Bring Your Questions for Mara Hvistendahl, Author of Unnatural Selection

Mara Hvistendahl‘s research features prominently in our latest podcast, “Misadventures in Baby-Making.” Her book, Unnatural Selection: Choosing Boys Over Girls and the Consequences of a World Full of Men, looks at how advancements in prenatal technology have led to extreme cases of gender selection across much of Asia.

As economic development spurs people in developing countries to have fewer children and gives them access to technologies such as ultrasound, parents are making sure that at least one of their children is a boy. As a result, sex-selective abortion has left more than 160 million females “missing” from Asia’s population. It’s estimated that by 2020, 15 percent of men in China and northwest India will have no female counterpart. The consequences of that imbalance are far-reaching and include rises in sex-trafficking, bride-buying and a spike in crime as well.

Mara is currently a Beijing-based correspondent for Science. She has kindly agreed to answer your questions on her book and research. So, as always, fire away in the comments section, and we will post her replies in due course. In the meantime, here is the table of contents of Unnatural Selection.

Part One: “Everyone Has Boys Now”
Chapter One: The Demographer
Chapter Two: The Parent
Chapter Three: The Economist
Chapter Four: The Doctor
Chapter Five: The Imperialist

Part Two: A Great Idea
Chapter Six: The Student
Chapter Seven: The Doomsayer
Chapter Eight: The Geneticist
Chapter Nine: The General
Chapter Ten: The Feminist

Part Three: The Womanless World
Chapter Eleven: The Bride
Chapter Twelve: The Prostitute
Chapter Thirteen: The Bachelor
Chapter Fourteen: The World
Chapter Fifteen: The Baby

This post is no longer accepting comments. The answers to the Q&A can be found here.


Trying to think freakonomically, and not having read Unnatural Selection yet, I would think that any argument about the consequences of males not having a "counterpart" in terms of numbers should need to account for how that plays out in countries (like in Saudi Arabia) where men are allowed more than one wife, and thus causing a shortage of women for other men without doing it by birth rate. Are the effects claimed for the shortage-by-prebirth-technology seen in these countries too?


Given the one-child policy in China, wouldn't sex-selective abortion be simultaneously generating 'extra' boys in place of 'missing' girls? Do estimates of total missing females account for such an effect, or is the male birth rate treated as independent of parental preferences?

Mike B

While there certainly are downsides with unattached men getting into trouble and being rowdy, won't a shortage in females help increase the value and position of women in cultures that have been historically resistant to providing them an equal place in society? In theory they should be able to demand higher standards during courtship and once married the threat of divorce would ensure better behavior on the part of men. Of course a shortage of workers is one of the economic per-requisites to slavery so I guess it can go both ways.

Other advantages include future population declines due to the lack of females and enhanced tolerance for homosexual men to help reduce demand.


I'm curious about potentially positive unexpected outcomes of the one child policy in China in terms of gender equality and opportunity for women. I would expect that for many families, resources that otherwise might have been disproportionally channeled towards sons had there been multiple children, are instead focused on a single daughter. Wouldn't this have substantial impacts in terms of education, expectations, status, employment opportunity, earning power, etc. for women born since 1980?


I've read Unnatural Selection, and it left me curious about the demographics of aging countries.

You stated that in some areas that had periods with very high sex ratio imbalances, they tended to reduce over time. Is there enough data yet to indicate whether overall birth rate recovers in the following generation, or does it become a downward spiral of shrinking population? Presumably the number of children per woman will have to go up, or the population will shrink in each subsequent generation.

It seems like the whole world is struggling to find a way to succeed with shrinking populations and shrinking consumer markets. Do missing girls accelerate the shrinkage?


Struggling to succeed with shrinking population? Are you kidding me? The last thing China, India, and the world at large need are MORE children. We're bumping up against 7 billion and can barely (if at all) feed what we have. Sounds like a blessing in disguise.


as to the sex-trafficking issue: is the overall increase in trafficking towards areas of wealth (first world) or towards areas of unnatural selection (Asia)


I can't help but wonder why it is that, in all the discussions I've seen on this problem, no one seems to think outside the conventional box to the obvious solution: plural marriage. See for instance R.A. Heinlein's "The Moon is a Harsh Mistress", in which the same problem is addressed.

Michael Lewin

What kind of incentive or deterrent - legal, economical or other - do you think could stop this practice without penalizing those who have an abortion for other reasons?


Seems like Asia may need to embrace polyandry - whereby a woman would have multiple husbands, but they would all be married only to her.

The only instance of this that I can recall is in a tiny Himalayan culture and is actually fraternal polyandry ( a woman married to all the brothers of another family). It's basically to prevent land division among the brothers.

Needless to say the women come out badly in this arrangement too, as they now have to do all the housework for all of their husbands.


...the more natural consequence would be the lousiest 15% of males don't get to reproduce. Not necessarily a bad thing?


It would be nice to think so, but seriously, how many women do you know who are (or have been) married to total jerks?


We often hear news reports from India about horrific family feuds having to do with the size (and contents of ) the dowry given by the bride's family to the groom's family. With the new reality in some areas where women will be in high demand, do you envision a cultural change where the bride's family won't have to provide as much in a dowry (or perhaps not provide one at all)? Or maybe even a reversal where the groom's family pays a dowry?


Do you think there is a "steady state" male/female percentage preference and if so what do you think it is? That is, will the ratio get skewed to the point where preference for females gains ground? So, a father who would otherwise strongly prefer a boy might look at the world and say, well I think I want a girl now - life will be pretty good for her; a lot of potential mates to choose from.

caleb b

I went to a small college where men outnumbered women 2:1 and one readily available observation is this...ugly women benefit in this scenario.

So I would expect that in Chapter 12 that the prostitutes would be uglier, but command a higher price.

Mike B

A friend who went to a popular engineering school with a 2 to 1 male ratio noticed that. The running joke was that upon receiving their degrees the University President would shake their hands and say "congratulations, you're ugly again".

Eric M. Jones.

I see this as an issue where it has been decided a priori that it won't be acceptable to have many more men than women...because of what??? You might notice that it hasn't been going so swell lately anyway. The notion that we should have one-man for one-woman seems quaint, but I don't see that this has occurred except in storybooks.

The truth is that there is considerable partner changing, and marriages didn't last longer in the 1800's than they do now.

Only PEOPLE last longer.


Ms. Hvistendahl,

Have there ever been examples in history of skewed gender ratios among populations? If so, what caused the skewed gender ratios of the past? The only thing I can think of would be infanticide? If this has happened in the past, what happened to those societies? The increase in crime seems like a pretty serious problem. Did that repeat in the past? If so, did the increased personal aggression also manifested itself in increased societal aggression, a.k.a. war?

Thank you for thinking about and (hopefully) answering my questions.


Basil White

Right now the market favors boys. When there's a shortage the market will favor girls. I don't find gender selection all that unnatural, or a new phenomenon. How do we know that baby girls haven't been disappearing for millenia?