If you ever thought swatting at mosquitos was an exercise in futility and more on humility, keep swatting. A new study showed that the blood-suckers have a preference for hosts that are less aggressive.
The way in which the Aedes aegypti mosquitos, a.k.a. yellow fever mosquitos, choose or avoid their prey depends on olfactory association with movement. Researchers exposed the bugs to host odors with "mechanical perturbations," like swatting or shivering.
Repetitive negative perturbations associated with host odors signaled danger for the bugs, according to a study published in Current Biology.
The scents emitted by humans and other hosts are complex mixtures of hundreds of odorants, making it difficult to identify which features the mosquitoes might be using to learn the association. We therefore examined the learning capabilities of mosquitoes to single odorants, several of which are emitted from hosts.
The researchers used octenol to learn how mosquitos intuitively associated between "shock and a single host-related odorant." 24-hours later, the mosquitos remembered the association between the defensive swatter and the control odor.
For the mosquitos, learning to avoid the swatters decides their fate. Chloé Lahondère, one of the researchers from Virginia Tech said:
Defending yourself against mosquitoes is helpful, whether or not you manage to hit the mosquito.
Who needs repellent when you've got arms? The report highlighted:
Host defensive behavior is a major source of mortality for mosquitoes, with hosts operating as both predator and prey. In addition, within a host species, there is strong variation in which individuals are bitten. The ability by mosquitoes to possibly learn which individuals are more, or less, defensive, will have strong fitness consequences for the mosquitoes.
Although it's not understood how the vicious attackers choose certain human hosts, constant swatting will identify you as a threat and will keep you from becoming their dinner.
Unfortunately, there is no way of knowing exactly what attracts a mosquito to a particular human — individuals are made up of unique molecular cocktails that include combinations of more than 400 chemicals. However, we now know that mosquitoes are able to learn odors emitted by their host and avoid those that were more defensive.
But the key to the researchers' findings was dopamine. The mosquitos modified with the lack of dopamine receptors weren't as responsive to learning host odors.
Lahondère added:
Now that we have a better understanding of what the mosquitoes are capable of, we need to investigate how to apply this knowledge to refine our control strategies and fight more efficiently against the disease that these mosquitoes transmit,
Clément Vinauger, an assistant professor of biochemistry in Virginia Tech, discussed how the new information from the research could help control the pesky bloodsuckers.
Understanding these mechanisms of mosquito learning and preferences may provide new tools for mosquito control. For example, we could target mosquitoes' ability to learn and either impair it or exploit it to our advantage.
Spoken like a pro.
Happy swatting, folks. It works.
H/T - Mashable, USAtoday, CurrentBiology
