Usually, an article related to the process of sex selection would sadden me because I think the brown preference for boys blows, but this one which was submitted to our news tab (Thanks, Premii!) had me laughing, because I immediately thought of celebrity evidence to back it up. Apparently, it is possible to choose whether you are going to have a male or female…calf:
Want to have a baby boy? Tuck into the burgers, fries and ice cream. Want a girl? Then go on a diet and lose some weight.
It works for cows, according to John Roche, a scientist at New Zealand’s dairy research organisation Dexcel. “And we would expect what holds true for one mammal will hold true across the board,” he said.
Also, if it can be applied to celebrities, it must be true. Angelina stayed rather sleek while incubating the most attractive celebrity baby possible, to the point where useless weeklies which cost $1.99 and all run the same story (though with slightly different covers) speculated that based on the lack of fat around her elbows, the lippy star was way too skinny. (I kid you not. I read this while waiting for my train.) Angelina, the magazines screeched, was “dangerously thin”. She had a girl, in case you haven’t had access to television, radio, newspapers, the internet, carrier pigeons, flaming arrows etc.
Meanwhile, Kate Hudson put on an amount which was almost equivalent to my mother’s entire body weight pre-pregnancy-with me; Hudson gave birth to a boy, Ryder. Britney…well, we all know about Britney. Do not read anything in to the fact that the quote I’m about to use contains the word “heifers”. I am establishing no connection between Britney and one of those. If you are currently thinking that thought, it’s your bad, not mine. 😉
They found that cows that gained weight before conceiving were more likely to give birth to bull calves. Those shedding kilos before conception had a better chance of producing heifers (females).
Roche told the Waikato Times , published in Hamilton at the heart of New Zealand dairying country, the research underlined the theory that humans had some control over the sex of their children…Roche said it was not clear exactly why weight affected the sex of a cow’s offspring.
I hope none of those troglodyte Uncles (or their Mothers) who blame their poor wives (or daughters-in-law) for failure to bear an heir with outdoor plumbing reads the following, lest they somehow feel vindicated…ugh.
Although the male determined the sex of the embryo at conception, the female had some control over whether to keep a male or a female one.
…Roche said a cow losing weight before conception may have some mechanism that prompted it to reject a male embryo because it was not up to supporting the development of a bull calf.
I know that the above quote is referring to pregnancy, but whatever. (Razib, don’t hurt me!) Like it’s so difficult to take care of little boys. They eat, sleep and poo (…much like their adult counterparts). If they are taxing at all, it might be in their inexplicable taste in music; the perfect, adorable, scrumptious baby you see pictured above is “drumming” along to some Rush concert movie. I like Rush about as much as I like crustaceans.
Finally, now you know that you would buy me pink or lilac baby shower gifts; if I ever do decide to procreate, then like my Mother who is vegetarian, I’ll apparently have girls. Good for me. 🙂
trivers-willard hypothesis.
also, there are other weird things you can do with farm animals to skew sex ratio. some of this is not in wide circulation because the animal industry doesn’t like to divulge ‘industry secrets.’ one example that i heard was that changing the sugar balance of male llama semen can flip the chances of insemination by X or Y sperm a lot.
at least the baby was dressed.
also, this phenomenon (trivers-willard) seems to be documented in red deer, a related group of bovids. so no surprise that cows do this.
also, cute baby.
Thanks! He’s my Godson, but I’ll take total and undeserved credit for his gorgeousness. 😉 Omg, I TOTALLY fattened up his Mother while she was pregnant with him via standing dates at Macaroni Grill, chocolate, samosa chaat etc. The theory works???
Omg, I TOTALLY fattened up his Mother while she was pregnant with him via standing dates at Macaroni Grill, chocolate, samosa chaat etc. The theory works???
not to be morbid, but you might have reduced his chance of being spontaneously aborted. it seems that anymore from 25-75% of implanted embroyos are spontaneously aborted, most of the time no one knows (this is why the numbers can be hard to come by).
I read a LONG time ago that supposedly the father’s fitness levels could determine sex as well — the healthier and more athletic the dad was, the more likely he was to have a daughter. The fat slobs tend to have sons, supposedly. Correlation at all? (neither theory explains skeletal Posh and footballer Becks’ 3 sons, though) 😉
razib — i thought i remember learning in embryology (waaay back in the day) that the spontaneous abortion was the body’s way of rejecting a poorly developing embryo? given all that can go wrong at a genetic level during the formation of a zygote, that seems to make sense.
razib — i thought i remember learning in embryology (waaay back in the day) that the spontaneous abortion was the body’s way of rejecting a poorly developing embryo? given all that can go wrong at a genetic level during the formation of a zygote, that seems to make sense.
yeah, though the body doesn’t always initiate, a lot of the embryo dies, so it just gets expelled. humans are prone to many karytope level mutations…down syndrome and the other trisomies are the tiny % that aren’t lethal. of course that doesn’t say anything about point mutations, etc., but these are probably not as determistically lethal as aneuploidies. in regards to this issue, sex ratio, it is likely that many lethal sex-linked loss of function mutations result in the spontaneous abortion of a greater number of male fetuses.
as for the father’s fitness, i haven’t heard of that, though there is evidence that “older” sperm (sperm from older men) seems to result in an increase in pathologies in their children (male reproductive function slowly breaks down, so the % of functional sperm decreases and no doubt the proportion that is mutationally damaged is greater).
why undeserved? i always claim bragging rights for all my little nephews, nieces and even for the kids next door. the kid can’t brag, someone has to do it for him. so the way i see it, you are doing him a favor. 🙂
Hmmm… Princeton bib? Yeah, that’s a desi baby alright 😉
‘Do not read anything in to the fact that the quote IÂ’m about to use contains the word “heifers”. I am establishing no connection between Britney and one of those. If you are currently thinking that thought, itÂ’s your bad, not mine. ;)’
Hilarious! I can assure you that there are plenty of others who already have established such a connection and continue to do so. After all, Britney’s transformation from, uh… well, let’s not go there, I think we can all use our imagination here. 🙂
BTW, this is totally off-topic but just as a little public service announcement from one Desi to his legions of compatriots in the great halls of Sepia Mutiny:
For your own good, if you have any professional aspirations to work in the US, please budget into your schedule some plans to take courses in conversational and professional Spanish– and get fluent. I’m in the accounting/auditing field, and it’s now gotten to the point that quite a few firms in California/Arizona, as well as in some big cities like New York/Chicago as well as in Florida, won’t hire you without strong Spanish language skills. The same is starting to apply for e.g. law firms, nursing jobs and even retail. If you don’t have Spanish skills, an awful lot of employers these days will take one look at your job application– and toss it into the rubbish pail. Even those who do hire you, will pay you $25,000 a year less than others who can handle Spanish. If you’re still in the Subcontinent, it’s getting to the point that for many fields, I’d suggest you delay applying for a visa until you’ve at least gotten some basic Spanish conversational skills. Eventually, you’ll need to not only be fluent, but also be able to handle official Spanish for formal documents like contracts as well as business negotiations over the phone.
I found this out the hard way myself, as have several of my friends when we’re already struggling to pay off our debts and get a foothold– Spanish fluency translates into jobs and a big boost to your salary for all kinds of jobs, and you just have to have it. You’re tying a straitjacket around your career without it. Moreover, this isn’t just a temporary thing. I was speaking to an old classmate of mine who’s now a lawyer, and apparently, Spanish has official protection and recognition throughout the entire Southwestern USA– including California and Texas– due to the treaty arrangements that concluded the Mexican War that the US fought against Mexico in something like the 1850’s that led to the big transfer of territory from Mexico to USA. (Apparently something similar governs Florida– sorry, I was a B- student in history myself so I only know what my far more knowledgeable friend is able to relate!) So Spanish is here to stay and has a sort of official status throughout a big chunk of the country, and you just have to know it. Take courses, watch Spanish soap operas on the Spanish channels, practice at the deli, whatever you have to do to improve your conversational ability.
I can’t begin to describe how frustrating the job search has been for me here until recently. It’s only after I did some night school courses in conversational Spanish and used some tapes, that things have been perking up. I guess French and German are useful if you want to move to the EU (or to Canada, with French), but for the USA it’s Spanish. So if you alreasy speak, say Marathi, Hindi, English and Telugu, add Spanish to the list if you’re even thinking about North America. It’s pretty much an essential career move.
Hmmm, there might be something to the grandmother’s technique of sex determination in India, based on the size and shape of the ‘bulge’.
Subhash, sorry to hear about your troubles. How’s Chinese (Mandarin) for career prospects? Conversational spanish is not that difficult, I highly recommend a couple of months backpacking in any Latin American country 🙂
it seems that anymore from 25-75% of implanted embroyos are spontaneously aborted, most of the time no one knows (this is why the numbers can be hard to come by).
I was under the impression that male babies are more likely to be in trouble from conception to adulthood, so perhaps it’s not so much that a starving mother is more likely to have a girl as a baby girl is more likely to survive a starving mother. I mean, obviously the gender is determined at conception. So, say, girl-zygotes are more likely to get implanted in a starving mother. It’s also possible that starving does something to the conditions in the tubes and canal, so that even with an equal shot of x and y sperm, the x sperm make it upto the egg faster. And then, as above, a starving father might provide more x sperm to begin with.
Which makes me wonder. I’ve been told that during the Bengali Rennaissance there had been an excess birth of girls—which combined with the dowry system to lead to the social problems that inspired Vidyasagar to campaign for widow remarriage and female education. I have no way of verifying that kind of demographic data, but if true, it would also connect with the frequent famines in Bengal in the 18th and 19th century, and the general increase in poverty due to the tax collection. I wonder how that connects with the stories we read about here all the time. Starving farmers want sons because of cultural and economic prejudice, but their very starving increases the likelihood they have daughter. Yikes. Seems like yet another vicious loop in the vicious cycle.
I was under the impression that male babies are more likely to be in trouble from conception to adulthood, so perhaps it’s not so much that a starving mother is more likely to have a girl as a baby girl is more likely to survive a starving mother.
bingo. i elucidate the logic here.
Starving farmers want sons because of cultural and economic prejudice, but their very starving increases the likelihood they have daughter
one thing to note, low SES groups in many societies often aver son preference as a form of verbal elite emulation, but on the ground the issues are not so clear. south asia, like most regions (all that i know of), has some hypergamy, where females “marry up.” so, low SES families often have a much better shot of moving up the social ladder through marriage alliances via a daughter than a son. among the masai this has been documented among their “vassal” people. this group avers son-preference, but the reality is that sons have much higher rates of mortality than daughters. a survey of medieval european cemetaries showed many more daughters in aristocratic burial grounds than among the peasantry, where you had a reversed scenario. in other words, cultural biases and economics work at cross-purposes here….
Vat a cute kid, Anna! Keep him away from the Macaroni Grill and all – diabetes and social rejection down the road ain’t good at all. ;-))
Per the comment “Starving farmers want sons because of cultural and economic prejudice, but their very starving increases the likelihood they have daughter”
This study aside, i recall taking a class in population demographics from an expert in the field during my ivy league years. I always thought, like the conventional wisdom, that the poor people have more children for the sake of having more children to work on the farm, cultural mores, etc. But the data did not bear that out – it came down to emotional factors more than any economic reason. In other words, the bigger your family, the more love there is to go around. When you have little else, such extended affection and support system cannot be underestimated.
“it came down to emotional factors more than any economic reason. In other words, the bigger your family, the more love there is to go around. When you have little else, such extended affection and support system cannot be underestimated.”
There’s also “the bedroom is the poor man’s opera” reason. Four years of college and that’s one of the few things that stuck, go me! But I’m not completely convinced of the emotional factors being that important. It could also turn out to be that the larger the family, the less time they have to spend around each other because the parents are always working to support the kids. But I might just be too influenced by all those doordarshan ads showing how obscenely happy the families with two kids are 🙂
aare Sleepy, “the bedroom is the poor man’s opera” – i liked your comment. Too funny!
Cynical my man/woman, deliciously cynical….
Not injecting my personal opinion here, just what the data bore out (I just looked up my old notes to make sure I was not imagining those old teachings). Big difference between American families with several kids and those in impoverished places like India. Those ads promoting 2 child families sound like China, plus one child.
What a fascinating discussion, esp Saheli and Razib’s comments. I had heard of this too, that although the standard sex ratio worldwide generally does hover around 105:100 (boys:girls) on average, that at times of impoverishment, more girl babies may be born. I don’t know if it’s an X-sperm advantage, as much as that more boy babies are miscarried. IOW, nature ensures that substantially more boy babies are conceived, since fewer of them survive the various onslaughts (X-linked genetic disorders that cause in utero miscarriage, a variety of other problems) that stand in the way of a successful trip from conception to birth. A slight excess of boy babies are also born to help correct for losses in e.g. wars and accidents that occur before childbearing age sets in.
I’ve also heard that after wars, more boy than girl babies are born (i.e., above the 106:100 average) for reasons that aren’t clear, but that some people may suspect are due to the higher average-age of fathers in a postwar society, since younger men are killed in higher numbers– maybe older fathers have a higher Y:X sperm ratio, or something along those lines. In e.g. WWI the British were slaughtered en masse at Ypres and Somme, with many other young British men wounded so badly they couldn’t conceive. So in the 1920’s, the British M:F sex ratio went up as older men began to sire children, though that’s only one theory as to why it increased. (Some other demographer postulated there was also a “bump” in boy baby births after the British were wiped out by the Ghilzais in the Anglo-Afghan War in 1842, though since the Brits managed to get an awful lot of Desis killed in that war too, I’d bet that you may have seen a sudden uptick in boy baby births in affected villages in India, if this process still holds.)
It’s interesting that nature does seem to find ways to keep the M:F balance roughly the same in the midst of various environmental shocks or societal conflicts like wars. I wonder if these various checks and balances still apply in modern industrial society though, since there are factors impacting fertility in general for which I’m not sure there would have been evolutionary pressure. For example, there’s a dioxin-like compound in some plastics that have been popular in industry (I’ll try to find the link), which is deadly to sperm and has been proven to cause dreadful reductions in fertility in areas where pollution is high– the frogs in streams in those areas are infertile and have weird and troublesome gonadal deformities, and there seem to be much higher rates of human male infertility as well. IIRC Europe finally got its act together in the 1990’s and banned the compounds, or at least imposed stringent rules on waste disposal with very harsh penalties for lawbreakers. Whereas, the US Congress still stupidly allows the compounds to be used and is ridiculously lackadaisical in enforcing clean-up and disposal rules. It’s bad enough that these compounds are spilled into groundwater in the US, but many US multinationals also dump this sort of crap in developing countries where they have factories– Malaysia, African countries and I suspect India as well. Worst of all, we may not be seeing the worst effects of these things for another 15-20 years. Maybe Union Carbide in Bhopal wasn’t so exceptional after all.
It’s interesting that nature does seem to find ways to keep the M:F balance
this is a case of group/frequency dependent selection. as one sex becomes scarce there is an incentive for females to bias their offspring toward that sex since scarcity increases its fitness.
The way I understood it is that male fetal development is a brittler process than that of females, the default sex. I prefer to think of it as ‘tricky and advanced’ rather than ‘frail’ 😉