Location: Insect Behavior and Biocontrol ResearchTitle: Effect of past oviposition experience on future oviposition site selectivity in the mosquito Aedes aegypti Author
|Ruktanonchai, Nick - University Of Florida|
|Allan, Sandra - Sandy|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 1/31/2013
Publication Date: N/A
Technical Abstract: Mosquitoes exhibit specific preferences when searching for a suitable aquatic habitat for oviposition (egglaying). Taking advantage of these preferences, oviposition repellents and attractants have been developed and employed to reduce populations of medically-significant mosquito species by drawing mosquitoes into traps or keeping mosquitoes away from human without necessarily affecting fitness. These controls can help reduce local burden of mosquito-borne disease, as most mosquito-borne disease transmission occurs near aquatic habitat where eggs are laid. Previous studies have suggested that preferences for egglaying sites and egglaying behavior may be highly plastic, however, changing based on an individual’s previous exposure to repellents and attractants, which may influence how these chemicals affect oviposition patterns. In this study, we examine a previously unexplored avenue of adaptation in oviposition behavior to environmental experience, by testing whether past experience with aquatic habitat influences future choosiness. Mosquitoes do not necessarily have any knowledge of the aquatic habitats that are available in an environment. As a result, if only repellent aquatic habitats are encountered, it becomes increasingly likely that most aquatic habitats in the area are repellent. In these environments, it becomes advantageous for mosquitoes to become less choosy, and lay eggs in typically repellent waters. To test whether this mode of behavioral adaptation occurs, we compared the choosiness of mosquitoes that have a previous experience with an attractive aquatic habitat, a repellent aquatic habitat, and no aquatic habitats whatsoever. We then presented these mosquitoes with a repellent aquatic habitat in a wind tunnel, and recorded the proportion of eggs that were laid in the repellent waters. Mosquitoes that had a previous experience with repellent waters laid a significantly higher proportion of eggs in the repellent aquatic habitat (23.7%) than mosquitoes with an experience with attractive aquatic habitats (6.8%) or mosquitoes with no previous experience (13.7%). These results suggest that mosquitoes may be informing future oviposition decisions with past experiences with aquatic habitats, suggesting a potential novel mechanism of learning employed by mosquitoes. If mosquitoes are learning via this mechanism, then large-scale control measures that significantly alter the environment (such as large-scale chemical treatment campaigns) may result in unexpected changes in mosquito oviposition behavior, such as a willingness to lay eggs in waters treated with repellents.