Two economists suggest that China would be a more peaceful place if it had more women:
[Jane] Golley and [Rod] Tyers are building off existing research, which confirms that China’s crime rate has doubled over the last 20 years and that incidents of social unrest have risen from about 40,000 in 2001 to over 90,000 in 2009. China’s imbalanced sex ratio is likely a leading cause: A 2008 study by the Institute for the Study of Labor found that a 1 percent increase in the sex ratio leads to a 5 percent increase in the crime rate. And regions with the most male-biased sex ratios also have more gambling, alcohol and drug abuse, prostitution, rape, bride abduction, and human trafficking. Using demographic and economic projections, Golley and Tyers concluded that gender “re-balancing” could bring about a reduction in crime and a rise in productivity.
Perhaps aware that this all still has a simplistic ring, Golley and Tyers cite anthropological studies which show that in societies with surplus men, males have a greater tendency to engage in non-productive and risky “wife-seeking” behavior. And this theory isn’t new: In the 2004 book, Bare Branches: The Security Implications of Asia’s Surplus Male Population, Andrea den Boer and Valerie Hudson showed that high male sex ratios can also lead to more authoritarian forms of government as authorities try to crack down on crime.