JERUSALEM, March 4 (Xinhua) -- Israeli researchers have found that mosquitoes protect their eggs from predatory fish by smelling bacteria on the fish.
Bacteria are known for producing chemical signals that give information to those around them about the animal that carries them. Some animals, for instance, use pheromones, chemicals secreted in minute amounts, to communicate with the same species.
In the new study, researchers from the University of Haifa studied the role of bacteria in transferring information between different species, in this case fish and mosquitoes.
Previous studies have shown that female mosquitoes know how to identify and avoid laying their eggs in ponds containing predatory fish, as mosquitoes spend most of their lives in water from the egg stage to the pupa and are vulnerable to those predators.
According to the study published in the Journal of Animal Ecology, researchers introduced predatory fish into a pond with a disinfectant, eliminating some bacteria on the fish, and found that gravid female mosquitoes failed to sense the fish and laid eggs.
However, when in water with untreated fish, the female mosquitoes refrained from laying eggs.
In another test, bacteria on fish were introduced into spawning ponds, and gravid mosquitoes reduced egg-laying in response to a specific bacteria species, suggesting the bacteria emitted an odor associated with the fish.
The researchers said that their findings highlighted the transfer of information between predator and prey through a third species, the bacterium. It may lead to the development of an eco-friendly mosquito repellent. ■
