Arsenic-Based Life in Mono Lake

In 2010, a NASA press conference claimed bacteria from Mono Lake could substitute arsenic for phosphorus in its DNA, suggesting an alternative biochemistry essential to life. Subsequent studies analyzed over 50 bacterial strains and conclusively showed the microbe required trace phosphorus at concentrations below 1 μM, which it extracted from impurities in the arsenic source. This corrective evidence is more thorough than the OPERA experiment's single-cable fix, as it involved multiple independent labs over several years. The arsenic-life affair remains a textbook case of how extraordinary claims, when mismatched with robust replication, can mislead the public and scientific community alike.