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Engineers Have More Sons, Nurses More Daughters
Bifurcati writes "While it might be irrelevant for many /.ers, a recent study has shown that people in stereotypically male professions (engineering, IT, mathematics, etc) are more likely to have sons than daughters, while nurses, therapists and teachers tend to produce more girls. Based on independent survey data, engineering types produce 140 boys to every 100 girls, while nurses and the like produce 135 girls to 100 boys. The explanation is unclear, but it might have interesting long-term social implications. A more detailed summary of the journal article is available on Illuminating Science."
Repeat after me: "Correlation does not imply causality."
I think it's far more likely that it's not what job you're doing, it's what job you tend to want to do.
This really seems like an interesting ratio that popped outof some calculations, i.e., nice, but not really meaningful.
/. and other places - correlation is not necessarily causation.
I mean, how would somebodies profession really determine his/her childs' sex? I'm sure that mining other datasets would lead to similar 'interesting' ratios/facts.
As has been mentioned on
I'm an EE, I have a good friend who's an EE, and another good friend who's a software E.
Among us there are five kids, and every single one of them is a girl. (They each have two, I have one)
Obviously we weren't included in the survey.
And when I worked at Atari, the Engineers and game developers were convinced that CRTs kill male sperm because most of them had baby girls, in fact I believe it was over 90% girls.
I think someones just yanking our chain.
Raydude
Male sperm is more abundant but weaker than female sperm. So in an amenable environment, male sperm are more likely to implant and reproduce. In a hostile environment, the hardier female sperm are more likely to survive.
I'm therefore not at all surprised by the result that couples are more likely than chance to have "more of the same" sex children.
I also would not discount the testosterone theory out of hand.
The actual article (Journal of Theoretical Biology, 233, p589-599 "Engineers have more sons, nurses have more daughters: an evolutionary psychological extension of Baron-Cohen's extreme male brain theory of autism" by Satoshi Kanazawa and Griet Vandermassen and available through Elsevier's Science Direct) came out in December 2004 an is available online for those whose institutions subscribe, notes the following correlations:
This is based on survey data from US professions of around 1500 people. Only some of the professions are categorized as "systemizing" and "empathizing" so presumably the sample size is much smaller than that . The sample size isn't listed directly in the article but it appears to be about 20% of the 1500 with at least one parent so categorized profession, for around 300 people or so. Most professions are neutral in the "systematizing/empathizing" continuum, apparently.
Amoung those with "systemizing occupations" had regression coefficients of
From the classification of professions:
Systemizing occupations
Empathizing occupations
Presumably other professions are regarded as neutral in this spectrum.
It's psychosomatic. You need a lobotomy. I'll get a saw.
We arent monkeys (well not completely).
What do you mean by "Dominance" or "Submissive" in your passage? Socio-economics? Family Politics? parenting style?
Im not so sure all the shit that applies to apes in the wild applies to humans -- we have a much larger social context that doesnt always sync with purely animal instincts.
The study did not say why this phenomenon occurred, but The Sunday Times quoted a specialist in evolutionary psychology as saying it could be because the children of "systemiser" parents appeared to encounter more testosterone in the womb, making their gender more likely to be male.
yeah, the above quotation from TFA destroys any reasonable claim to validity this study purports...in other words, this study/article/post is bullshit
Just more silly science. If they wanted to make this claim legitamitly, they would need to show a relationship between testosterone levels in men and women and the sex of their children, THEN they would have to show a relationship between a person's occupation and testosterone levels, while also accounting for any other variables (such as diet) that might alter testosterone levels in a person.
We've got a long way to go before this bullshit becomes actual science.
Thank you Dave Raggett
I think more importantly, it should be noted that perhaps this is false.
"Who is the Journal of Quantum Physics going to believe?" --Stephen Hawking
Of course, the media has promptly taken things one step further and suggested that "Couples desperate to produce a son could boost their chances if one or both of them switches to a "masculine" profession such as engineering or accountancy". Perhaps this is true - but that might be reading more into the report than is good for it.
Short people, if they switch to being tall, can improve their chances of having tall children.
Engineers aren't in their profession by accidentally not becoming nurses or teachers. I would have to state with fair certainty that one who becomes a nurse is probably - on the average, or even in the majority of cases - not of an engineering mind, personality, etc. And the reverse. The profession, statistically, would likely be an indicator of personality type in these rather extreme cases of the nurse versus the engineer. I know several nurses and teachers and a lot of engineers. They are rather opposites. The idea of the nurses or music teachers I know "switching" to engineering is flat-out absurd. While I won't rule out the possibility of the contribution of the professional environment to the children's sex determination, how deep the correlation goes is unknown. But it seems to me that statistically, the profession is only evidence of something far, far deeper.
must... stay... awake...
I agree! Especially since the male ALWAYS determines the sex of the child.
This is simply not true except in the most simplistic sense. Sperm counts (according to the wikipedia) have a normal range of 20 to 180 million per millileter. There are countless sperm carrying both the X and Y chromosone vying for the prize.
There are subtle differences between X and Y bearing sperm in robustness and mobility, IIRC; it is possible that the male can influence conception sex by producing sperm of each type that are relatively more or less fit with respect to each other, and that the female may likewise influence this by providing an environment that is relatively more or less challenging.
On the other hand, there is a huge difference between a male and female embryo. Males have a higher mortality rate throughout their lifetime. For example sex ratio at birth is slightly skewed male (typically something like a 5% difference), but the ratio gets more even as you approach adulthood through higher infant mortality rate.
There seems to be some evidence (gleaned from reading Science News and other sources), that this process of winnowing males starts in utero, although the situation is very complex sice we're talking environmental factors. For example, smoking parents tend to produce relatively more girls. This can be explained several ways: the male may damage his sperm; the female may make her uterus a more challenging enviornment for the fetus. Both parents are likely to be exposed to each others' second hand smoke.
I't hard to say for somebody outside the field following this through the popular science press, but the impression I get is that there have been a variety of studies which suggest that environmental stressors reduce the sex ratio at birth (reduce the number of males). Perhaps engineers have less stressful jobs than therapists?
Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
Maybe you generate more girls if you spend a big chunk of your day standing and walking around.
Intellectual property doubly so.
One family that I know swears by this method. They are four for four in getting it to work.
And this is EXACTLY why well-formulated scientifically rigorous studies are important. You want us to draw conclusions from "my one friend claims this workes for him". Gawd save us.
I can predict whether a flipped coin will be heads or tails based on whether the year it was minted is odd or even! I tried it 4 times, and it worked every time. Maybe differences in the amount of drag induced on thie flipping coin from the surface of the date stamp would help to explain this data.
Yes, maybe. Or maybe the theory is crap, and the "proof" is just random chance.
Just because we can recognize our own nature doesn't mean we are unaffected by it... realization of animal nature in ourselves only serves to recognize and alter it at the moment.
Our "animal" natures just have nice neat social labels... which makes them seem more "human"
The *only* thing that separates us from the animals is our self recognition... and even then, arguably, only marginally.
There are proponents of different techniques that supposedly let you choose the sex of your child. One interesting technique is called the Shettles Method. One family that I know swears by this method. They are four for four in getting it to work.
Either that or they're the the one out of sixteen who randomly get four children of sexes desired.
I'm thninking this guy should read the story about people who can't understand sarcasm posted today as well.
Hi honey, guess where you're sleeping tonight...
Only problem is were talking about humans here, who have quaint little institutions like marriage, bigammy and child maintainance laws and the like.
One - these institutions have been formalized for a couple of thousand years and even then not consistently, and even then only in a geographically limited areas or the globe. It's reasonable to hypothesize that this will not have yet over-ridden a million years of accumumlated genetic tendancies, and the correlation bears this out.
Two - are these institutions set in stone in modern society? Dominant males are more attractive to most girls and will still have a better chance of reproduction and are still more likely to have multiple partners.
Rather than merely hedging on the genetic or environmental factors, you should also have written "will either be passed on or not." Now that would be difficult to disagree with.
No I should not have written that as it was not what I meant. What I wrote was what I wanted to write and was correct. I'm not hypothesizing that might happen, I'm explaining why it does. the child of a dominant male is more likely to be male, with other factors controlled.
The biggest problem I have though is trying to understand what you actually mean by dominance-submission. Are you merely saying that there exist, within the male population, men who in a particular context at a particular time in leaders and followers? Are you inferring that the position they find themselves in at any particular juncture has been genetically determined? Are you saying that my promotion from copy boy to CEO of our company has had a Lamarckian effect upon my genetic material which I will now be able to pass onto my (male?) offspring? Or is it just that some guys aren't as good at sports?
The simple answer to all of them, is exactly what I said in my initial post, but I can elaborate for you. Taking you as an example - if you are a dominant male then your children are more likely to be male. Now whether this happens because you are dominant socially and your body understands this, or whether you are dominant because you are already genetically predisposed to dominance, I do not know. To the best of my knowledge the mechanism has yet to be explained, but I could well be out of date. I'm willing to stake someone's money that the process is not 'Lamarckian' however.
Still, I would make an educated guess that it is not genetic, but rather environmental that determines this effect. My reason is both theoretical - it is not advantageous to the species that dominance should be inflexibly aligned with other traits, but should vary according to what traits are currently beneficial - and anecdotal. I have found that dominance-submission can be determined early in childhood through experiences rather than pre-determined. Anyway, this last paragraph is personal conjecture and will remain as such. The previous paragraphs are the answer to your questions.
Aide-toi, le Ciel t'aidera - Jeanne D'Arc.