Mosquitoes can rapidly learn and recall Hosts’ smells, swats

Mosquitoes can rapidly learn and remember the smells of hosts, a study suggests. Dopamine is a key mediator of this process. Hosts who swat at mosquitoes or perform other defensive behaviours may be abandoned, no matter how sweet they are, according to the study. 

Mosquitoes develop preferences for a particular vertebrate host species, and within that population, certain individuals, they said. However the study also proved that even if an individual is deemed delicious smelling a mosquitos preference can shift if that persons smell is associated with an unpleasant sensation. 

The researchers said mosquitoes exhibit a trait known as aversive learning by training female seeds aegypti mosquitoes to associate odours with unpleasant shocks and vibrants. 

24 hours later the same mosquitos were assessed in a Y maze olfactometer in which they had to fly upwind and choose between the once preferred human body odour and a control odour. The mosquitoes avoided the human body odour suggesting that they had been successfully trained.