According to a recent study, air pollution is hindering the mating of fruit flies by impeding females’ ability to recognize the scent of males.
Researchers have stated that female fruit flies rely on the pheromones emitted by males to select them for mating. However, due to ozone pollution, the ability of males to emit their distinctive scent has been disrupted.
The study demonstrates how polluted air is impeding the reproductive process of fruit flies and other insects, potentially causing a decrease in their population.
Markus Knaden, the lead author of the study published in the journal Nature Communications, stated that while the reasons for the decline in insects were previously attributed to pesticide use and habitat loss, it is important to also consider oxygen pollutants. Knaden, who is an evolutionary neuroethology researcher at the Max Planck Institute, added that this factor should be taken into account in our understanding of insect decline.
The basis of this study is the examination of how insects perceive the scent of flowers under conditions of increased ozone levels.
The Knaden team conducted experiments on nine distinct species of Drosophila fruit flies. Half of the males from each species were subjected to an environment with clean air, while the other half were exposed to an atmosphere with ozone levels of 100 parts per billion.
The researchers found that male fruit flies exposed to an atmosphere with elevated ozone levels emitted fewer pheromones and experienced difficulty in attracting female mates.
Knaden stated that when male flies were exposed to ozone, it took them significantly longer to persuade females to mate.
Furthermore, according to Knaden, emitting pheromones also helps males to repel other males from attempting to mate with them. However, when exposed to ozone, males emitted fewer pheromones, which caused them to smell less masculine and resulted in an increase in male-male mating attempts.
The researcher further explained that in a laboratory setting, it may not be critical if males have to wait a bit longer to mate or if they accidentally court other males. However, in the field, there is significant selection pressure, and the flies must be efficient in finding a female as quickly as possible, copulating, and fertilizing her eggs before predators can kill them.
Knaden emphasized that nature will be greatly impacted by this, as ozone is just one of several pollutants in the environment that can have this effect.