Study Explains Why Women Miscarry More Males During Tough Times

sciencehabit writes In times of trouble, multiple studies have shown, more girls are born than boys. No one knows why, but men need not worry about being overrun by women. An analysis of old church records in Finland has revealed that the boys that are born in stressful times survive better than those born during less challenging periods. The work helps explain why women may have evolved a tendency to abort certain males and could lead to a better understanding of miscarriages.

Comments

It's the production line

[Todd Knarr]

Times of stress/trouble usually mean a loss of population. The arithmetic's simple: one woman can bear one child every 9 months to a year, while one man can sire multiple children in that same time. That means that adding female offspring at the expense of male will make it easier to recover the population loss. And of course sacrificing the least resilient male offspring favors the ones that'll survive the longest and sire the most children. The fun question is how the mechanisms that've evolved to make this happen actually work. Figuring that out's going to keep researchers occupied for the next century or two.

Re:It's the production line

[jimmydevice]

Ungulates can re-absorb a fetus during times of stress and insufficient feed.

Re:You are not in control

[ShanghaiBill]

Deer will also disproportionately abort male fetuses during harsh winters. Offspring born after hard times are likely to be stunted and inferior. Even if they are disadvantaged, a female offspring is still likely to reproduce. But with males, reproduction is more "winner take all". This is certainly true with deer, where a superior buck will mate with many does. But it is also true with humans, were men are more likely to have either many children or none. So carrying a disadvantaged son to term, when he is likely to be unable to find a mate, is a waste of resources.

I am going to take this a step further

[Taco Cowboy]

Be forewarned, this message ain't gonna be Politically Correct

Babies born under hard times don't grown up to be homosexuals

If we are to survey the demography of various countries there is a clear pattern ... that countries with larger percentage of homosexuals, bisexuals, trans-sexuals, and all that (male or female) tend to be those that are relatively more peaceful, with more plentiful offerings of food, and all that

Not to say that there is an absolute zero percentage of baby born during hard times that grow up to be homosexual ... there are always the exception

Take China, for examples ... during the warring / turbulent years (since the late 1800's to the late 1960's) percentage of Chinese homosexuals were very low

Now? With relative wealth and comfort, new generations that were born into kinder and gentler surroundings are experiencing an increase of the homosexual population

Re:I am going to take this a step further

[Swampash]

Shortsightedness is certainly an aid to finding a mate :)

Seriously though, the presence of male homosexuals in a tribe gives that tribe an advantage over all its hetero-only neighbors. They're males who aren't competition for breeding partners. Competition for breeding partners is the #1 source of self-destructive crazy in any tribal group, hell just look at Islam.

Selfish gene: highly misunderstood term

[140Mandak262Jamuna]

Richard Dawkins' book the Selfish Gene is probably one of the most misunderstood book titles ever. Dawkins was too clever for his own good, and you need to read his entire book to get to what he means by that term. He most definitely does not mean "there is a gene that makes people/organisms selfish".

He goes after the chicken and egg problem. Most people think of the egg as chicken's way of making a new chicken. But it is equally plausible, the chicken is merely the egg's way of making a new egg. We think we use genes to more copies of ourselves. Can we consider the genes are making more copies of themselves using us, the humans as a species, as mere replicating machine or incubator?

The question he poses is, "Are genes our selfish way of making more copies of ourselves? Or we are merely replicating machines under the control of the selfish genes?". He takes half the book to make people understand the question. Then the other half to prove, indeed the genes are in control and we are mere replicators. Some of the genes we have in our bodies have copies living in other species, other genera. Some of them are 100 million years old. The genes as a whole are the selfish ones vis a vis the organisms as a whole. They survive. We don't. We as individuals, we as species, we as genus are dispensable. The genes, as a whole, are selfish compared to the animal bodies they live in. The Selfish Gene. Not gene for selfishness.