The little annoying and disease-carrying insects, mosquitoes, are associating near-death experiences with scent and will avoid future interactions with the ‘danger’.
A study published in ‘Current Biology’ reveals an astonishing and important aspect of mosquitoes. More specifically, scientists have noticed that mosquitoes are remembering near-death experiences and avoid to come again in those situations by associating the danger with the scent.
An experiment like Pavlov’s has been conducted
Jeff Riffell, a neuroecologist at the University of Washington, used a classical conditioning system, as Pavlov did with his dogs, to observe if mosquitoes can learn, instinctually, to stay away from dangerous experiences by associating them with their scent.
Mosquitoes are attracted by the smell of their ‘victims’ and specifically enjoy the humans’ scent. Knowing that aspects about mosquitoes, Riffell exposed mosquitoes to disturbing vibrations that mimicked the arm slapping of when we are trying to kill a mosquito that feeds on our blood.
After repeating the vibrations for 20 minutes, Riffell observed that mosquitoes avoided to return and feed on the same ‘target’ for 24 hours.
Dopamine is the key chemical
Riffell and his team explained that the brain chemical dopamine is linked with associations the brain makes, so they made another similar test on mosquitoes with disabled dopamine channels. The result was that, in the absence of dopamine, the mosquitoes can’t learn, therefore can’t associate danger with the smell.
This new discovery may represent the opening of new possibilities for the insecticides and repellents industry’s products which could now include, besides regular substances, compounds that trigger the avoidance in mosquitoes.
Not all mosquitoes species can be taught to avoid dangers
If the regular mosquitoes can learn to avoid humans that threaten them, West Nile mosquitoes (those who transmit the West Nile virus) have birds as their favorite meal. However, these mosquitoes will turn to feeding on humans, when birds are not available.
Unfortunately, West Nile mosquitoes didn’t show the same learning abilities as the other mosquitoes.
Riffell and his team will keep researching before creating new repellents but, in the meantime, they recommend people to pose as threats to mosquitoes because these annoying insects will learn you and avoid you.