A research team demonstrates that increased levels of ozone resulting from anthropogenic air pollution can degrade insect sex pheromones, which are crucial mating signals, and thus prevent successful reproduction. The oxidizing effect of ozone causes the carbon-carbon double bonds found in the molecules of many insect pheromones to break down. Therefore, the specific chemical mating signal is rendered dysfunctional. The researchers show this effect in the vinegar fly Drosophila melanogaster and nine other species of the genus Drosophila. Most remarkably, the disrupted sexual communication also led to male flies exhibiting unusual mating behavior towards ozonated males of their own species.