Air pollution may cut number of boy births
Looking to score, fellas? The secret may be moving to a highly polluted area. Turns out air pollution may skew the ratio of female to male births in favor of the former, by altering the proportion of sperm that carry an X vs. a Y chromosome. A team of Brazilian researchers divided Sao Paulo — Brazil’s largest city, with a population of 17 million — into areas of low, medium, and high air pollution and then assessed birth registries in each area from 2001 to 2003. In neighborhoods with the worst air pollution, 49.3 percent of babies were female, versus 48.3 percent in parts of town with the cleanest air. The team calculated that 1,180 more boys would have been born if the sex ratio had been the same in both areas. Lead researcher Jorge Hallak thinks pollution may be a reproductive stress similar to war or natural disasters; when survival seems at risk, the human race produces extra girls, possibly to improve the odds for future babies. Hey, hot stuff … ensure humanity’s survival here much?
