Sex ratio at birth and racial differences: why do black women give birth to more females than non-black women?

The two important questions that this paper will attempt to answer are: (1) why is it that regardless of race/ethnicity or geographic location, the sex ratio data at birth show more males than females?; and (2) Why is it that regardless of geographic location compared to other racial/ethnic groups, Black women or Women of sub-Saharan Black African descent tend to give birth to more females? Or to put this question the other way around, compared to Black women, why do non-Black women give birth to more males?