Flight Behavior Research Articles

Paying attention to the man behind the curtain: Jim Simmons' contributions to bat echolocation

Echolocating big brown bats (Eptesicus fuscus) perceive their surroundings by broadcasting frequency-modulated (FM) ultrasonic pulses and processing returning echoes. These bats commonly navigate acoustically-cluttered environments, in which each broadcast is followed by multiple echoes at varying time delays and echo amplitudes. The bat must decode these echo cascades in order to create a coherent percept of its surroundings and adapt its flight and echolocation behavior in real time. Jim Simmons’ physiological and behavioral work—which continues to fuel research questions to this day—has significantly helped our understanding of how this decoding might be possible. In this talk, I will revisit some of Jim Simmons’ seminal work that contributed to our understanding of echolocation processing, and describe its influence on new generations of researchers who continue to build on Jim’s important work.

The Future of Climate Change and Ecofeminism in Barbara Kingsolver's Novels

Thematically, Flight Behavior departs from Prodigal Summer in its examination of the reality and effects of climate change. This novel focuses on those who deny or oppose the reality of climate change and its impact on their lives. The men in Flight Behavior, with the notable exception of the scientist Byron, perpetuate exploitative land use practises. This novel's emphasis on animals and their reproductive success opens up a crucial ecofeminist route. The monarchs have had to relocate their home and nesting grounds due to climate change, and their uncertain yet ominous future is mirrored by other difficult births in the novel: Dellarobia has a traumatic birthing experience with Hester's lambs as she comes to terms with the death of her and Cub's child. Optimism is what readers should take away from the two novels reviewed in this thesis. Understanding how people are connected to everything on Earth will help us revive the planet and stop exploiting people, animals, and nature for profit and pleasure. This paper's final chapter changes from Prodigal Summer's status quo to Flight Behavior's future. The third chapter examined how masculinist land practises replicated patriarchal, exploitative environmental usage and how only the novel's female characters perceived ecological alternatives. This chapter discusses the consequences of ignoring environmental exploitation and climate change. This chapter will cover denial, reality, and climate change mitigation to continue discussing realities and implications. I'll study how humans and nonhumans deny reality. Kingsolver said in an interview that others' denial inspired this novel. I'll list the middle class's environmental needs. Dellarobia becomes a pseudoscientist from a housewife. The environmental movement's butterfly conservationists in Appalachia are a parody. Dellarobia also resembles many of the ladies in chapter two who became reluctant environmentalists. Finally, hope. Dellarobia leads Kingsolver's audience to good change. The novel's ending is uncertain, but I think it's optimistic because of resistance.

Ungulates' Behavioral Responses to Humans as an Apex Predator in a Hunting-Prohibited Area of China.

Large mammals can perceive humans as predators and therefore adjust their behavior to achieve coexistence with humans. However, lack of research at sites with low hunting intensity limits our understanding of how behavioral responses of animals adapt to different predation risks by humans. At Heshun County in North China, where hunting has been banned for over three decades and only low-intensity poaching exists, we exposed two large ungulates (Siberian roe deer Capreolus pygarus and wild boar Sus scrofa) to the sounds of humans, an extant predator (leopard Panthera pardus) and a control (wind), and examined their flight responses and detection probabilities when hearing different type of sounds. Both species showed higher flight probabilities when hearing human vocalization than wind, and wild boar were even more likely to flee upon hearing human vocalization than leopard roar, suggesting the behavioral response to humans can equal or exceed that of large carnivores in these two ungulates even in an area without hunting practices. Recorded sounds had no effect on detection probability of both ungulates. Additionally, with repeated exposure to sounds, regardless of treatment, roe deer were less likely to flee and wild boars were more likely to be detected, indicating a habituation-type response to sound stimuli. We speculate that the immediate flight behavior rather than shifts in habitat use of the two species reflect the low hunting/poaching pressure at our study site and suggest further examination of physiological status and demographic dynamics of the study species to understand human influence on their long-term persistence.

Genome-wide analysis reveals novel regulators of synaptic maintenance in Drosophila.

Maintaining synaptic communication is required to preserve nervous system function as an organism ages. While much work has been accomplished to understand synapse formation and development, we understand relatively little regarding maintaining synaptic integrity throughout aging. To better understand the mechanisms responsible for maintaining synaptic structure and function, we performed an unbiased forward genetic screen to identify genes required for synapse maintenance of adult Drosophila neuromuscular junctions. Using flight behavior as a screening tool, we evaluated flight ability in 198 lines from the Drosophila Genetic Reference Panel to identify single nucleotide polymorphisms (SNPs) that are associated with a progressive loss of flight ability with age. Among the many candidate genes identified from this screen, we focus here on 10 genes with clear human homologs harboring SNPs that are most highly associated with synaptic maintenance. Functional validation of these genes using mutant alleles revealed a progressive loss of synaptic structural integrity. Tissue-specific knockdown of these genes using RNA interference (RNAi) uncovered important roles for these genes in either presynaptic motor neurons, postsynaptic muscles, or associated glial cells, highlighting the importance of each component of tripartite synapses. These results offer greater insight into the mechanisms responsible for maintaining structural and functional integrity of synapses with age.

Induction of flight via midbrain projections to the cuneiform nucleus.

The dorsal periaqueductal gray is a midbrain structure implicated in the control of defensive behaviors and the processing of painful stimuli. Electrical stimulation or optogenetic activation of excitatory neurons in dorsal periaqueductal gray results in freezing or flight behavior at low and high intensity, respectively. However, the output structures that mediate these defensive behaviors remain unconfirmed. Here we carried out a targeted classification of neuron types in dorsal periaqueductal gray using multiplex in situ sequencing and then applied cell-type and projection-specific optogenetic stimulation to identify projections from dorsal periaqueductal grey to the cuneiform nucleus that promoted goal-directed flight behavior. These data confirmed that descending outputs from dorsal periaqueductal gray serve as a trigger for directed escape behavior.

A lifetime track of a griffon vulture: The moving story of Rehovot (Y64).

A lifetime track of a griffon vulture: The moving story of Rehovot (Y64).

Graded Atmospheres of Volatile Pyrethroid Overlaid on Host Cues Can Be Established and Quantified Within a Novel Flight Chamber for Mosquito Behavior Studies.

Spatial repellents are emerging as a promising approach to reduce vector-disease burden; however, the evolution of genetically resistant mosquitoes decreases repellent efficacy. The development of flight chambers to investigate spatial repellent application techniques is vital for sustainable mosquito control. We present an air-dilution chamber as a novel bioassay to study mosquito flight behavior responses to chemical gradients of the volatile, pyrethroid transfluthrin (TF). Air dilution was used to simulate a larger environment of stable concentration gradients verified with carbon dioxide (CO2) which was homogenously delivered and measured across the chamber to achieve a 5× inlet/outlet [CO2] ratio with 0.17 m/s outlet velocity. Female Aedes (Ae.) aegypti (Diptera: Culicidae, Linnaeus, 1762) were exposed to volatilized TF paired with heat, CO2, and Biogents-Sweetscent host-cues. Tandem solvent extraction-gas chromatography-mass spectrometry (SE-GC-MS) was used to quantify air samples taken during TF emanations with a limit of detection (LOD) and quantification (LOQ) of 2 ± 1 and 5 ± 2 parts-per-trillion (ppt) TF, respectively. Homogenous air diluted emanation of the spatial repellent TF was at least twice that of the 5× CO2 gradient with the same air flow in the chamber. The airborne TF concentrations the mosquitoes were exposed to range from 1 to 170 ppt. Video recordings of mosquito behavior during host-cues exposure revealed increased inlet activity, while exposure to TF protected host resulted in decreased inlet activity over time with inlet-outlet mosquito positional variation. This novel flight chamber design can simulate 'long'-range exposure with simultaneous quantitation of airborne spatial repellent to understand dose-dependent effects on mosquito behavior.

Energy Utilization and Flight Muscle Development in Chrysoperla sinica (Neuroptera: Chrysopidae) Female Adults: Relationship With Age and Flight Behavior.

We investigated the accumulation of energy substances, dynamics of flight muscle development, changes in energy substances accumulation, and flight muscle structure after flight activities in female adults of the green lacewing Chrysoperla sinica (Tjeder), a common natural enemy of various insect pests in China. Virgin individuals were chosen at 24, 72, and 120 h after eclosion for energy substance determination and flight muscle observation in this study. Individuals with strong flight ability at 72 h after eclosion were selected for tethered flight assays, followed by detection of energy substances, and flight muscle observation. The results showed that virgin female adults had the highest fat content 72 h after eclosion. Sarcomere length and myofibril diameter changed significantly with age, with the lowest at 24 h after eclosion. With an increase in flight distance, the fat and glycogen contents, sarcomere length, and volume fraction of the transverse tubular system (T-system) decreased and myofibril diameters increased. The volume fraction of the mitochondria did not significantly change, but the structure of the mitochondrial membrane was destroyed, inclusions were reduced, and cavities appeared. The reserves of energy substances, especially lipids, are closely related to the flight ability of C. sinica. The observational results of both flight muscle structure and morphology of mitochondria build a strong relationship with flight behavior. This research should help reveal the regulatory mechanism of flight activity of C. sinica.

Window films increase avoidance of collisions by birds but only when applied to external compared with internal surfaces of windows.

Window collisions are one of the largest human-caused causes of avian mortality in built environments and, therefore, cause population declines that can be a significant conservation issue. Applications of visibly noticeable films, patterns, and decals on the external surfaces of windows have been associated with reductions in both window collisions and avian mortality. It is often logistically difficult and economically prohibitive to apply these films and decals to external surfaces, especially if the windows are above the first floor of a building. Therefore, there is interest and incentive to apply the products to internal surfaces that are much easier to reach and maintain. However, there is debate as to whether application to the internal surface of windows renders any collision-reduction benefit, as the patterns on the films and decals may not be sufficiently visible to birds. To address this knowledge gap, we performed the first experimental study to compare the effectiveness of two distinct window films when applied to either the internal or external surface of double-glazed windows. Specifically, we assessed whether Haverkamp and BirdShades window film products were effective in promoting the avoidance of window collisions (and by inference, a reduction of collisions) by zebra finches through controlled aviary flight trials employing a repeated-measures design that allowed us to isolate the effect of the window treatments on avoidance flight behaviors. We chose these two products because they engage with different wavelengths of light (and by inference, colors) visible to many songbirds: the BirdShades film is visible in the ultraviolet (shorter wavelength) range, while the Haverkamp film includes signals in the orange (longer wavelength) range. We found consistent evidence that, when applied to the external surface of windows, the BirdShades product resulted in reduced likelihood of collision and there was marginal evidence of this effect with the Haverkamp film. Specifically, in our collision avoidance trials, BirdShades increased window avoidance by 47% and the Haverkamp increased avoidance by 39%. However, neither product was effective when the films were applied to the internal surface of windows. Hence, it is imperative that installers apply these products to exterior surfaces of windows to render their protective benefits and reduce the risk of daytime window collision.

Non-uniform spatial sampling by individuals in midge swarms.

Individual animals engaged in collective behaviour can interchange their relative positions on a wide range of time scales. In situations where some regions of the group are more desirable, it is thought that more fit individuals will preferentially occupy the more favourable locations. However, this notion is difficult to test for animal groups like insect swarms that fluctuate rapidly and display little apparent structure. Here, we study the way that individuals in mating swarms of the non-biting midge Chironomus riparius sample the space available to them. We use Voronoi tessellation to define different regions of the swarm in a dynamic way, and show that midges indeed sample the swarm non-uniformly. However, individuals that preferentially reside in the interior or exterior of the swarm do not display statistically distinct flight behaviour, suggesting that differences in fitness must be assessed in a different way. Nevertheless, our results indicate that midge swarms are not random configurations of individuals but rather possess non-trivial internal structure.

Primary care of Ukrainian refugees

Since the beginning of the war in Ukraine, more than 7.6million people from Ukraine have been registered as refugees in European countries. In Germany, the number is estimated to be more than 1million. These refugees may have different health needs than German patients due to differences in the health care system, disease prevalence, preventive measures, health behavior, and experiences of flight. However, general practitioners (GPs) have hardly been prepared for the contact. For the first time, challenges in the treatment of Ukrainian refugees and support needs of German GPs were determined. In July and August 2022, across-sectional study among GPs in Germany was conducted using an online survey. A total of 82GPs participated with aresponse rate of 16.0%; 52of the participating GPs had treated Ukrainian refugees in the previous 2weeks. In all, 75.0% of them reported difficulties or peculiarities in care, especially in communication (61.5%), due to lack of information about previous illnesses (34.6%), and expectations of services to be provided (30.8%). Of the 82participants, 59.8% reported aneed for multilingual information for patients, especially about the German health care system, help with mental health problems, contact points, and differences in the use of medications. Information for the practice team is needed in 37.8% of cases, especially on possibilities in case of language barriers, vaccination coverage in Ukraine, and dealing with missing vaccination records as well as drug lists. Due to the new situation of Ukrainian refugees in Germany and the mentioned barriers, GPs should be supported in care. Information for practice teams as well as their networking with psychotherapeutic offers, contact points, drug databases, and regional interpreter services are urgently needed. However, multilingual information for Ukrainian patients should be disseminated in order to relieve the burden on practices, which have been under great strain, and to ensure continuity and quality of care.

Optic flow enrichment via Drosophila head and retina motions to support inflight position regulation

Developing a functional description of the neural control circuits and visual feedback paths underlying insect flight behaviors is an active research area. Feedback controllers incorporating engineering models of the insect visual system outputs have described some flight behaviors, yet they do not explain how insects are able to stabilize their body position relative to nearby targets such as neighbors or forage sources, especially in challenging environments in which optic flow is poor. The insect experimental community is simultaneously recording a growing library of in-flight head and eye motions that may be linked to increased perception. This study develops a quantitative model of the optic flow experienced by a flying insect or robot during head yawing rotations (distinct from lateral peering motions in previous work) with a single other target in view. This study then applies a model of insect visuomotor feedback to show via analysis and simulation of five species that these head motions sufficiently enrich the optic flow and that the output feedback can provide relative position regulation relative to the single target (asymptotic stability). In the simplifying case of pure rotation relative to the body, theoretical analysis provides a stronger stability guarantee. The results are shown to be robust to anatomical neck angle limits and body vibrations, persist with more detailed Drosophila lateral-directional flight dynamics simulations, and generalize to recent retinal motion studies. Together, these results suggest that the optic flow enrichment provided by head or pseudopupil rotation could be used in an insect’s neural processing circuit to enable position regulation.

Teaching Climate Change Science with the Humanities and Global Perspectives

Teaching Climate Change Science with the Humanities and Global Perspectives

Gap selection and steering during obstacle avoidance in pigeons.

The ability of birds to fly through cluttered environments has inspired biologists interested in understanding its underlying mechanisms, and engineers interested in applying its underpinning principles. To analyse this problem empirically, we break it down into two distinct, but related, questions: How do birds select which gaps to aim for? And how do they steer through them? We answered these questions using a combined experimental and modelling approach, in which we released pigeons (Columbia livia domestica) inside a large hall with an open exit separated from the release point by a curtain creating two vertical gaps - one of which was obstructed by an obstacle. We tracked the birds using a high-speed motion capture system, and found that their gap choice seemed to be biased by their intrinsic handedness, rather than determined by extrinsic cues such as the size of the gap or its alignment with the destination. We modelled the pigeons' steering behaviour algorithmically by simulating their flight trajectories under a set of six candidate guidance laws, including those used previously to model target-oriented flight behaviours in birds. We found that their flights were best modelled by delayed proportional navigation commanding turning in proportion to the angular rate of the line-of-sight from the pigeon to the midpoint of the gap. Our results are consistent with this being a two-phase behaviour, in which the pigeon heads forward from the release point before steering towards the midpoint of whichever gap it chooses to aim for under closed-loop guidance. Our findings have implications for the sensorimotor mechanisms that underlie clutter negotiation in birds, uniting this with other kinds of target-oriented behaviours including aerial pursuit.

Effects of Flight on Reproductive Development in Long-Winged Female Crickets (Velarifictorus aspersus Walker; Orthoptera: Gryllidae) with Differences in Flight Behavior.

A trade-off between the capacity for flight and reproduction has been documented extensively in wing polymorphic female insects, thereby supporting the possible fitness gain due to flightlessness. However, most of these studies were conducted without considering the effect of flight behavior. In the present study, we assessed the flight duration by long-winged (LW) females in the cricket species Velarifictorus aspersus on different days after adult emergence and examined the effect of flight on ovarian development in LW females with different flight capacities. Our results showed that the flight capacity increased with age and peaked after 5 days. In addition, the flight capacity varied among individuals, where most LW females could only take short flights (sustained flight time < 10 min) and only a few individuals could take long flights (sustained flight time > 20 min). In LW female crickets demonstrating only short flights, repeated flying for 30 or 60 min significantly promoted reproductive development. However, in those capable of long flights, reproductive development was affected only after a flight of 60 min. The flight muscles degraded after the start of rapid reproduction in those with both short and long flights. Our results indicated that the critical flight time for switching from flight to reproduction varies among LW V. aspersus female crickets with polymorphic flight behavior.

WITHDRAWN: Determination of the statistical distribution of drag and lift coefficients of refuse derived fuel by computer vision

This research investigates the flight behavior of refuse-derived fuel (RDF) in a drop shaft using Computer Vision to obtain statistical data on the aerodynamic properties of the particles. Methods to determine 3D geometry models of complex-shaped particles by photogrammetry and to obtain time resolved particle positions and velocities are described. Furthermore, an approach to obtain the frequency distribution of drag and lift coefficients from photogrammetric analysis and drop shaft experiments is presented. The image evaluation is based on algorithms of the open-source libraries OpenCV, COLMAP as well as MeshLab and Open3D. The precision of the system is validated employing model particles with known geometry. The 3D particle models overestimate the particle surface area by 4.58 %, the position detection works with a mean deviation of 2.73 %. The average sink rate is calculated with an accuracy of 4.87 % and the drag coefficient with an accuracy of 2.08 %. Finally, the frequency distribution of four RDF fractions, namely, textiles, cardboard, 3D plastic particles and plastic foils are presented.

Thermal soaring over the North Sea and implications for wind farm interactions

Seabirds use several flight modes at sea, including thermal soaring, in which thermal uplift is used to gain altitude and save energy. An increase in flight altitude may have consequences for wind farm interactions if it results in birds spending more time within the rotor-swept zone (RSZ). To understand conditions under which thermal soaring occurs and potential implications for wind farm interactions, we investigated thermal soaring in relation to atmospheric conditions in June and July at 2 study areas in the North Sea, west and north of the Dutch coast. We developed algorithms that identified thermal soaring in GPS tracks of lesser black-backed gulls Larus fuscus and radar tracks of seabirds. By combining species-specific 3-dimensional information on flight behaviour from bio-logging with the continuous spatiotemporal coverage of radar positioned at wind parks, we obtained a more comprehensive overview of thermal soaring at sea than either method would obtain alone. Our results showed that birds flew at higher altitudes during thermal soaring than non-soaring flight, increasing the proportion of flight time within the RSZ. Thermal soaring occurred inside offshore wind farms to a similar degree as outside. Thermal soaring was positively correlated with positive temperature differences (ΔT) between sea surface and air (at 2 m above sea level), and north and north-westerly winds. We show that the probability of thermal soaring over the North Sea, inside and outside wind farms, increases with larger temperature differences, resulting in increased time spent within the RSZ and an increased collision risk for seabirds.

Wind driven effects on the fine-scale flight behaviour of dynamic soaring wandering albatrosses

Wandering albatrosses Diomedea exulans are among the largest flying birds. Their energy-efficient dynamic soaring flight allows them to travel large distances by exploiting the gradient in wind strength above the sea surface. We used bio-logging devices to study the dynamic soaring flight behaviour of wandering albatrosses, deriving roll (bank) angles from video and tri-axial magnetometers, and flapping events from tri-axial accelerometers. Albatrosses mostly experienced westerly winds coming from their left during outbound flights from their colonies and from their right when returning. They compensated for differences in wind speed by varying their roll angles and predominantly turning into the wind, resulting in a net displacement that was perpendicular to the wind. Flapping flight was influenced by wind speed and direction, with birds spending more time flapping in light winds and in head winds. Flapping often occurred at the upper turn of the dynamic soaring cycle, a stage previously considered devoid of flapping. There was also evidence of sexual differences in flight behaviour, with females flapping less than males. Males almost exclusively take off into head winds, whereas females utilized cross winds as well. These results add to our knowledge of dynamic soaring and show how albatrosses react to their wind fields at a fine scale.

Deployment of a 5G Networking Module for Robotics and IoT Applications

Currently, available 5G modules are mostly installed on larger development kits, require a microcontroller as middleware, and thus do not have a compatible interface that enables simple integration into systems, machines, or robotics as a plug-and-play solution, similar to a Wi-Fi USB stick. For the application of 5G in the field of robotics, however, it is important to have modules that are as light and small as possible, provide easy integration, and fully deliver the capabilities of 5G. Therefore, our paper presents a small and lightweight 5G communication adapter in which a 5G-radio module is mounted on an M2 carrier board and can be connected via USB to any compatible device. For testing purposes, the communication adapter is presented in an Unmanned Aerial Systems (UAV) application that depends on time-critical communication. The test environment is equipped with motion capture cameras that are used to determine the position of the UAV. ROS2 acts as middleware for communication between the various interfaces, specifically the development computer, the drone's companion computer, and the motion capture system. Subsequently, the measured communication values and resulting flight behavior are presented in detail. As a result of the data collected, the resulting benefits, limitations, and possible improvements to the UAV application and high-speed robotics applications using 5G technology are discussed.

The Lateral and Directional Stability Behavior for Two Aircraft Models

The current study looks at flight behavior in lateral and directional motion.The investigation involves setting up the aircraft under an equilibrium condition with a small disturbance applied to it. Plotting the side slip angle, roll angle, and yaw angle with respect to time in the presence of disturbances can be used to investigate flight behavior in lateral and directional motion. Here the disturbance can be simulated by the movement of the aileron or rudder, in which these two control surfaces can be designed to move in a single impulse or multiple impulse disturbance mode. These two disturbance modes are used on the Beechcraft 99 and Cessna T37 aircraft. Both impulse disturbance models are used for the aileron and the rudder. However, in the current work, the Beechcraft 99 receives a single impulse, whereas the Cessna T37 receives multiple impulses. The implementation of such disturbances found that the Beechcraft 99 represented the aircraft that would be able to go back to its initial condition in response to a single impulse disturbance modewhile the Cessna T37 aircraft requires a little more time to return to its original yaw angle. Following the implementation of these twotypes of disturbances, it was discovered that each aircraft has the ability to return to its initial condition, but at varying times to reach its steady state solution.