Meeting Abstract
In order to produce progeny female mosquitoes require proteins and nutrients found in our blood. This food is hidden under the skin of mobile and defensive vertebrate hosts. In response, mosquitoes have evolved the ability to navigate around hosts at close range while avoiding their defensive and antiparasitic behaviors. It is well known that invertebrates display escape behaviors in response to visual, predator-like, looming stimuli. In locusts and fruit flies a subset of neurons are specialized in the encoding of looming stimuli and descending pathways control these escape responses. However, in spite of great epidemiological relevance, very little is known about how mosquitoes evade their predators, as well as swatting from their hosts. As a first step towards bridging this knowledge gap, we combined behavioral and molecular approaches to analyze the responses of Aedes aegypti females to looming visual stimuli. In a first set of experiments we used an LED arena to introduce looming, predator-like stimuli to mosquitoes that were either landed, in free flight, or in tethered flight. Results from these experiments allowed us to characterize mosquitoes’ escape responses and determine the angles and distances to the stimuli most likely to trigger an escape response under different behavioral contexts. Next, we relied on molecular and imaging approaches to investigate the underlying neural mechanisms supporting this behavior. The significance of these results will be discussed relative to the design of control tools.
