送交者: mangolasi 于 2005-8-25, 08:21:11:
回答: 昨天刚在英国图书过看的英国人口统计(2001): 由 gordon 于 2005-8-25, 07:40:43:
the point of being conceived: male-female ratio are higher when being conceived, a little bit lower at the point of birth (male fetus are more easily miscarried), and lower and lower at the later stages of life--if they are treated equally in terms of food and health care.
There had been some research on the decreasing male-female ratio (i.e. more female babies that the "natural" rate) in the industrial countries. One attribute it to the raising single mother ratio: If the mother get irregular sex before conceiving, it might probably sending some singal that she doesn't has a regular partner to help her raise the baby. Hence she is more likely to conceive a girl than a boy because girl is more likely to survive and reproduce in an unfavorable environment.
However, the 119:100 is not only the artifact of sex selection before birth, but also evidence of neglecting female babies: if female babies are treated equally or even slightly inferiorly in terms of food and medical treatment, the male-female ratio would be lower. It would be very interesting to disentangle these 2 effects: selective abortion would raise some moral questions about abortion and totalitarian state policy, while the second effect raised more general moral question on the social norm which value male more.