Remarkably high sex ratios at birth have been observed recently in Asian populations. 高出生性別比常常發(fā)生在亞洲的人口中。
What happens to the sex ratio at birth if fertility is maintained at a low level depends on the evolution of son preference. 如果生育率維持在低水平上,出生性別比的前景取決于男孩偏好的演化。