A study shows that air pollution is a real problem for the reproduction of certain insects such as fruit flies. This indeed causes sexual confusion in females for whom males no longer have any “sex appeal”.
Degradation of olfactory abilities
Lately, a British study showed that air pollution in rural and urban areas seemed reduce insect pollination action, including bees, moths, hoverflies and butterflies. New research published in the journal Nature Communications on March 14, 2023 and conducted by the Max Planck Institute for Chemical Ecology (Germany) highlights another problem: atmospheric pollution would also affect the reproduction of certain insects such as Drosophila type flies (or fruit flies).
According to the researchers, this is due to ozone (one of the most common pollutants in the air). Indeed, even in the case of a fairly low dose, ozone impairs olfactory abilities insects. The phenomenon particularly affects pheromones, the chemical substances responsible for social and sexual reactions in individuals of the same species.
The researchers say they conducted experiments incorporating typical ozone levels in some major cities. This made it possible to understand that males lose “sex appeal” in the eyes of females. Some males even chase other males with obviously no chance of reproductive success.
A hitherto unknown factor
Unfortunately, disruption of sexual communication by pheromones concerned nine of the ten species of fruit flies included in the study. However, scientists believe that the oxidizing effect of atmospheric pollution on the carbon chains of pheromones for several days could impact other types of insects whose reproduction also relies on pheromones. This is a new factor which could also contribute to accentuating the decline of half of the insect species at work for several decades.
Remember that before the industrial revolution, natural ozone levels in the air averaged 40 parts per billion (ppb). Today, some cities and industrial areas show rates often exceeding 200 ppb. However, the study identified significant disturbances in insect sexual communication at levels around 100 ppb.
Finally, in addition to ozone, other pollutants could exert an influence on insects. Take for example nitric oxideswhose oxidation is even faster.