Mosquitos Use Sense of Smell to Pinpoint Prey, Study

A new study has revealed that mosquitos possess tiny sensory powers that enable them to sniff out targets that include animals and humans.

Mosquitoes use visual, thermal and olfactory cues with great precision to home in on their targets.

During the study, scientists discovered that mosquitos were drawn to the carbon dioxide (CO2) plume exhaled by human beings and other animals.

The insect then goes on to use other cues like body heat and vision to zero in on its prey.

For the study, the researchers injected a high concentration of carbon dioxide into a tunnel that was designed to mimic the breath of a human.

During the same experiment, the researchers also injected background air with a low concentration of CO2.

With the concentrated CO2, the mosquitoes followed them down the tunnel but did not repeat that behaviour when low concentration of CO2 was introduced.

"The new part that we found is that the CO2 plume increases the likelihood that they will fly toward an object".

"That means that they smell the CO2, then they leave the plume, and several seconds later they continue flying toward this little object. So you could think of it as a type of memory or lasting effect," the researchers explained in a paper that appeared in the journal Current Biology.

In a separate experiment, the mosquitos were also found to be attracted visually to objects.

"A mosquito can see a visual feature from much further away so that happens first. Only when the mosquito gets closer does it detect an object's thermal signature," van Breugel said.

"Till date, very little was known about what a host looks like to the mosquito and how a mosquito decides where to land and begin to feed till now," said biologist Jeff Riffell from University of Washington, co-author on the paper.