As wilting said, they're missing as in not born. The natural sex ratio or any given population is between 104-106 males to females. In some countries, particularly in Asia, the ratio is skewed to an extent that is unnatural (I don't have the book to hand, but in some areas of China its around 173:100). A ratio that skewed shows that there's people intervening in sex selection, be it by aborting female fetuses, infanticide or some other means. Rajasthan, Albania, Georgia, areas of China and Azberbaijan (I think?) have really skewed sex ratios, and the argument of cultural/religious preference doesn't stand up really, as they're all quite different (though she doesn't really get to the bottom of why in all instances, just that boys are favoured). South Korea used to, but have managed to sort it out.
Thanks Dum. I look forward to it.
Cote - how are you managing with the piano, or making the time? I used to play, but stopped in my late teens. I now have a piano (it was my grandparent's, and I went to great trouble moving it into the flat so it can primarily serve as a place to put photo frames
). Are you taking classes? I need a kick up the butt to start playing properly again.