DOI: 10.5061/dryad.ttdz08m09
title: Diurnal and nocturnal mosquitoes escape looming threats using distinct flight strategies

description: Flying insects have evolved the ability to evade looming objects such as
 predators and swatting hands. This is particularly relevant for
 blood-feeding insects like mosquitoes that routinely need to evade
 defensive actions of their blood-hosts. To minimize the chance of being
 swatted, a mosquito can use two distinct strategies: continuously exhibit
 an unpredictable flight path or maximize its escape manoeuvrability. We
 studied how baseline flight unpredictability and escape manoeuvrability
 affects the escape performance of day-active and night-active mosquitoes
 (Aedes aegypti and Anopheles coluzzii, respectively). We used a
 multi-camera high-speed videography system to track how freely flying
 mosquitoes respond to an event-triggered rapidly approaching mechanical
 swatter, in four light conditions ranging from pitch darkness to overcast
 daylight. Results show that both species exhibit enhanced escape
 performance in their respective natural light condition (daylight for
 Aedes and dark for Anopheles). To achieve this, they show strikingly
 different behaviours. The enhanced escape performance of Anopheles at
 night is explained by their baseline unpredictable erratic flight
 behaviour, whereas the increased escape performance of Aedes in overcast
 daylight is due to their enhanced escape manoeuvres. This shows that both
 day and night active mosquitoes modify their flight behaviour in function
 of light intensity such that their escape performance is maximum in their
 natural blood-feeding light conditions, when these defensive actions by
 their blood-hosts occur most. Because Aedes and Anopheles mosquitoes are
 major vectors of several deadly human diseases, this knowledge can be used
 to optimize vector control methods for these specific species.
description: <b>Database S1:
 flight tracks of all <i>Anopheles coluzzii</i> and
 <i>Aedes aegypti</i> mosquitoes attacked by the (virtual)
 mechanical swatter, and flying in various light conditions. Related to
 STAR Methods. </b>Two<b> </b>Matlab .mat files contain
 three-dimensional tracks of all flying mosquitoes (one .mat for each
 species), described as the time<i> t</i> (s) and the spatial
 {<i>x</i>, <i>y</i>, <i>z</i>} (m)
 coordinates of the mosquito at each video frame. The coordinates are in
 meters, and in the world reference frame as defined in figure 1, with
 <i>z</i> oriented vertically up, and the origin of the
 coordinate frame at the centre of the flight arena. The trajectories were
 determined as described in the materials and methods. Metadata for each
 track includes species, age, swatter type (black or clear mesh) and mode
 (on or off), light condition, as well as temperature and humidity over
 time in the arena during each experiment. In addition, the file contains
 the kinematic of the mechanical swatter, as well as the geometry of the
 flight arena and the swatter. <b>Methods S1:
 Analysis codes.</b><b> Related to STAR Methods.
 </b>Contains all original matlab codes that were written to perform
 the analysis of the article and to generated the panels of Fig.
 1-7.<b> </b>Also contains JAGS<b> </b>modeling
 codes used for determining the Bayesian generalized linear models (B-GLM)
 in Fig. 2, 4-7. And codes used for estimating means in Fig. 2 and
 7.