The number of men compared to women in North America is fairly even. But thanks to findings of some researchers, that even distribution among the genders is not the case in tropical regions.
It seems that predicting the right sex of an unborn baby may be easier in countries that are located along the equator. According to a 2009 report from University of Georgia researcher Kristen Navara, the tropics has a higher percentage of babies born female than countries in cooler climates. Navara came to her conclusion after studying data on official national sex ratios from the Central Intelligence Agency’s World Factbook.
Though no specific explanation is given for the higher percentage of female babies than male babies in warmer climates, some speculate that it might be because women in cooler climates produce more testosterone to maintain bodily functions than women who live in warmer climates, such as those in the tropics.
