Why does war breed more boys?

[murraybiscuit]

It's a fairly well known phenomenon that after countries have fought a war, their population experiences higher male birthrates. Why is this? The author of this article theorises that gender selection is a heritable gene carried by males. That in normal society, there is a range of gender bias - from female bias, to neutral, to male bias. The phenomenon happens because there's a greater prevalence of males with male-producing makeup who go to war. Therefore, on average, proportionally less of these die than female-biased producers. I'm not entirely sure however, how society reaches equilibrium again, but it's an interesting idea.

http://www.popsci.com/scitech/article/2008-12/why-does-war-breed-more-boys

Thoughts?

 

[BTTB]

I browsed a few of the comments from the readers below the article which makes for mature and interesting reading.

The testosterone argument was food for thought, during war men would have higher levels of this hormone which could stimulate the production of more male sperm?

One notion I found interesting was a discussion I had with our Gynaecologist when our son was born in 1991. I posed a question to him in regards to the abnormal ratio of woman to men in the Cape, apparently 8 to 1. He claimed that stress caused the male to produce more female chromosome laden sperm.
The question then begs are Cape Town men more stressed that in other centres and in my opinion it doesn't seem so, in actual fact most Capetonians seems more laid back?

 

[zizo911]

Everyperdon has a 50% chance of having a male or female offspring. It is just mere co incidence.

 

[Willie Trombone]

It's a fairly well known phenomenon that after countries have fought a war, their population experiences higher male birthrates. Why is this? The author of this article theorises that gender selection is a heritable gene carried by males. That in normal society, there is a range of gender bias - from female bias, to neutral, to male bias. The phenomenon happens because there's a greater prevalence of males with male-producing makeup who go to war. Therefore, on average, proportionally less of these die than female-biased producers. I'm not entirely sure however, how society reaches equilibrium again, but it's an interesting idea.

http://www.popsci.com/scitech/article/2008-12/why-does-war-breed-more-boys

Thoughts?

I'm struggling to follow the bold bit.

*EDIT* I think I have it now... I guess we don't have huge families to prove it but it's possible some tend towards making males vs females though it's still a bit of a lottery - there's surely no way all your sperm are going to be one or the other. Is it possible to analyze a single sperm and determine this? Can one have tests done before conception to determine the likelihood of male vs female?

 

[Willie Trombone]

Everyperdon has a 50% chance of having a male or female offspring. It is just mere co incidence.

I doubt that personally. I think 'the system' is a little more sophisticated than you give it credit for. Even in animals - with Crocodiles, the incubation temperature determines the sex - 1 degree either side of the 'middle of the road' in a stable incubator and you're producing males or females vs mixed.

 

[Kornhub]

I doubt that personally. I think 'the system' is a little more sophisticated than you give it credit for. Even in animals - with Crocodiles, the incubation temperature determines the sex - 1 degree either side of the 'middle of the road' in a stable incubator and you're producing males or females vs mixed.

Agreed

 

[zizo911]

I doubt that personally. I think 'the system' is a little more sophisticated than you give it credit for. Even in animals - with Crocodiles, the incubation temperature determines the sex - 1 degree either side of the 'middle of the road' in a stable incubator and you're producing males or females vs mixed.

It is based on simple genetics, it is a males Y chromosome that determines the gender of the offspring. Doing a SIMPLE genetic cross it shows that you will always have a 50% chance of males.

 

[Willie Trombone]

It is based on simple genetics, it is a males Y chromosome that determines the gender of the offspring. Doing a SIMPLE genetic cross it shows that you will always have a 50% chance of males.

Um... and the same goes for a males X chromosome in producing females - thats the obvious bit.

And again my Q is (and I'm not expert)... is each sperm already sexed? If yes, why shouldn't there be the possibility of producing more of one than the other?

 

[zizo911]

Agreed

I'm not saying that I have a doctorate in genetics. But from what I've been thought, is that you have either chance of having a female or a male.

 

[Willie Trombone]

I'm not saying that I have a doctorate in genetics. But from what I've been thought, is that you have either chance of having a female or a male.

Sperm can be sexed...
http://en.wikipedia.org/wiki/Sperm_sorting

The argument above is that external factors may have a say in the likelyhood of male sperm being dominant in certain environments through many factors, including survival of men who produce more male sperm than female (for example). I think it's feasable.

Also, it's feasable IMO that one person may be predisposed to producing more of one sex than another purely by genetics (environmental factors aside).

And if you were willing to do the hard work, you may even find that such men are predisposed to copulation during war time
Ok, that was a dig but you get the point heh.

 

[zizo911]

Um... and the same goes for a males X chromosome in producing females - thats the obvious bit.

And again my Q is (and I'm not expert)... is each sperm already sexed? If yes, why shouldn't there be the possibility of producing more of one than the other?

Yes, each sperm cell is 'sexed'. During meisos these cells become haploid and 23 from the father and 23 from the mother are fused together to form a zygote. There might be a possibility of a male producing a certain number of 'male sperm'. But in general, the chances are 50%. I personally don't know of any way to make more 'male sprem'. Genetics is a very interesting and debatable topic, glad someone brought it up.

 

[zizo911]

Sperm can be sexed...
http://en.wikipedia.org/wiki/Sperm_sorting

The argument above is that external factors may have a say in the likelyhood of male sperm being dominant in certain environments through many factors, including survival of men who produce more male sperm than female (for example). I think it's feasable.

Also, it's feasable IMO that one person may be predisposed to producing more of one sex than another purely by genetics (environmental factors aside).

And if you were willing to do the hard work, you may even find that such men are predisposed to copulation during war time
Ok, that was a dig but you get the point heh.

Yes I get it, but Wikipedia is not always a reliable source, just saying.

 

[HeftyCrab]

Hmmmm.i was told that if you want a boy you must have sex closer to the womans ovulation as the 'male' sperm cells swim faster than the females. if you want a girl you must have sex a while longer before the womans ovulation because even though the 'female' sperm swim slower,they live longer.so by the time the ovulation occurs most of the male sperm has died.

 

[Willie Trombone]

Yes I get it, but Wikipedia is not always a reliable source, just saying.

+1 on that, just being lazy

 

[Willie Trombone]

It's a fairly well known phenomenon that after countries have fought a war, their population experiences higher male birthrates.

BECAUSE THEY EAT MORE BANANAS!
http://edition.cnn.com/2008/HEALTH/04/23/gender.diet/index.html

Or is it they have fatty breakfasts?
http://www.telegraph.co.uk/health/h...gnancy-increases-chances-of-having-a-boy.html

Or is it just chance?
http://www.telegraph.co.uk/technology/3334667/All-boys-Its-only-chance.html

 

[IdlePhaedrus]

It's a fairly well known phenomenon that after countries have fought a war, their population experiences higher male birthrates.
Thoughts?

Interesting, I was always under the impression that it worked the other way around, when there are a lot of male children born, war was often the result.

 

[Willie Trombone]

One doesn't deny the other.