The influence of visual landscape on the free flight behavior of the fruit fly Drosophila melanogaster

SUMMARY To study the visual cues that control steering behavior in the fruit fly Drosophila melanogaster, we reconstructed three-dimensional trajectories from images taken by stereo infrared video cameras during free flight within structured visual landscapes. Flies move through their environment using a series of straight flight segments separated by rapid turns, termed saccades, during which the fly alters course by approximately 90° in less than 100 ms. Altering the amount of background visual contrast caused significant changes in the fly’s translational velocity and saccade frequency. Between saccades, asymmetries in the estimates of optic flow induce gradual turns away from the side experiencing a greater motion stimulus, a behavior opposite to that predicted by a flight control model based upon optomotor equilibrium. To determine which features of visual motion trigger saccades, we reconstructed the visual environment from the fly’s perspective for each position in the flight trajectory. From these reconstructions, we modeled the fly’s estimation of optic flow on the basis of a two-dimensional array of Hassenstein–Reichardt elementary motion detectors and, through spatial summation, the large-field motion stimuli experienced by the fly during the course of its flight. Event-triggered averages of the large-field motion preceding each saccade suggest that image expansion is the signal that triggers each saccade. The asymmetry in output of the local motion detector array prior to each saccade influences the direction (left versus right) but not the magnitude of the rapid turn. Once initiated, visual feedback does not appear to influence saccade kinematics further. The total expansion experienced before a saccade was similar for flight within both uniform and visually textured backgrounds. In summary, our data suggest that complex behavioral patterns seen during free flight emerge from interactions between the flight control system and the visual environment.

Download Full-text

The effect of optic flow cues on honeybee flight control in wind

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2020.3051 ◽

2021 ◽

Vol 288 (1943) ◽

pp. 20203051

Author(s):

Emily Baird ◽

Norbert Boeddeker ◽

Mandyam V. Srinivasan

Keyword(s):

Flight Control ◽

Optic Flow ◽

Visual Motion ◽

Transverse Component ◽

Natural Environments ◽

Ground Speed ◽

Simple Strategy ◽

Longitudinal Optic ◽

Transverse Optic ◽

Robust Systems

To minimize the risk of colliding with the ground or other obstacles, flying animals need to control both their ground speed and ground height. This task is particularly challenging in wind, where head winds require an animal to increase its airspeed to maintain a constant ground speed and tail winds may generate negative airspeeds, rendering flight more difficult to control. In this study, we investigate how head and tail winds affect flight control in the honeybee Apis mellifera , which is known to rely on the pattern of visual motion generated across the eye—known as optic flow—to maintain constant ground speeds and heights. We find that, when provided with both longitudinal and transverse optic flow cues (in or perpendicular to the direction of flight, respectively), honeybees maintain a constant ground speed but fly lower in head winds and higher in tail winds, a response that is also observed when longitudinal optic flow cues are minimized. When the transverse component of optic flow is minimized, or when all optic flow cues are minimized, the effect of wind on ground height is abolished. We propose that the regular sidewards oscillations that the bees make as they fly may be used to extract information about the distance to the ground, independently of the longitudinal optic flow that they use for ground speed control. This computationally simple strategy could have potential uses in the development of lightweight and robust systems for guiding autonomous flying vehicles in natural environments.

Download Full-text

Ambient temperature affects free-flight performance in the fruit fly Drosophila melanogaster

Journal of Comparative Physiology B ◽

10.1007/s003600050207 ◽

1999 ◽

Vol 169 (3) ◽

pp. 165-171 ◽

Cited By ~ 38

Author(s):

F.-O. Lehmann

Keyword(s):

Drosophila Melanogaster ◽

Ambient Temperature ◽

Fruit Fly ◽

Flight Performance ◽

Free Flight

Download Full-text

FMRFa receptor stimulated Ca2+ signals alter the activity of flight modulating central dopaminergic neurons in Drosophila melanogaster

10.1101/336768 ◽

2018 ◽

Cited By ~ 1

Author(s):

Preethi Ravi ◽

Deepti Trivedi ◽

Gaiti Hasan

Keyword(s):

Drosophila Melanogaster ◽

Dopaminergic Neurons ◽

Neuronal Excitability ◽

Insect Flight ◽

Fruit Fly ◽

Egg Laying ◽

Flight Behavior ◽

Food Sources ◽

Membrane Excitability ◽

Release Channel

AbstractNeuropeptide signaling influences animal behavior by modulating neuronal activity and thus altering circuit dynamics. Insect flight is a key innate behavior that very likely requires robust neuromodulation. Cellular and molecular components that help modulate flight behavior are therefore of interest and require investigation. In a genetic RNAi screen for G-protein coupled receptors that regulate flight bout durations, we earlier identified several receptors, including the receptor for the neuropeptide FMRFa (FMRFaR). To further investigate modulation of insect flight by FMRFa we generated CRISPR-Cas9 mutants in the gene encoding the Drosophila FMRFaR. The mutants exhibit significant flight deficits with a focus in dopaminergic cells. Expression of a receptor specific RNAi in adult central dopaminergic neurons resulted in progressive loss of sustained flight. Further, genetic and cellular assays demonstrated that FMRFaR stimulates intracellular calcium signaling through the IP3R and helps maintain neuronal excitability in a subset of dopaminergic neurons for positive modulation of flight bout durations.Author summaryNeuropeptides play an important role in modulating neuronal properties such as excitability and synaptic strength and thereby influence innate behavioral outputs. In flying insects, neuromodulation of flight has been primarily attributed to monoamines. In this study, we have used the genetically amenable fruit fly, Drosophila melanogaster to identify a neuropeptide receptor that is required in adults to modulate flight behavior. We show from both knockdown and knockout studies that the neuropeptide receptor, FMRFaR, present on a few central dopaminergic neurons, modulates the duration of flight bouts. Overexpression of putative downstream molecules, the IP3R, an intracellular Ca2+-release channel, and CaMKII, a protein kinase, significantly rescue the flight deficits induced by knockdown of the FMRFaR. Our data support the idea that FMRFaR and CaMKII help maintain optimal membrane excitability of adult dopaminergic neurons required to sustain longer durations of flight bouts. We speculate that the ability to maintain longer flight bouts in natural conditions enhances the individual’s capacity to search and reach food sources as well as find sites suitable for egg laying.

Download Full-text

Limits of subjective and objective vection for ultra-high frame rate visual displays

10.1101/2020.03.19.998591 ◽

2020 ◽

Cited By ~ 1

Author(s):

Séamas Weech ◽

Sophie Kenny ◽

Claudia Martin Calderon ◽

Michael Barnett-Cowan

Keyword(s):

Optic Flow ◽

Path Length ◽

Visual Motion ◽

Postural Sway ◽

Human Perception ◽

Frame Rate ◽

Large Field ◽

Visual Displays ◽

High Frame Rate ◽

Postural Responses

AbstractLarge-field optic flow generates the illusory percept of self-motion, termed ‘vection’. Smoother visual motion displays generate a more compelling subjective sense of vection and objective postural responses, as well as a greater sense of immersiveness for the user observing the visual display. Research suggests that the function linking frame rate and vection asymptotes at 60 frames per second (FPS), but previous studies have used only moderate frame rates that do not approach the limits of human perception. Here, we measure vection using subjective and objective (mean frequency and path length of postural centre-of-pressure (COP) excursions) responses following the presentation of high-contrast optic flow stimuli at slow and fast speeds and low and ultra-high frame rates. We achieve this using a novel rendering method implemented with a projector capable of sub-millisecond temporal resolution in order to simulate refresh rates ranging from very low (15 FPS) to ultra-high frame rates (480 FPS). The results suggest that subjective vection was experienced most strongly at 60 FPS. Below and above 60 FPS, subjective vection is generally weaker, shorter, and starts later, although this pattern varied slightly according to the speed of stimuli. For objective measures, while the frequency of postural sway was unaffected by frame rate, COP path length was greatest for 480 FPS stimuli. Together, our results support diminishing returns for vection above 60 FPS and provide insight into the use of high frame rate for enhancing the user experience in visual displays.

Download Full-text

Hox dosage contributes to flight appendage morphology in Drosophila

Nature Communications ◽

10.1038/s41467-021-23293-8 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Rachel Paul ◽

Guillaume Giraud ◽

Katrin Domsch ◽

Marilyne Duffraisse ◽

Frédéric Marmigère ◽

...

Keyword(s):

Drosophila Melanogaster ◽

Differential Expression ◽

Hox Genes ◽

Expression Profiles ◽

Fruit Fly ◽

Insect Species ◽

Wing Morphology ◽

Hox Proteins ◽

Spatial Expression ◽

Flying Insects

AbstractFlying insects have invaded all the aerial space on Earth and this astonishing radiation could not have been possible without a remarkable morphological diversification of their flight appendages. Here, we show that characteristic spatial expression profiles and levels of the Hox genes Antennapedia (Antp) and Ultrabithorax (Ubx) underlie the formation of two different flight organs in the fruit fly Drosophila melanogaster. We further demonstrate that flight appendage morphology is dependent on specific Hox doses. Interestingly, we find that wing morphology from evolutionary distant four-winged insect species is also associated with a differential expression of Antp and Ubx. We propose that variation in the spatial expression profile and dosage of Hox proteins is a major determinant of flight appendage diversification in Drosophila and possibly in other insect species during evolution.

Download Full-text

Quantitative investigation reveals distinct phases in Drosophila sleep

Communications Biology ◽

10.1038/s42003-021-01883-y ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

Xiaochan Xu ◽

Wei Yang ◽

Binghui Tian ◽

Xiuwen Sui ◽

Weilai Chi ◽

...

Keyword(s):

Drosophila Melanogaster ◽

General Pattern ◽

Model Organism ◽

Infrared Camera ◽

Fruit Fly ◽

Genetic Dissection ◽

Power Law Distribution ◽

Quantitative Investigation ◽

Waking Up ◽

Set Up

AbstractThe fruit fly, Drosophila melanogaster, has been used as a model organism for the molecular and genetic dissection of sleeping behaviors. However, most previous studies were based on qualitative or semi-quantitative characterizations. Here we quantified sleep in flies. We set up an assay to continuously track the activity of flies using infrared camera, which monitored the movement of tens of flies simultaneously with high spatial and temporal resolution. We obtained accurate statistics regarding the rest and sleep patterns of single flies. Analysis of our data has revealed a general pattern of rest and sleep: the rest statistics obeyed a power law distribution and the sleep statistics obeyed an exponential distribution. Thus, a resting fly would start to move again with a probability that decreased with the time it has rested, whereas a sleeping fly would wake up with a probability independent of how long it had slept. Resting transits to sleeping at time scales of minutes. Our method allows quantitative investigations of resting and sleeping behaviors and our results provide insights for mechanisms of falling into and waking up from sleep.

Download Full-text