“…Zhang (2011) found that in the majority of 43 countries across the globe, levels of male fertility were lower than levels of female fertility; but also that when levels of fertility were high, male fertility tended to be relatively high. The latter finding is consistent with the results of Schoumaker (2019Schoumaker ( , 2017. From a demographic perspective, such disparities can be driven by three main factors: first, differences in the population sizes of males and females, i.e., in the sex ratio, which can affect both TFR and CFR differences; second, age differences between mothers and fathers in interplay with variation in cohort sizes (affecting the TFR and the CFR); and, third, gender differences in tempo effects, which can impact gender differences in the TFR, but not in the CFR.…”