressive, and TS females do not sing. WS males therefore mate preferentially with TS females. WS females are also more sexually aggressive, and solicit copulation from TS males more than TS females do from WS males. Because the WS male is so aggressive and spends less time guarding the nest, however, its mate is far more likely to copulate with other WS males, whereas TS male/WS female pairs tend to be monogamous.

In effect, white/tan is a parallel gender to male/female, so that mating occurs only with 1/4 of the species instead of 1/2.

There's at least one species of fish in whom fertilization of the egg is triggered by the presence of sperm from another species of fish

The Amazon molly Poecilia formosa is a gynogenetic, all female species that requires the sperm of a sister species only to start development. Poeciliopsis monacha-lucida are hybridogenetic and toss the paternal genome before reproduction. I haven't heard of fish that require sperm from another species to activate the eggs and then reproduce sexually, but anything is possible!

Pablo @3:

(in fact, from what I've heard, twin studies tend to find stronger correlations in homosexuality than in handedness)

Twin studies do, indeed, very strongly suggest that there is some genetic component to homosexuality (assuming one trusts twin studies). OTOH, other studies show a very strong correlation between male homosexuality and an environmental factor. It's not an environmental factor one could do much to alter, though: it's development in the womb of a woman who has already borne male children. It's a relatively strong predictor: the more older male siblings a male has, the likelier he is to be gay. (In absolute terms, of course, it's a quite weak predictor; but relatively speaking, it's stronger than almost anything else.)

As PZ says, it's both, and none. Personally, I find the genetic component of homosexuality (and there probably is one, thought we don't know how important it is) absolutely fascinating as a conundrum for evolutionary theory. What would explain its persistence: does it confer net gains to inclusive fitness via what we might call the "scrub jay effect"? Does the gene (or suite of genes) in question increase fecundity of females such that overall numbers of offspring are higher despite the decreased likelihood that male siblings who inherit the gene will reproduce? Who knows? It's all extremely interesting as a matter of biology. But (and here again I agree with PZ): it needs to be absolutely, utterly uninteresting when it comes to recognising and respecting the rights of individuals.

I've really wondered about that "previous siblings" correlation. Couldn't it just be that since homosexuality occurs at a rate of about 10% in the population anyway (that's the number I've heard), that just having more children makes it more probable that one of them will turn out to be gay?

Azkyroth

after several minutes of experimenting: apparently it's the hyphen after "sex" that's the problem. Do I even want to know?

My experiences with the filters here lead me to conclude that what the filter is more concerned with spam - specifically, URLs to porn sites - than with naughty words per se. Therefore it is more likely to snag an embedded or hyphenated word, particularly when enclosed in [a][/a] tags, than the isolated (space-delimited) word itself. Odd, yes, but there it is. (This behavior of the filter became apparent when I found I was unable to put "Neil DeGrasse Tyson" inside an [a] block.)

I've really wondered about that "previous siblings" correlation. Couldn't it just be that since homosexuality occurs at a rate of about 10% in the population anyway (that's the number I've heard), that just having more children makes it more probable that one of them will turn out to be gay?

No, men with older brothers are more likely to be homosexual. If there were no correlation, the older brothers should be as likely to be gay.

Yes, Windy's got it. Carlie, it's not that the probability of having a gay son in the family increases as the number of sons increases (which is pretty obviously going to be true if the probability of any son being gay is constant) it's that the probability of a son N being gay increases as N increases (that is, with the birth of each successive son, the odds of THAT SON being gay increases.)

It's sorta like the gambler's fallacy come true: Unlike in cards or dice, the probability of a given outcome for an event DOES depends on, or is influenced by, events that precede it.

Carlie @137:

Couldn't it just be that ... having more children makes it more probable that one of them will turn out to be gay?

It is indisputably true that (quite without regard to any putative biological effect) the more children one has, the greater the chance that at least one will be gay. But if aggregate number of offspring were the only factor at play here, we'd expect the gay children to be distributed randomly among the cohort of sibs. But from what I've read, it's not random: the later in the cohort one is born, the higher the chance of being gay.

And BTW, do note that all this relates only to males. The first-born son of a woman who had previously borne 15 girls is no likelier to be gay than a male only child. (It goes without saying that either or both of these boys could be gay nonetheless; quite clearly the putative influence of previous male siblings is no more dispositive than the putative genetic factor suggested by the twin studies.) I have never come across anything that suggests a girl is likelier to be gay if she was preceded in utero by either other girls or by boys. It's among girls, then, that I'd expect your hypothesis to be true: the more of them born to a given family, the greater the chance that (some random) one of them will be gay.

And now you must excuse me, for I must prepare for the arrival of a dear friend who will spend the night with us before flying to America. He is gay; and, as it happens, the youngest of three sons.

Oops, now that I think about it, I guess that's can be true for cards, too. The odds of drawing the Ace of Spades drops to zero if it's already in your hand! However, the odds of getting a good hand doesn't increase if your last five hands were crummy...

Pablo (#3) writes:

I've always thought that the comparison with left-handedness is pretty appropriate. I don't know if you can find a "left-handed gene," but no one would argue that handedness is learned, either ...

CBC Radio's Quirks and Quarks presents an interesting discussion with several scientists who are studying the genetic and learned basis of handedness.

Mrs. Tilton, considering how succinct and clear Wendy's comment was, the evidence suggests that the odds are very good that a fourth explanation would be even wordier, if written by a woman. :-D

That makes sense. I didn't realize that it was narrowed down to youngest son and with just the older brothers rather than also sisters. I do remember hearing about it a few months ago when Colbert took offense at it (he with something like 10 older siblings), but hadn't paid it that much attention.

1): I'm moderately certain that people more sex positive than me don't exist.

Previously I had gotten that impression of you, which is why I was so disappointed to see you defending the "gay panic" defense, and demonizing people who called Evolving Squid on it. I don't think that position is consistent with being sex positive (trying no hyphen).

2): If your (plural) objection is to his squeamishness and alleged rude conduct with regard to public kissing, then talk about that instead of dogpiling on a poor choice of words in his initial post on the subject and ascribing all sorts of cardboard-cutout views to him in the process. You'll even find me agreeing with you.

Then why all this demonization of "so-called progressives"?

In a nutshell, the gay panic defense is that the escalator of the situation perceives himself justified in initiating an attack where there previously was none on him, because the gay victim made him feel icky (or was "disgusting"). Evolving Squid said very clearly that someone doing something in public that makes him feel disgusting shouldn't be surprised if he or someone else escalates.

So if I'm kissing Mr. thalarctos on Alki Beach at sunset, and some freak walks up and starts yelling at us over it, you're on *his* side? Whatever.

Ok, so he's shown he's willing to escalate. He didn't say where he was willing to stop. If he calls us "disgusting" and we laugh at him and call him a repressed freak, does he continue to escalate? I don't know, since he has not weighed in on that issue, but I do know that a couple in that situation was shot and killed on Alki Beach a few years ago. So how do I know any particular escalation advocate is willing to escalate only so far and no farther?

Is our sitting in a car on lover's lane publicly disgusting, and you'd defend his tapping on our window to tell us so?

And that's just straight examples of where escalation is freaky. There's a plethora of gay-specific situations that he is vague on.

If a gay co-worker has a picture of his/her family on the desk, is that "flaunting"? Is the standard in the same place as for straight co-workers?

How about the existence of a bar called "The Man Hole" down the street from him? Is he justified in going in there and telling people they're disgusting?

Because he's declared he's willing to escalate, and he's saying the recipients of the escalation shouldn't be surprised when it happens, he's already started out on the gay panic defense. I'm just wondering how we know he escalates only to the level of words and no further.

And the point of the Hank Aaron/Barry Bonds analogy was that using some kind of "straight panic" defense in apposition doesn't take away from the fact that he's embarked on the gay panic path.

So we have someone who's:

1) essentially written an apologia for the gay panic defense;

2) added a new wrinkle to it, his "straight panic", as well;

3) chosen a code word that the homophobic right uses to very specific purposes.

Some people called him on the gay panic flat out, others decided to explore socratically to see how early the escalation starts and how far he's willing to take it. Yet, we're the ones you blanketly demonize. I just don't see how that's consistent with being sex positive.

Aaron (#124):

... it's a direct result of having non-reproductive sex. Despite what the religious right might have you believe, people have sex for fun, not for children.

I suspect this model may be backwards. Few if any other mammals have offspring in mind when they get romantic.

If I could tell from sight that a potential sexual partner were at the height of her fertility, I would look for someone else, because I don't want my fun to have those kind of resource-draining consequences. It makes great sense from an evolutionary standpoint: the females who got pregnant most often were the ones who didn't show such prominent signs of fertility and were therefore prone to more "accidents."

I doubt whether homo erectus, or even the early h. sapiens, had any more concept of the process of conception than did the average bonobo. With evolutionary questions, you need to start with the early end of the issue, and with the issue of concealed/reduced estrus, you need to focus on the females.

So: why did those of our great^X grandmothers who had less intense hormonal cycles fare better reproductively than those who retained the traditional "heat" patterns? The latter certainly would have not lacked for well-motivated partners...

By Pierce R. Butler (not verified) on 11 Aug 2007 #permalink

I did not think E-squid's comment was gay-panicky at all (only flower-hatty), but leandra raises a good point in #118:

If you're truly not homophobic, which i doubt of this commenter, you would realize that your disgust at some people making out too passionately should have nothing to do with gays or biological origins of sexual orientation.

why did those of our great^X grandmothers who had less intense hormonal cycles fare better reproductively than those who retained the traditional "heat" patterns? The latter certainly would have not lacked for well-motivated partners...

Perhaps they lacked in well-intended partners? (partners not willing to resort to infanticide, or more willing to support offspring, depending on the hypotheses.)

And I'm not sure what you meant by "flat reproductive hormone cycle", the lack of visible estrus? It might not correspond exactly to having lots of recreational sex, although they are most likely connected. Bonobos have not lost the estrus signals, they have extended them compared to chimpanzees.

This query is not (just) an idle tangent: I would be profoundly grateful to anyone who might steer me toward (layperson-comprehensible) writings on this topic.

Jared Diamond's Why is sex fun? seems like an obvious choice. It is now 10 years old so the scientific hypotheses might have evolved since then, but it could be a good place to start.

Windy (#150):

Perhaps they lacked in well-intended partners? (partners not willing to resort to infanticide, or more willing to support offspring, depending on the hypotheses.)

Maybe I'm misunderestimating our esteemed ancestors, but I still don't see how a reduced estrus would correlate with a higher level of paternal involvement.

And I'm not sure what you meant by "flat reproductive hormone cycle", the lack of visible estrus?

For a very crude first approximation, imagine a graph of estrogen & related hormones for females of a species with a pronounced "heat" cycle: the relevant curves would form a sine wave of rather high peaks and low troughs. Compare to a similar charting of human female hormones - the oscillations are still there, but relatively weakened. That's what I was trying to say by "nearly-flat reproductive-hormone cycles". (Given the nature of biochemistry in general, not to mention women in general, I have no doubt that real-world data would map out to something rather more complex than just a low amplitude sine wave. Even the public-health-education version of human female monthly cycle charting involves four different hormones, each with a distinct path.)

(Male) evolutionary psychologists offer spiels about the "loss" of estrus and "concealed ovulation" as signifying the human female is "always available", but all this tells me is that they must hang out at much hotter meeting places than those I've found.

My own impression is that this change in reproductive behavior must somehow correlate with the need for ever-increasing paternal assistance in raising young with longer periods of dependency - but just how the pieces fit together, and what the advantages were compared to the mainstream of less-committed primate family life, still seems mysterious.

Thanks for the Jared Diamond suggestion - I'll hunt for that on my next library trip.

By Pierce R. Butler (not verified) on 11 Aug 2007 #permalink

For a very crude first approximation, imagine a graph of estrogen & related hormones for females of a species with a pronounced "heat" cycle: the relevant curves would form a sine wave of rather high peaks and low troughs. Compare to a similar charting of human female hormones - the oscillations are still there, but relatively weakened.

Before speculating further, do we actually know that they are weakened? The relevant comparison here, IMO, would not be to any mammal, but to chimpanzee and bonobo hormonal levels, which I have no idea of.

Pierce (#148):

I suspect this model may be backwards. Few if any other mammals have offspring in mind when they get romantic.

I doubt whether homo erectus, or even the early h. sapiens, had any more concept of the process of conception than did the average bonobo.

Well there's the question, isn't it? Certainly most animals aren't consciously out to reproduce when they have sex. But if our ancestors were further inclined toward (and capable of) maximizing non-reproductive sex, then there would be evolutionary pressure to make the job harder for them.

I'm getting this from a lecture by Jonathan Marks (Department of Anthropology, UNC), by the way. The link lists some of his publications... I should probably check one or two out.

I did not think E-squid's comment was gay-panicky at all (only flower-hatty)

Yeah, as far as it goes, there's not really enough information to tell--the only difference is how far someone's willing to push an escalating situation, and E-squid didn't yield any insight into that.

There are already laws against public lewdness and child molestation, so I'm assuming we're talking only about things that the observer doesn't have the recourse of alerting security or the police to. I think we're just talking about individual judgments about what is "disgusting" and what's acceptable.

I think it's reasonable to assume that you don't surrender your expectation of safety just because you do something legal that someone else has a problem with. So if you're kissing in public, and someone decides to respond aggressively to you over that, then the question of whether they're just a bluenose or actively a basher depends on what happens next.

So you and your partner (gay or straight) are just minding your own business with a PDA (again, not public lewdness or anything, because there's legal recourse over that, just impolite), and someone gets up in your face over it. The situation has then gone from one with no aggression in it to a confrontation initiated by the viewer, based on some arbitrary individual standard of appropriateness.

Now that someone has gotten up in your face aggressively, you can respond by yielding, by escalating, or by defending yourself with an appropriate level of force. I think 1 is too much to expect of someone not doing anything illegal, and 3 is inappropriate under American self-defense law. So the question becomes what happens if you respond by defending yourself with an appropriate level of force, in this case something like laughing and calling the person who accosted you a jerk.

The salient question, I think, is what happens next: does the instigator leave it at that without further escalating, in which case he is only a bluenose (the best-case scenario), or does he take it to the next level of aggression (a basher)?

Neither is good; the only question is how bad is the situation? And I don't think having to determine between those options is an appropriate price for doing something legal (even if impolite) in public. It shifts the burden to the innocent parties, rather than to the individual with the arbitrary boundary.

And once we've established that, where does the display that the instigation begins to respond to occur? On a beach? In a parked car? In a moving bus? In the portrait on your desk at work? In a gay bar?

So I think that the only reasonable response to a legal, but tasteless, PDA, is that the viewer should mind their own business, grow up, move along, or any combination of the three.

But if our ancestors were further inclined toward (and capable of) maximizing non-reproductive sex, then there would be evolutionary pressure to make the job harder for them.

The "women were afraid of childbirth and started avoiding sex during ovulation" argument? Nonsense, if you ask me.
Some reasons
-it assumes a large part of what it tries to explain: that humans were already in the habit of having sex for fun all through the cycle. If human females had had a strict estrus, and wanted to avoid childbirth, it would have been much simpler to avoid all sex as much as they could (a losing strategy, of course)

-few modern humans are interested in avoiding giving birth altogether, even if pain relief is not available.

-babies confer status in most societies; girls would look to older females for information on childbirth, and what would they say? "It hurt, but it was worth it" or "never, ever have sex"?

-hunter-gatherer births are spaced by several years and they often resort to infanticide. Fertility seems not to be paramount in humans. If our ancestors were like that, it should not have been entirely detrimental for females to gain some control of their own reproductive rate (ie. if they had used their knowledge of ovulation to space births).

Windy (# 152):

... do we actually know that they are weakened?

Very good question. Maybe somebody knows; not me. It's safe to say the physiological & behavioral components of estrus are greatly reduced/averaged out: the extrapolation to hormonal causes is plausible, but sfaik not measured.

Windy (# 154):

....few modern humans are interested in avoiding giving birth altogether...

I don't have time to dig up stats on voluntary childlessness, but my impression (including 11 years of work in a Planned Parenthood affiliate) is that there are many people who are strongly motivated for just that.

Fertility seems not to be paramount in humans.

We, like elephants, whales, etc, are what are called "high-K" species, meaning that we have few offspring and invest heavily in their upbringing. Other high-K critters seems to do better at the de facto birth control required by this strategy; possibly if we'd spent another 100,000 generations as hunter-gatherers the lactation-as-ovulation-suppressant mechanism would be more reliable. This supports my idea that human sexual patterns involve (evolutionarily) recent innovations, including "flattened" estrous cycles, with a lot of rough edges remaining.

If our ancestors were like that, it should not have been entirely detrimental for females to gain some control of their own reproductive rate (ie. if they had used their knowledge of ovulation to space births).

I haven't seen any reports that anthropologists have found anything like the "rhythm method" in use in traditional societies. Abortion & infanticide, otoh, go way back.

Aaron (# 153):

But if our ancestors were further inclined toward (and capable of) maximizing non-reproductive sex, then there would be evolutionary pressure to make the job harder for them.

Probably so. Comparative studies with bonobo societies would also seem called for here. (Fwiw, John Hawks recently relayed an interesting report that bonobos in the wild show much less sexual activity than those in captivity.)

The whole question of "estrus" in human females, and corresponding reactions in males, is social nitroglycerin: I'm not surprised that researchers & serious academics seem to have avoided it (and relieved that sensationalists haven't made hay from it). Nonetheless, I suspect there are crucial psychological insights waiting to be uncovered here.

Those titles by Jonathan Marks look very interesting - thanks for another good lead!

By Pierce R. Butler (not verified) on 11 Aug 2007 #permalink

Previously I had gotten that impression of you, which is why I was so disappointed to see you defending the "gay panic" defense, and demonizing people who called Evolving Squid on it. I don't think that position is consistent with being sex positive (trying no hyphen).

Then why all this demonization of "so-called progressives"?

In a nutshell, the gay panic defense is that the escalator of the situation perceives himself justified in initiating an attack where there previously was none on him, because the gay victim made him feel icky (or was "disgusting"). Evolving Squid said very clearly that someone doing something in public that makes him feel disgusting shouldn't be surprised if he or someone else escalates.

The way I parsed his statement, he was expressing discomfort with public displays of heavy petting, and his inclination to express his disapproval--I reasonably assumed this would take the form of "get a room!" and a disgusted sigh and an eyeroll, or something to that effect. In retrospect, I can see why you might be worried about what exactly he meant or how far he would go, which hadn't occurred to me at the time. However, so far as I can see, the "gay panic" thing was essentially made up out of whole cloth by people who seized on the connotations of the word "flaunting," which he unwisely employed, and willingly allowed that kneejerk reaction to not only strongly color their interpretation of everything else he said, but to fill in things he didn't say, but that the stereotype they associated him with based on that word choice implied--and then hold him accountable for their interpolations. Regardless of what I think of the opinions actually expressed by the target of this behavior, such misrepresentation is strongly inconsistent with basic principles of truthfulness and fairness which I hold in extremely high regard, and as such I find it objectionable--all the more so from a group of people (progressives in general and pro-science progressives in particular, who constitute the major audience of this blog) who often pride themselves on "rationality", and especially so from a group of which I consider myself a member. Similarly, I find descriptions of atrocities by Americans under the Bush regime more upsetting than similar atrocities under third-world dictators; I'd like to think "we" are better than that, and I dislike being disappointed in that. I have observed a similar pattern with accusations of misogyny before, which is what I was referring to, and as such have already built up a backlog of disappointment with this behavior from those I consider my fellows.

I haven't seen any reports that anthropologists have found anything like the "rhythm method" in use in traditional societies. Abortion & infanticide, otoh, go way back.

Yep. I wasn't suggesting it was really used, but what I would expect if the "concealed ovulation evolved because conscious females stopped giving birth" hypothesis were true. Actually, an even more plausible outcome would be non-conscious females outbreeding the conscious ones ;)

...an even more plausible outcome would be non-conscious females outbreeding the conscious ones

For us high-K types, the key variable is not the number of pregnancies, but the number of offspring who survive long enough to reproduce themselves - in other words, who has the most grandchildren. Maybe somehow those females subject to periodic episodes of uncontrollable libido were thereby distracted enough to lose their mothering edge?

By Pierce R. Butler (not verified) on 12 Aug 2007 #permalink

Another possibility is that, since the female does not have an obvious fertile time, it's much harder for males to ensure they reproduce by going on their way after a single mating session at the opportune time, thus one would expect a selective pressure towards males who stuck around long enough to ensure that their partner was in fact pregnant; this would have the side effect of creating an opportunity for the male to help provide resources and protection for the female on an ongoing basis. Males who were more instinctively inclined to stick around might stay longer, continuing to provide those resources, which would allow the female to invest more energy in her actual pregnancies and, if the male stuck around longer than the duration of the pregnancy, in caring for their offspring, since the male's assistance would reduce the amount of energy she needed to invest in resource gathering and defending herself or fleeing predators. One would expect that this higher rate of energy investment would tend to result in more surviving offspring, hence the genes of males who were instinctively inclined to stick around, and women who were genetically disposed to invest more energy in their pregnancies and rearing of young offspring than in constantly foraging for themselves, would be more likely to be passed on.

Unfortunately, the problem with speculating in this vein is that far too many idiots will read the above, forget it's just a hypothesis, forget that the environmental and social conditions we live in are in many important ways vastly different from those this behavior would have evolved in, forget the concept of "naturalistic fallacy", and take the above as vindication of traditional gender roles. :/

Pierce R. Butler:

You might also want to try Desmond Morris' books, namely Naked Ape, Human Zoo and Intimate Behaviour. These are quite old (NA was published in 1967) but they are still in print and offer some interesting viewpoints. They actually had a fairly significant impact to the development my worldview: Morris (zoologist and ethologist) discusses humans as just another species of animal and I was pretty young (about 12-13yrs IIRC) when I read them the first time.

The theory is that lack of estrus and concealed ovulation, and the ability of humans to copulate "for fun" are meant to strengthen the pair-bond between the couple: hidden ovulation means that the male doesn't know when the female is fertile and in effect needs to pay attention to her for the whole duration of the cycle to be certain of his paternity, and the ability to have mutual enjoyment leads to greater sense of companionship and increases the likelyhood that the couple stays together. This is necessary because human children need care for a significantly longer time than do any other animal young. (To compress a long discussion into 2 sentences..)

The books were controversial at the time when they were published, and still are, but they are quite intresting and well worth reading, IMO.

PZ, I think you might have a record here - 162 comments (and counting) and not one about the original article you pointed people to!

Let me buck the trend here by saying that the article sucked. I surprised it got past your editorial filter and that you recommended it to people, unless you were just pandering for blog traffic.

First, the subtitle should have been "LACK OF Insight..." since the article spends most of its length telling us how interesting the subject is, why mice are used, and describing the grossest level of intervention (castration), before admitting that there is only one study in humans with halfway meaningful results. No nuanced discussion of development, pathways, etc. that I've come to expect of articles you link to.

Second, what about this "maybe we shouldn't do science on controversial subjects" attitude? Didn't that trouble you?

This article was a complete waste of space. Both in the original journal, and here. You could have generated the same comment stream with a one line blog entry "Should gays suck face in public, discuss amongst yourselves."

By David vun Kannon (not verified) on 13 Aug 2007 #permalink

Frost - You & I may have read Naked Ape at around the same time, to similar effect.

Azkyroth & Frost: One key problem (in my mind, anyhow) with the idea that y'all outline is that, sfaik, this seems unique to humans. Other species which invest heavily in raising small numbers of young, or which pair-bond seasonally or for life, do not seem to have abandoned or greatly reduced estrus.

There are other apparently human-only reproductive anomalies which may be related to this question, such as permanently-enlarged female breasts, relatively extreme menstruation, and atrophied vomeronasal pheromone receptors. Another key factor is the difficulty and danger of human birth, given that infant brain size seems to have outgrown pelvic and birth-canal width, evidence that the former occurred very rapidly in evolutionary terms, and under severe selective pressure.

Paleontologists report that artifacts found with (proto-)human remains from the period of major cranial expansion are virtually identical: signs of technological change only after brain size has stabilized. Of course, that tells us nothing of our ancestors' wooden, fiber, etc tools which disintegrated over the millennia, but it does add to the puzzle of just how and why humans came to be as we are. Just what sort of advantage came with large brains that could override the extreme penalty of greatly increased maternal/infant mortality?

I suspect the same rule applies in this as in other great classical mysteries: cherchez la femme!

By Pierce R. Butler (not verified) on 13 Aug 2007 #permalink

it's additionally that each of the two "models" would actually define the other model as unattractive based on criteria in the first model.

I think that's where homophobia comes from.

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Regarding all the sociobiology on the concealed estrus, be sure not to make up speculations that require knowledge about the fact that intercourse and birth are somehow causally connected. This is not something that people normally notice on their own. I don't know if there are any left, but there were plenty of hunter-gatherer cultures way into the 20th century who had no idea.

By David Marjanović (not verified) on 13 Aug 2007 #permalink

aaron posted:

But if our ancestors were further inclined toward (and capable of) maximizing non-reproductive sex, then there would be evolutionary pressure to make the job harder for them.

Windy said:

The "women were afraid of childbirth and started avoiding sex during ovulation" argument? Nonsense, if you ask me.

Actually, I got exactly the opposite sense. It's not that women were afraid of childbirth, it's that the MEN were. Having estrus disappear and ovulation hidden is an advantage for the women of a breeding population where males have figured out the consequences of sex but still wish to be multi-partnered.

Provided that at the time, babies take as much, or nearly so, energy to care for as they do now, if males have figured out that having sex with a female in heat means that there's a great possibility of having offspring, then you can very well have a separation of female populations. The first, and smaller population, is the females that males actually want to have babies with, the second is the population that males want to have fun sex with. Hiding your ovulation is a wonderful strategy if you're in the second population, and not a bad strategy if you're in the first.

Does this mean that things happened this way? No, I'm no evolutionary biologist so this is less than speculation, but I also don't think that it's quite doing justice to human intelligence by pointing out that SOME populations of humans didn't figure out the connection between sex and babies and then stating that therefore ALL populations of humans prior to some time period hadn't done so either.

I just found it interesting that given the same statement, we could come to such opposite judgments.

it's additionally that each of the two "models" would actually define the other model as unattractive based on criteria in the first model.

I think that's where homophobia comes from.

-------------------

Regarding all the sociobiology on the concealed estrus, be sure not to make up speculations that require knowledge about the fact that intercourse and birth are somehow causally connected. This is not something that people normally notice on their own. I don't know if there are any left, but there were plenty of hunter-gatherer cultures way into the 20th century who had no idea.

By David Marjanović (not verified) on 13 Aug 2007 #permalink