A study by the Max-Planck Institute suggests that human air pollution is negatively impacting ant society, affecting their characteristic scents. The researchers exposed ants from six species to ozone-polluted air at a dose of 100 parts per billion, on par with polluted cities. This exposure led to aggressive behavior and decreased the alkenes that help ants identify friends and enemies. In five species, this behavior affected nest-mate recognition. The study's lead author, Nan-Ji Jiang, also found that small but functional ant colonies and their larvae were exposed to urban-level ozone, which resulted in the death of larvae. The research was published in the Proceedings of the National Academy of Sciences.