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to alert and/or attract from long-range as well as olfactory attractants [5,14]. 

 Experiments with carbon dioxide show that near a source of carbon dioxide, 

 mosquitoes behave abnormally; this may be due to lack of other stimuli for short- 

 range attraction, or due to a tonic response of sensilla from non-intermittent release 

 of carbon dioxide [7]. These airborne attractants are detected as odor plumes. 

 Short-range attraction may be accomplished by visual cues, as by changes in 

 temperature or humidity [5,7]. Additionally, sound or wingbeat frequency is used at 

 short-range for mate location. 

 Vision 



Visual patterns on the ground generally control appetitive flight. Mosquitoes 

 will respond to dark shapes, movement, and colors preferably as visual cues; these 

 will alter the mosquito flight path [9]. Darker colors attract to a greater extent that 

 lighter colors [14]. One theory attributes vision to be used in orienting upwind flight. 

 This theory describes mosquito ability to judge windspeed by measuring its own 

 movement at specific heights [2]. For shelter-seeking mosquitoes, vision is the means 

 of site location. Visual cues also tend to be preferred over olfactory cues for nectar 

 and oviposition site location in mosquitoes. This implies a long-range use of vision 

 for these conditions, and that olfactory cues are employed for short-range with 

 respect to nectar feeding and oviposition [9]. 

 Heat 



The thermal neurosensory response can be tonic (continuous) to ambient 

 temperature or phasic (intermittent) during rapid temperature changes [4]. 



