Behavioral Ecology and Sociobiology, Vol. 52, No. 2 (Jul., 2002), pp. 109-116 (8 pages) I studied patterns of sex ratio variation in 543 fledglings from 192 broods of Montagu's harriers Circus ...

Sex ratio has been studied from many theoretical and empirical perspectives, but a general assumption in sex ratio research is that changes in sex ratio occur because of selection on sex ratio itself.

A new analysis of sibling records from more than 300,000 individuals suggests that some parents continue to reproduce until they have children of both sexes. A new analysis of sibling records from ...