What happens when sex selection leaves a nation with significantly more men than women? In their controversial new MIT Press book Bare Branches: The Security Implications of Asia's Surplus Male Population, Valerie Hudson and Andrea den Boer assert that historically high male-to-female ratios can trigger domestic and international violence. Since the mid-1980s, widespread sex selection has skewed the sex ratios of some Asian countries--particularly China and India--in favor of males on a scale that may be unprecedented in human history. The authors argue that this disproportionate number of low-status young adult males threatens domestic stability and international security.

Regarding Chip's larger point, one practical step for undercutting the sentiment that developed countries need to jump start their population growth rates is to stop using misleading headlines like, say for example, the depopulation bomb.  Just to pick one.  Ben Wattenberg's Birth Dearth is another. Newspapers love it but we are heading to 9 billion at best before leveling off.  

Geoff Dabelko

One example she used (and I am painting this in very general, broad strokes) concerned the declining population in Europe and the population explosion in North Africa.  European nations need more workers.  North Africans need more jobs.  Unfortunately, the exhange or flow of population is discouraged/prohibited by the very European nations that need workers.  And, the North African population that is unemployed with no prospects but a dismal economic future grows increasingly frustrated and restless at the disparity they see. (Terrorism anyone?)  

The point being, unintended consequences will and do emerge in systems that are not entirely closed or entirely open.  Half measures only muck up the 'natural' tendency toward equilibrium. In non-economic terms, the pent-up anger, frustration and resentment will find some form of expression.  What will those 40 million single guys do?  I am not sure I want to speculate.

Therefore, the concerns discussed above are minor compared to the damage humans are doing just by their sheer numbers.  To answer Mr. Giller's first question, the point at which human fertility rates have declined too much is so far off in the future that it's not even worth contemplating.  The problem is how to humanely lower human population to an ecologically balanced level, and that level is a small percentage of the current human population.

Environmentalists should not be trying to convince people that "a country with a declining population can still be competitive economically and provide a high level of social services (Scandinavian or French style)."  What we should be doing is helping people to realize that land, air, water, plants, and non-human animals are more important than economic concerns.  While providing a high level of social services is a worthy goal to which we should aspire, doing so should not take precedence over, or come at the expense of, the evnironment.

Finally, unfounded fears about the possible results of the unnatural male-female ratio created by China's one-child policy do not override ecological or environmental concerns.  None of the writers above have any idea what this ratio will cause.  The most anyone said is that this ratio "can" cause domestic or international violence, and the latter claim is rather dubious.  While it is clear that China's leadership cares nothing about ecology or the environment, all environmentalists should hope that China does not change its one-child policy, which has greatly slowed its population growth.  Except for environmentalists who live where the population is already declining, what we should all be doing is trying to get our own countries to implement the same policy.

Jeff Hoffman