Toxins: An Unlikely Driver of Human Evolution

A recent article in the NYT by Carl Zimmer discusses the roll poisons may have played in our evolutionary history. The high arid altitudes of the Andes contain abnormally high levels of arsenic, leading some to believe that local populations would need to have some adaptive advantage to survive. The study published in the Society for Molecular Biology and Evolution looked at small human population in the Argentinian Andes and genotyped women from the population for 4,301,332 SNPs. They discovered that of specific variation in the gene AS2MT plays a role in the metabolization of Arsenic. This variation was disproportionately present in the Andes populations when compared to populations found outside of the arsenic-rich environment, providing the first demonstration of how toxins shape human evolution.