1
|
Hooper ML, Scherl I, Gharib M. Bio-inspired compensatory strategies for damage to flapping robotic propulsors. J R Soc Interface 2024; 21:20240141. [PMID: 38955227 DOI: 10.1098/rsif.2024.0141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2024] [Accepted: 06/11/2024] [Indexed: 07/04/2024] Open
Abstract
Natural swimmers and flyers can fully recover from catastrophic propulsor damage by altering stroke mechanics: some fish can lose even 76% of their propulsive surface without loss of thrust. We consider applying these principles to enable robotic flapping propulsors to autonomously repair functionality. However, direct transference of these alterations from an organism to a robotic flapping propulsor may be suboptimal owing to irrelevant evolutionary pressures. Instead, we use machine learning techniques to compare these alterations with those optimal for a robotic system. We implement an online artificial evolution with hardware-in-the-loop, performing experimental evaluations with a flexible plate. To recoup thrust, the learned strategy increased amplitude, frequency and angle of attack (AOA) amplitude, and phase-shifted AOA by approximately 110°. Only amplitude increase is reported by most fish literature. When recovering side force, we find that force direction is correlated with AOA. No clear amplitude or frequency trend is found, whereas frequency increases in most insect literature. These results suggest that how mechanical flapping propulsors most efficiently adjust to damage may not align with natural swimmers and flyers.
Collapse
Affiliation(s)
- M L Hooper
- Graduate Aerospace Laboratories, Division of Engineering and Applied Science, California Institute of Technology , Pasadena, CA, USA
| | - I Scherl
- Department of Mechanical and Civil Engineering, Division of Engineering and Applied Science, California Institute of Technology , Pasadena, CA, USA
| | - M Gharib
- Graduate Aerospace Laboratories, Division of Engineering and Applied Science, California Institute of Technology , Pasadena, CA, USA
| |
Collapse
|
2
|
Ehweiner A, Duch C, Brembs B. Wings of Change: aPKC/FoxP-dependent plasticity in steering motor neurons underlies operant self-learning in Drosophila. F1000Res 2024; 13:116. [PMID: 38779314 PMCID: PMC11109550 DOI: 10.12688/f1000research.146347.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 05/31/2024] [Indexed: 05/25/2024] Open
Abstract
Background Motor learning is central to human existence, such as learning to speak or walk, sports moves, or rehabilitation after injury. Evidence suggests that all forms of motor learning share an evolutionarily conserved molecular plasticity pathway. Here, we present novel insights into the neural processes underlying operant self-learning, a form of motor learning in the fruit fly Drosophila. Methods We operantly trained wild type and transgenic Drosophila fruit flies, tethered at the torque meter, in a motor learning task that required them to initiate and maintain turning maneuvers around their vertical body axis (yaw torque). We combined this behavioral experiment with transgenic peptide expression, CRISPR/Cas9-mediated, spatio-temporally controlled gene knock-out and confocal microscopy. Results We find that expression of atypical protein kinase C (aPKC) in direct wing steering motoneurons co-expressing the transcription factor FoxP is necessary for this type of motor learning and that aPKC likely acts via non-canonical pathways. We also found that it takes more than a week for CRISPR/Cas9-mediated knockout of FoxP in adult animals to impair motor learning, suggesting that adult FoxP expression is required for operant self-learning. Conclusions Our experiments suggest that, for operant self-learning, a type of motor learning in Drosophila, co-expression of atypical protein kinase C (aPKC) and the transcription factor FoxP is necessary in direct wing steering motoneurons. Some of these neurons control the wing beat amplitude when generating optomotor responses, and we have discovered modulation of optomotor behavior after operant self-learning. We also discovered that aPKC likely acts via non-canonical pathways and that FoxP expression is also required in adult flies.
Collapse
Affiliation(s)
- Andreas Ehweiner
- Institut für Zoologie - Neurogenetik, Universität Regensburg, Regensburg, Bavaria, 93040, Germany
| | - Carsten Duch
- Institute of Developmental Biology and Neurobiology (iDN), Johannes Gutenberg Universitat Mainz, Mainz, Rhineland-Palatinate, Germany
| | - Björn Brembs
- Institut für Zoologie - Neurogenetik, Universität Regensburg, Regensburg, Bavaria, 93040, Germany
| |
Collapse
|
3
|
Noda R, Nakata T, Liu H. Effect of Hindwings on the Aerodynamics and Passive Dynamic Stability of a Hovering Hawkmoth. Biomimetics (Basel) 2023; 8:578. [PMID: 38132518 PMCID: PMC10741636 DOI: 10.3390/biomimetics8080578] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Revised: 11/17/2023] [Accepted: 11/24/2023] [Indexed: 12/23/2023] Open
Abstract
Insects are able to fly stably in the complex environment of the various gusts that occur in nature. In addition, many insects suffer wing damage in their lives, but many species of insects are capable of flying without their hindwings. Here, we evaluated the effect of hindwings on aerodynamics using a Navier-Stokes-based numerical model, and then the passive dynamic stability was evaluated by coupling the equation of motion in three degrees of freedom with the aerodynamic forces estimated by the CFD solver under large and small perturbation conditions. In terms of aerodynamic effects, the presence of the hindwings slightly reduces the efficiency for lift generation but enhances the partial LEV circulation and increases the downwash around the wing root. In terms of thrust, increasing the wing area around the hindwing region increases the thrust, and the relationship is almost proportional at the cycle-averaged value. The passive dynamic stability was not clearly affected by the presence of the hindwings, but the stability was slightly improved depending on the perturbation direction. These results may be useful for the integrated design of wing geometry and flight control systems in the development of flapping-winged micro air vehicles.
Collapse
Affiliation(s)
- Ryusuke Noda
- Department of Mechanical Engineering, Tokyo University of Technology, 1404-1 Katakura-cho, Hachioji 192-0982, Japan
| | - Toshiyuki Nakata
- Graduate School of Engineering, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan
| | - Hao Liu
- Graduate School of Engineering, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan
| |
Collapse
|
4
|
Meng X, Liu X, Chen Z, Wu J, Chen G. Wing kinematics measurement and aerodynamics of hovering droneflies with wing damage. BIOINSPIRATION & BIOMIMETICS 2023; 18:026013. [PMID: 36745924 DOI: 10.1088/1748-3190/acb97c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Accepted: 02/06/2023] [Indexed: 06/18/2023]
Abstract
In this study, we performed successive unilateral and bilateral wing shearing to simulate wing damage in droneflies (Eristalis tenax) and measured the wing kinematics using high-speed photography technology. Two different shearing types were considered in the artificial wing damage. The aerodynamic force and power consumption were obtained by numerical method. Our major findings are the following. Different shearing methods have little influence on the kinematics, forces and energy consumption of insects. Following wing damage, among the potential strategies to adjust the three Euler angles of the wing, adjusting stroke angle (φ) in isolation, or combing the adjustment of stroke angle (φ) with pitch angle (ψ), contributed most to the change in vertical force. The balance of horizontal thrust can be restored by the adjustment of deviation angle (θ) under the condition of unilateral wing damage. Considering zero elastic energy storage, the mass-specific power (P1) increases significantly following wing damage. However, the increase in mass-specific power with 100% elastic energy storage (P2) is very small. The extra cost of the unilateral wing damage is that the energy consumption of the damaged wing and intact wing is highly asymmetrical when zero elastic energy storage is considered. The insects may alleviate the problems of increasing power consumption and asymmetric power distribution by storage and reuse of the negative inertial work of the wing.
Collapse
Affiliation(s)
- Xueguang Meng
- Shaanxi Key Laboratory of Environment and Control for Flight Vehicle, State key laboratory for Strength and Vibration of Mechanical Structures, School of Aerospace, Xi'an Jiaotong University, Xi'an 710049, People's Republic of China
| | - Xinyu Liu
- Shaanxi Key Laboratory of Environment and Control for Flight Vehicle, State key laboratory for Strength and Vibration of Mechanical Structures, School of Aerospace, Xi'an Jiaotong University, Xi'an 710049, People's Republic of China
| | - Zengshuang Chen
- Shaanxi Key Laboratory of Environment and Control for Flight Vehicle, State key laboratory for Strength and Vibration of Mechanical Structures, School of Aerospace, Xi'an Jiaotong University, Xi'an 710049, People's Republic of China
| | - Jianghao Wu
- School of Transportation Science and Engineering, Beihang University, Beijing 100191, People's Republic of China
| | - Gang Chen
- Shaanxi Key Laboratory of Environment and Control for Flight Vehicle, State key laboratory for Strength and Vibration of Mechanical Structures, School of Aerospace, Xi'an Jiaotong University, Xi'an 710049, People's Republic of China
| |
Collapse
|
5
|
Pons A, Beatus T. Distinct forms of resonant optimality within insect indirect flight motors. J R Soc Interface 2022; 19:20220080. [PMID: 35582811 DOI: 10.1098/rsif.2022.0080] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Insect flight motors are extraordinary natural structures that operate efficiently at high frequencies. Structural resonance is thought to play a role in ensuring efficient motor operation, but the details of this role are elusive. While the efficiency benefits associated with resonance may be significant, a range of counterintuitive behaviours are observed. In particular, the relationship between insect wingbeat frequencies and thoracic natural frequencies is uncertain, with insects showing wingbeat frequency modulation over both short and long time scales. Here, we offer new explanations for this modulation. We show how, in linear and nonlinear models of an indirect flight motor, resonance is not a unitary state at a single frequency, but a complex cluster of distinct and mutually exclusive states, each representing a different form of resonant optimality. Additionally, by characterizing the relationship between resonance and the state of negative work absorption within the motor, we demonstrate how near-perfect resonant energetic optimality can be maintained over significant wingbeat frequency ranges. Our analysis leads to a new conceptual model of flight motor operation: one in which insects are not energetically restricted to a precise wingbeat frequency, but instead are robust to changes in thoracic and environmental properties-an illustration of the extraordinary robustness of these natural motors.
Collapse
Affiliation(s)
- Arion Pons
- The Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Israel.,The Benin School of Computer Science and Engineering, The Hebrew University of Jerusalem, Israel
| | - Tsevi Beatus
- The Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Israel.,The Benin School of Computer Science and Engineering, The Hebrew University of Jerusalem, Israel
| |
Collapse
|
6
|
Wehmann HN, Engels T, Lehmann FO. Flight activity and age cause wing damage in house flies. J Exp Biol 2021; 225:273949. [PMID: 34904650 DOI: 10.1242/jeb.242872] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Accepted: 12/01/2021] [Indexed: 11/20/2022]
Abstract
Wing damage attenuates aerial performance in many flying animals such as birds, bats and insects. Especially insect wings are fragile and light in order to reduce inertial power requirements for flight at elevated wing flapping frequencies. There is a continuing debate on the factors causing wing damage in insects including collisions with objects, mechanical stress during flight activity, and aging. This experimental study is engaged with the reasons and significance of wing damage for flight in the house fly Musca domestica. We determined natural wing area loss under two housing conditions and recorded flight activity and flight ability throughout the animals' lifetime. Our data show that wing damage occurs on average after 6 h of flight, is sex-specific, and depends on housing conditions. Statistical tests show that both physiological age and flight activity have similar significance as predictors for wing damage. Tests on freely flying flies showed that minimum wing area for active flight is approximately 10-34% below the initial area and requires a left-right wing area asymmetry of less than approximately 25%. Our findings broadly confirm predictions from simple aerodynamic theory based on mean wing velocity and area, and are also consistent with previous wing damage measurements in other insect species.
Collapse
Affiliation(s)
| | - Thomas Engels
- Department of Animal Physiology, University of Rostock, Germany
| | | |
Collapse
|
7
|
Deora T, Sane SS, Sane SP. Wings and halteres act as coupled dual oscillators in flies. eLife 2021; 10:53824. [PMID: 34783648 PMCID: PMC8629423 DOI: 10.7554/elife.53824] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2020] [Accepted: 11/10/2021] [Indexed: 11/13/2022] Open
Abstract
The mechanics of Dipteran thorax is dictated by a network of exoskeletal linkages that, when deformed by the flight muscles, generate coordinated wing movements. In Diptera, the forewings power flight, whereas the hindwings have evolved into specialized structures called halteres, which provide rapid mechanosensory feedback for flight stabilization. Although actuated by independent muscles, wing and haltere motion is precisely phase-coordinated at high frequencies. Because wingbeat frequency is a product of wing-thorax resonance, any wear-and-tear of wings or thorax should impair flight ability. How robust is the Dipteran flight system against such perturbations? Here, we show that wings and halteres are independently driven, coupled oscillators. We systematically reduced the wing length in flies and observed how wing-haltere synchronization was affected. The wing-wing system is a strongly coupled oscillator, whereas the wing-haltere system is weakly coupled through mechanical linkages that synchronize phase and frequency. Wing-haltere link acts in a unidirectional manner; altering wingbeat frequency affects haltere frequency, but not vice versa. Exoskeletal linkages are thus key morphological features of the Dipteran thorax that ensure wing-haltere synchrony, despite severe wing damage.
Collapse
Affiliation(s)
- Tanvi Deora
- Department of Biology, University of Washington, Seattle, Washington, United States
| | | | - Sanjay P Sane
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bangalore, India
| |
Collapse
|
8
|
Ma Y, Zhao H, Ma T, Ning J, Gorb S. Wing coupling mechanism in the butterfly Pieris rapae (Lepidoptera, Pieridae) and its role in taking off. JOURNAL OF INSECT PHYSIOLOGY 2021; 131:104212. [PMID: 33662377 DOI: 10.1016/j.jinsphys.2021.104212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Revised: 02/24/2021] [Accepted: 02/24/2021] [Indexed: 06/12/2023]
Abstract
The small white cabbage butterfly (Pieris rapae) flaps its fore- and hindwings in synchrony as the wings are coupled using a wing "coupling mechanism". The coupling mechanism of butterflies includes an enlarged humeral area located at the anterior of the hindwing base and a corresponding basal posterior part of the forewing, of which the former component dorsally contacts the ventral side of the latter one. The coupling mechanism allows for the fore- and hindwings sliding in contact along the span and chord. It is of interest that butterflies still take off successfully and fly, when their wing couplings are clipped, but they are unable to properly synchronize the fore- and hindwing motions. Compared with the regular takeoff trajectory of intact butterflies that always first fly backwards and then forwards, the coupling-clipped butterflies took off in a random trajectory. Due to the clipping of the coupling mechanism, the initiation of the hindwing flapping and the abdomen rotation from upward to downward during takeoff was postponed. The coupling-clipped butterflies changed their stroke plane in upstroke to a more vertical position and strengthened the abdominal undulation. We believe our work, which for the first time investigates the influence of coupling mechanism removal on insect flight, extends our understanding on the working principle of wing coupling in insects and its significance on the flapping flight.
Collapse
Affiliation(s)
- Yun Ma
- State Key Laboratory of Explosion Science and Technology, Beijing Institute of Technology, Beijing 100081, China; Functional Morphology and Biomechanics, Zoological Institute, Kiel University, Kiel 24118, Germany
| | - Hongyan Zhao
- Beijing Institute of Astronautical System Engineering, Beijing 100076, China
| | - Tianbao Ma
- State Key Laboratory of Explosion Science and Technology, Beijing Institute of Technology, Beijing 100081, China
| | - Jianguo Ning
- State Key Laboratory of Explosion Science and Technology, Beijing Institute of Technology, Beijing 100081, China.
| | - Stanislav Gorb
- Functional Morphology and Biomechanics, Zoological Institute, Kiel University, Kiel 24118, Germany
| |
Collapse
|
9
|
Tu Z, Fei F, Liu L, Zhou Y, Deng X. Flying With Damaged Wings: The Effect on Flight Capacity and Bio-Inspired Coping Strategies of a Flapping Wing Robot. IEEE Robot Autom Lett 2021. [DOI: 10.1109/lra.2021.3059626] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
10
|
Su G, Dudley R, Pan T, Zheng M, Peng L, Li Q. Maximum aerodynamic force production by the wandering glider dragonfly ( Pantala flavescens, Libellulidae). J Exp Biol 2020; 223:jeb218552. [PMID: 32457065 DOI: 10.1242/jeb.218552] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Accepted: 05/19/2020] [Indexed: 11/20/2022]
Abstract
Maximum whole-body force production can influence behavioral outcomes for volant taxa, and may also be relevant to aerodynamic optimization in microair vehicles. Here, we describe a new method for measuring maximum force production in free-flying animals, and present associated data for the wandering glider dragonfly. Flight trajectories were repeatedly acquired from pull-up responses by insects dropped in mid-air with submaximal loads attached beneath the center of body mass. Forces were estimated from calculations of the maximum time-averaged acceleration through time, and multiple estimates were obtained per individual so as to statistically facilitate approximation of maximum capacity through use of the Weibull distribution. On a group level, wandering glider dragonflies were here estimated to be capable of producing total aerodynamic force equal to ∼4.3 times their own body weight, a value which significantly exceeds earlier estimates made for load-lifting dragonflies, and also for other volant taxa in sustained vertical load-lifting experiments. Maximum force production varied isometrically with body mass. Falling and recovery flight with submaximal load represents a new context for evaluating limits to force production by flying animals.
Collapse
Affiliation(s)
- Guanting Su
- National Key Laboratory of Science and Technology on Aero-Engine Aero-Thermodynamics, School of Energy and Power Engineering, Beihang University, Beijing 100191, China
- Department of Integrative Biology, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Robert Dudley
- Department of Integrative Biology, University of California, Berkeley, Berkeley, CA 94720, USA
- Smithsonian Tropical Research Institute, Balboa, Republic of Panama
| | - Tianyu Pan
- National Key Laboratory of Science and Technology on Aero-Engine Aero-Thermodynamics, School of Energy and Power Engineering, Beihang University, Beijing 100191, China
| | - Mengzong Zheng
- National Key Laboratory of Science and Technology on Aero-Engine Aero-Thermodynamics, School of Energy and Power Engineering, Beihang University, Beijing 100191, China
| | - Liansong Peng
- National Key Laboratory of Science and Technology on Aero-Engine Aero-Thermodynamics, School of Energy and Power Engineering, Beihang University, Beijing 100191, China
| | - Qiushi Li
- National Key Laboratory of Science and Technology on Aero-Engine Aero-Thermodynamics, School of Energy and Power Engineering, Beihang University, Beijing 100191, China
- Key Laboratory of Fluid and Power Machinery, Xihua University, Chengdu 610039, China
| |
Collapse
|
11
|
Cunningham-Minnick MJ, Peters VE, Crist TO. Bee communities and pollination services in adjacent crop fields following flower removal in an invasive forest shrub. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2020; 30:e02078. [PMID: 31971650 DOI: 10.1002/eap.2078] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Revised: 11/14/2019] [Accepted: 12/04/2019] [Indexed: 06/10/2023]
Abstract
The habitat boundaries between crops and seminatural areas influence bee movements and pollination services to crops. Edges also provide favorable conditions for invasive plants, which may usurp pollinators and reduce visitation to native or crop plants. Alternatively, floral displays of alien plants may facilitate, or increase, the pollination success of adjacent plants by attracting more pollinators to the area. Therefore, pollination services of bees from seminatural habitats to crop areas should vary with the presence of invasive floral resources and distance from habitat edges. To test the hypothesis that floral resources of invasive forest shrubs affect the bee community and pollination services in adjacent crop fields, we conducted a 2-yr field experiment along forest-crop edges at five isolated forest remnants. We removed flower buds from a dominant invasive shrub, Lonicera maackii (Amur honeysuckle), along forest-crop edges and paired removals with controls of intact flowers. The bee community, their pollination services, and flower visitation rates were quantified along a 200-m gradient into an adjacent crop field using pan traps and sentinel cucumber plants. Impacts to the bee community were dependent of bee functional traits. Larger bees visited fewer sentinel cucumber flowers in flower removal plots, which corresponded with decreased cucumber pollination compared to plots with honeysuckle flowers at distances >100 m from forest edges. Small-bodied and weaker flying bees visited sentinel plants more frequently closer to the forest edge and increased pollination services to cucumber at distances <100 m from L. maackii shrubs in flower removal plots. After 2 yr, bee abundance and species richness increased within flower removal plots across all distances. High functional diversity of the bee community increased pollination services to sentinel plants and increased cucumber production within 200 m from forest remnants. Our findings suggest that dense floral resources of invasive shrubs suppressed forest-edge bee communities and their pollination services, but also attracted large-bodied generalist bees, which were effective pollinators. This study helps explain how life histories and functional attributes of bees can predict either facilitation or suppression of pollination services to crop or native plants in response to invasive floral resources.
Collapse
Affiliation(s)
| | - Valerie E Peters
- Department of Biology, Miami University, 212 Pearson Hall, 700 East High Street, Oxford, Ohio, 45056, USA
- Department of Biological Sciences, Eastern Kentucky University, 3238 Science, 521 Lancaster Avenue, Richmond, Kentucky, 40475, USA
| | - Thomas O Crist
- Department of Biology, Miami University, 212 Pearson Hall, 700 East High Street, Oxford, Ohio, 45056, USA
| |
Collapse
|
12
|
Jankauski MA. Measuring the frequency response of the honeybee thorax. BIOINSPIRATION & BIOMIMETICS 2020; 15:046002. [PMID: 32209745 DOI: 10.1088/1748-3190/ab835b] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Insects with asynchronous flight muscles are believed to flap at the effective fundamental frequency of their thorax-wing system. Flapping in this manner leverages the natural elasticity of the thorax to reduce the energetic requirements of flight. However, to the best of our knowledge, the fundamental frequency of the insect wing-muscle-thorax system has not been measured. Here, we measure the linear frequency response function (FRF) of honeybee Apis mellifera thoraxes about their equilibrium state in order to determine their fundamental frequencies. FRFs relate the input force to output acceleration at the insect tergum and are acquired via a mechanical vibration shaker assembly. When compressed 50 μm, the thorax fundamental frequency averaged across all subjects was about 50% higher than reported wingbeat frequencies. We suspect that the measured fundamental frequencies are higher in the experiment than during flight due to boundary conditions and posthumous muscle stiffening. Next, we compress the thorax between 100-300 μm in 50 μm intervals to assess the sensitivity of the fundamental frequency to geometric modifications. For all specimens considered, the thorax fundamental frequency increased nearly monotonically with respect to level of compression. This implies that the thorax behaves as a nonlinear hardening spring when subject to large displacements, which we confirmed via static force-displacement testing. While there is little evidence that insects utilize this non-linearity during flight, the hardening characteristic may be emulated by small resonant-type flapping wing micro air vehicles to increase flapping frequency bandwidth. Overall, methods established through this work provide a foundation for further dynamical studies on insect thoraxes moving forward.
Collapse
Affiliation(s)
- Mark A Jankauski
- Mechanical and Industrial Engineering Department, Montana State University, Culbertson Hall, 100, Bozeman, MT 59717, United States of America
| |
Collapse
|
13
|
Rajabi H, Dirks JH, Gorb SN. Insect wing damage: causes, consequences and compensatory mechanisms. J Exp Biol 2020; 223:223/9/jeb215194. [DOI: 10.1242/jeb.215194] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
ABSTRACT
The evolution of wings has played a key role in the success of insect species, allowing them to diversify to fill many niches. Insect wings are complex multifunctional structures, which not only have to withstand aerodynamic forces but also need to resist excessive stresses caused by accidental collisions. This Commentary provides a summary of the literature on damage-reducing morphological adaptations in wings, covering natural causes of wing collisions, their impact on the structural integrity of wings and associated consequences for both insect flight performance and life expectancy. Data from the literature and our own observations suggest that insects have evolved strategies that (i) reduce the likelihood of wing damage and (ii) allow them to cope with damage when it occurs: damage-related fractures are minimized because wings evolved to be damage tolerant and, in the case of wing damage, insects compensate for the reduced aerodynamic efficiency with dedicated changes in flight kinematics.
Collapse
Affiliation(s)
- Hamed Rajabi
- Functional Morphology and Biomechanics, Institute of Zoology, Kiel University, Am Botanischen Garten 1-9, D-24098 Kiel, Germany
| | - Jan-Henning Dirks
- Biomimetics-Innovation-Centre, Hochschule Bremen–City University of Applied Sciences, 28199 Bremen, Germany
| | - Stanislav N. Gorb
- Functional Morphology and Biomechanics, Institute of Zoology, Kiel University, Am Botanischen Garten 1-9, D-24098 Kiel, Germany
| |
Collapse
|
14
|
Rudolf J, Wang LY, Gorb S, Rajabi H. On the fracture resistance of dragonfly wings. J Mech Behav Biomed Mater 2019; 99:127-133. [DOI: 10.1016/j.jmbbm.2019.07.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Revised: 06/21/2019] [Accepted: 07/18/2019] [Indexed: 10/26/2022]
|
15
|
Hasan J, Roy A, Chatterjee K, Yarlagadda PKDV. Mimicking Insect Wings: The Roadmap to Bioinspiration. ACS Biomater Sci Eng 2019; 5:3139-3160. [DOI: 10.1021/acsbiomaterials.9b00217] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Jafar Hasan
- Science and Engineering Faculty, Queensland University of Technology, 2 George Street, Brisbane, QLD 4001, Australia
| | - Anindo Roy
- Department of Materials Engineering, Indian Institute of Science, C. V. Raman Avenue, Bangalore 560 012, India
| | - Kaushik Chatterjee
- Department of Materials Engineering, Indian Institute of Science, C. V. Raman Avenue, Bangalore 560 012, India
| | - Prasad K. D. V. Yarlagadda
- Science and Engineering Faculty, Queensland University of Technology, 2 George Street, Brisbane, QLD 4001, Australia
| |
Collapse
|
16
|
Le Roy C, Debat V, Llaurens V. Adaptive evolution of butterfly wing shape: from morphology to behaviour. Biol Rev Camb Philos Soc 2019; 94:1261-1281. [PMID: 30793489 DOI: 10.1111/brv.12500] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Revised: 01/21/2019] [Accepted: 01/23/2019] [Indexed: 01/07/2023]
Abstract
Butterflies display extreme variation in wing shape associated with tremendous ecological diversity. Disentangling the role of neutral versus adaptive processes in wing shape diversification remains a challenge for evolutionary biologists. Ascertaining how natural selection influences wing shape evolution requires both functional studies linking morphology to flight performance, and ecological investigations linking performance in the wild with fitness. However, direct links between morphological variation and fitness have rarely been established. The functional morphology of butterfly flight has been investigated but selective forces acting on flight behaviour and associated wing shape have received less attention. Here, we attempt to estimate the ecological relevance of morpho-functional links established through biomechanical studies in order to understand the evolution of butterfly wing morphology. We survey the evidence for natural and sexual selection driving wing shape evolution in butterflies, and discuss how our functional knowledge may allow identification of the selective forces involved, at both the macro- and micro-evolutionary scales. Our review shows that although correlations between wing shape variation and ecological factors have been established at the macro-evolutionary level, the underlying selective pressures often remain unclear. We identify the need to investigate flight behaviour in relevant ecological contexts to detect variation in fitness-related traits. Identifying the selective regime then should guide experimental studies towards the relevant estimates of flight performance. Habitat, predators and sex-specific behaviours are likely to be major selective forces acting on wing shape evolution in butterflies. Some striking cases of morphological divergence driven by contrasting ecology involve both wing and body morphology, indicating that their interactions should be included in future studies investigating co-evolution between morphology and flight behaviour.
Collapse
Affiliation(s)
- Camille Le Roy
- Institut de Systématique, Evolution, Biodiversité (ISYEB), Muséum National d'Histoire Naturelle, CNRS, Sorbonne Université, EPHE, Université des Antilles, 57 rue Cuvier CP50, 75005, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité, 12 rue de l'École de Médecine, 75006, Paris, France
| | - Vincent Debat
- Institut de Systématique, Evolution, Biodiversité (ISYEB), Muséum National d'Histoire Naturelle, CNRS, Sorbonne Université, EPHE, Université des Antilles, 57 rue Cuvier CP50, 75005, Paris, France
| | - Violaine Llaurens
- Institut de Systématique, Evolution, Biodiversité (ISYEB), Muséum National d'Histoire Naturelle, CNRS, Sorbonne Université, EPHE, Université des Antilles, 57 rue Cuvier CP50, 75005, Paris, France
| |
Collapse
|
17
|
Le Roy C, Cornette R, Llaurens V, Debat V. Effects of natural wing damage on flight performance in Morpho butterflies: what can it tell us about wing shape evolution? J Exp Biol 2019; 222:jeb.204057. [DOI: 10.1242/jeb.204057] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Accepted: 07/30/2019] [Indexed: 01/09/2023]
Abstract
Flying insects frequently experience wing damage during their life. Such irreversible alterations of wing shape affect flight performance and ultimately fitness. Insects have been shown to compensate for wing damage through various behavioural adjustments, but the importance of damage location over the wings has been scarcely studied. Using natural variation in wing damage, here we tested how the loss of different wing parts affect flight performance. We quantified flight performance in two species of large butterflies, Morpho helenor and M. achilles, caught in the wild, and displaying large variation in the extent and location of wing damage. We artificially generated more severe wing damage in our sample to contrast natural vs. higher magnitude of wing loss. Wing shape alteration across our sample was quantified using geometric morphometrics to test the effect of different damage distributions on flight performance. Our results show that impaired flight performance clearly depends on damage location over the wings, pointing out a relative importance of different wing parts for flight. Deteriorated forewings leading edge most crucially affected flight performance, specifically decreasing flight speed and proportion of gliding flight. In contrast, most frequent natural damage such as scattered wing margin had no detectable effect on flight behaviour. Damages located on the hindwings – although having a limited effect on flight – were associated with reduced flight height, suggesting that fore- and hindwings play different roles in butterfly flight. By contrasting harmless and deleterious consequences of various types of wing damage, our study points at different selective regimes acting on morphological variations of butterfly wings.
Collapse
Affiliation(s)
- Camille Le Roy
- Institut de Systématique, Evolution, Biodiversité (ISYEB), Muséum National d'Histoire Naturelle, CNRS, Sorbonne Université, EPHE, Université des Antilles, CP50, 75005, Paris, France
- Université Paris Descartes, Sorbonne Paris Cité, 12 rue de l’École de Médecine, 75006, Paris, France
| | - Raphaël Cornette
- Institut de Systématique, Evolution, Biodiversité (ISYEB), Muséum National d'Histoire Naturelle, CNRS, Sorbonne Université, EPHE, Université des Antilles, CP50, 75005, Paris, France
| | - Violaine Llaurens
- Institut de Systématique, Evolution, Biodiversité (ISYEB), Muséum National d'Histoire Naturelle, CNRS, Sorbonne Université, EPHE, Université des Antilles, CP50, 75005, Paris, France
| | - Vincent Debat
- Institut de Systématique, Evolution, Biodiversité (ISYEB), Muséum National d'Histoire Naturelle, CNRS, Sorbonne Université, EPHE, Université des Antilles, CP50, 75005, Paris, France
| |
Collapse
|
18
|
Margotta JW, Roberts SP, Elekonich MM. Effects of flight activity and age on oxidative damage in the honey bee, Apis mellifera. ACTA ACUST UNITED AC 2018; 221:jeb.183228. [PMID: 29724776 DOI: 10.1242/jeb.183228] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Accepted: 04/26/2018] [Indexed: 02/06/2023]
Abstract
Frequent and highly aerobic behaviors likely contribute to naturally occurring stress, accelerate senescence and limit lifespan. To understand how the physiological and cellular mechanisms that determine the onset and duration of senescence are shaped by behavioral development and behavioral duration, we exploited the tractability of the honey bee (Apis mellifera) model system. First, we determined whether a cause-effect relationship exists between honey bee flight and oxidative stress by comparing oxidative damage accrued from intense flight bouts to damage accrued from d-galactose ingestion, which induces oxidative stress and limits lifespan in other insects. Second, we experimentally manipulated the duration of honey bee flight across a range of ages to determine the effects on reactive oxygen species (ROS) accumulation and associated enzymatic antioxidant protective mechanisms. In bees fed d-galactose, lipid peroxidation (assessed by measuring malondialdehyde levels) was higher than in bees fed sucrose and age-matched bees with a high and low number of flight experiences collected from a colony. Bees with high amounts of flight experience exhibited elevated 8-hydroxy-2'-deoxyguanosine, a marker of oxidative DNA damage, relative to bees with less flight experience. Bees with high amounts of flight experience also showed increased levels of pro-oxidants (superoxide and hydrogen peroxide) and decreased or unchanged levels of antioxidants (superoxide dismutase and catalase). These data implicate an imbalance of pro- to anti-oxidants in flight-associated oxidative stress, and reveal how behavior can damage a cell and consequently limit lifespan.
Collapse
Affiliation(s)
- Joseph W Margotta
- University of Nevada, Las Vegas, School of Life Sciences, Biology Department, Las Vegas, NV 89141, USA
| | | | - Michelle M Elekonich
- University of Nevada, Las Vegas, School of Life Sciences, Biology Department, Las Vegas, NV 89141, USA.,National Science Foundation, Arlington, VA 22230, USA
| |
Collapse
|
19
|
Mountcastle AM, Alexander TM, Switzer CM, Combes SA. Wing wear reduces bumblebee flight performance in a dynamic obstacle course. Biol Lett 2017; 12:rsbl.2016.0294. [PMID: 27303054 DOI: 10.1098/rsbl.2016.0294] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2016] [Accepted: 05/18/2016] [Indexed: 11/12/2022] Open
Abstract
Previous work has shown that wing wear increases mortality in bumblebees. Although a proximate mechanism for this phenomenon has remained elusive, a leading hypothesis is that wing wear increases predation risk by reducing flight manoeuvrability. We tested the effects of simulated wing wear on flight manoeuvrability in Bombus impatiens bumblebees using a dynamic obstacle course designed to push bees towards their performance limits. We found that removing 22% wing area from the tips of both forewings (symmetric wear) caused a 9% reduction in peak acceleration during manoeuvring flight, while performing the same manipulation on only one wing (asymmetric wear) did not significantly reduce maximum acceleration. The rate at which bees collided with obstacles was correlated with body length across all treatments, but wing wear did not increase collision rate, possibly because shorter wingspans allow more room for bees to manoeuvre. This study presents a novel method for exploring extreme flight manoeuvres in flying insects, eliciting peak accelerations that exceed those measured during flight through a stationary obstacle course. If escape from aerial predation is constrained by acceleration capacity, then our results offer a potential explanation for the observed increase in bumblebee mortality with wing wear.
Collapse
Affiliation(s)
- Andrew M Mountcastle
- School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138, USA
| | - Teressa M Alexander
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA
| | - Callin M Switzer
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA
| | - Stacey A Combes
- Department of Neurobiology, Physiology, and Behavior, University of California Davis, Davis, CA 95616, USA
| |
Collapse
|
20
|
Fernández MJ, Driver ME, Hedrick TL. Asymmetry costs: effects of wing damage on hovering flight performance in the hawkmoth Manduca sexta. ACTA ACUST UNITED AC 2017; 220:3649-3656. [PMID: 28794226 DOI: 10.1242/jeb.153494] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Accepted: 08/04/2017] [Indexed: 11/20/2022]
Abstract
Flight performance is fundamental to the fitness of flying organisms. Whilst airborne, flying organisms face unavoidable wing wear and wing area loss. Many studies have tried to quantify the consequences of wing area loss to flight performance with varied results, suggesting that not all types of damage are equal and different species may have different means to compensate for some forms of wing damage with little to no cost. Here, we investigated the cost of control during hovering flight with damaged wings, specifically wings with asymmetric and symmetric reductions in area, by measuring maximum load lifting capacity and the metabolic power of hovering flight in hawkmoths (Manduca sexta). We found that while asymmetric and symmetric reductions are both costly in terms of maximum load lifting and hovering efficiency, asymmetric reductions are approximately twice as costly in terms of wing area lost. The moths also did not modulate flapping frequency and amplitude as predicted by a hovering flight model, suggesting that the ability to do so, possibly tied to asynchronous versus synchronous flight muscles, underlies the varied responses found in different wing clipping experiments.
Collapse
Affiliation(s)
| | - Marion E Driver
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Tyson L Hedrick
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599, USA
| |
Collapse
|
21
|
Bomphrey RJ, Nakata T, Phillips N, Walker SM. Smart wing rotation and trailing-edge vortices enable high frequency mosquito flight. Nature 2017; 544:92-95. [PMID: 28355184 PMCID: PMC5412966 DOI: 10.1038/nature21727] [Citation(s) in RCA: 96] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Accepted: 02/27/2017] [Indexed: 02/06/2023]
Abstract
Mosquitoes exhibit unusual wing kinematics; their long, slender wings flap at remarkably high frequencies for their size (>800 Hz)and with lower stroke amplitudes than any other insect group. This shifts weight support away from the translation-dominated, aerodynamic mechanisms used by most insects, as well as by helicopters and aeroplanes, towards poorly understood rotational mechanisms that occur when pitching at the end of each half-stroke. Here we report free-flight mosquito wing kinematics, solve the full Navier-Stokes equations using computational fluid dynamics with overset grids, and validate our results with in vivo flow measurements. We show that, although mosquitoes use familiar separated flow patterns, much of the aerodynamic force that supports their weight is generated in a manner unlike any previously described for a flying animal. There are three key features: leading-edge vortices (a well-known mechanism that appears to be almost ubiquitous in insect flight), trailing-edge vortices caused by a form of wake capture at stroke reversal, and rotational drag. The two new elements are largely independent of the wing velocity, instead relying on rapid changes in the pitch angle (wing rotation) at the end of each half-stroke, and they are therefore relatively immune to the shallow flapping amplitude. Moreover, these mechanisms are particularly well suited to high aspect ratio mosquito wings.
Collapse
Affiliation(s)
- Richard J Bomphrey
- Structure and Motion Laboratory, Royal Veterinary College, University of London, Hatfield AL9 7TA, UK
| | - Toshiyuki Nakata
- Structure and Motion Laboratory, Royal Veterinary College, University of London, Hatfield AL9 7TA, UK.,Graduate School of Engineering, Chiba University, 1-33, Yayoi-cho, Inage-ku, Chiba-shi, Chiba 263-8522 Japan
| | - Nathan Phillips
- Structure and Motion Laboratory, Royal Veterinary College, University of London, Hatfield AL9 7TA, UK
| | - Simon M Walker
- Department of Zoology, University of Oxford, Oxford OX1 3PS, UK
| |
Collapse
|
22
|
de Verges J, Nehring V. A critical look at proximate causes of social insect senescence: damage accumulation or hyperfunction? CURRENT OPINION IN INSECT SCIENCE 2016; 16:69-75. [PMID: 27720053 DOI: 10.1016/j.cois.2016.05.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2016] [Revised: 04/26/2016] [Accepted: 05/02/2016] [Indexed: 06/06/2023]
Abstract
Social insects have received attention for their extreme lifespan variation and reversal of the fecundity/longevity trade-off. However, proximate causes of senescence in general are disputed, and social insects often fail to meet the predictions of prevailing models. We present evidence for and against the long-held free radical theory of aging in social insects, and consider the application of the competing hyperfunction theory. Current results present problems for both theories, and a more complex picture of the biological processes involved emerges. The eusocial life style might allow colonies to allocate damage in ways that create seemingly senescence-free life histories. Only experimental approaches characterizing multiple senescence factors simultaneously will shed light on how social insects defy the conventions of senescence.
Collapse
Affiliation(s)
- Jane de Verges
- University of Freiburg, Biology I, Evolution & Ecology, Hauptstraße 1, D-79104 Freiburg, Germany
| | - Volker Nehring
- University of Freiburg, Biology I, Evolution & Ecology, Hauptstraße 1, D-79104 Freiburg, Germany.
| |
Collapse
|
23
|
Kassner Z, Dafni E, Ribak G. Kinematic compensation for wing loss in flying damselflies. JOURNAL OF INSECT PHYSIOLOGY 2016; 85:1-9. [PMID: 26598807 DOI: 10.1016/j.jinsphys.2015.11.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2015] [Revised: 11/13/2015] [Accepted: 11/17/2015] [Indexed: 05/28/2023]
Abstract
Flying insects can tolerate substantial wing wear before their ability to fly is entirely compromised. In order to keep flying with damaged wings, the entire flight apparatus needs to adjust its action to compensate for the reduced aerodynamic force and to balance the asymmetries in area and shape of the damaged wings. While several studies have shown that damaged wings change their flapping kinematics in response to partial loss of wing area, it is unclear how, in insects with four separate wings, the remaining three wings compensate for the loss of a fourth wing. We used high-speed video of flying blue-tailed damselflies (Ischnura elegans) to identify the wingbeat kinematics of the two wing pairs and compared it to the flapping kinematics after one of the hindwings was artificially removed. The insects remained capable of flying and precise maneuvering using only three wings. To compensate for the reduction in lift, they increased flapping frequency by 18±15.4% on average. To achieve steady straight flight, the remaining intact hindwing reduced its flapping amplitude while the forewings changed their stroke plane angle so that the forewing of the manipulated side flapped at a shallower stroke plane angle. In addition, the angular position of the stroke reversal points became asymmetrical. When the wingbeat amplitude and frequency of the three wings were used as input in a simple aerodynamic model, the estimation of total aerodynamic force was not significantly different (paired t-test, p=0.73) from the force produced by the four wings during normal flight. Thus, the removal of one wing resulted in adjustments of the motions of the remaining three wings, exemplifying the precision and plasticity of coordination between the operational wings. Such coordination is vital for precise maneuvering during normal flight but it also provides the means to maintain flight when some of the wings are severely damaged.
Collapse
Affiliation(s)
- Ziv Kassner
- Department of Zoology, Faculty of Life Sciences, Tel Aviv University, 6997801, Israel
| | - Eyal Dafni
- Department of Zoology, Faculty of Life Sciences, Tel Aviv University, 6997801, Israel
| | - Gal Ribak
- Department of Zoology, Faculty of Life Sciences, Tel Aviv University, 6997801, Israel; Sagol School of Neuroscience, Tel Aviv University, 6997801, Israel.
| |
Collapse
|
24
|
Southey BR, Zhu P, Carr-Markell MK, Liang ZS, Zayed A, Li R, Robinson GE, Rodriguez-Zas SL. Characterization of Genomic Variants Associated with Scout and Recruit Behavioral Castes in Honey Bees Using Whole-Genome Sequencing. PLoS One 2016; 11:e0146430. [PMID: 26784945 PMCID: PMC4718678 DOI: 10.1371/journal.pone.0146430] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Accepted: 12/15/2015] [Indexed: 12/01/2022] Open
Abstract
Among forager honey bees, scouts seek new resources and return to the colony, enlisting recruits to collect these resources. Differentially expressed genes between these behaviors and genetic variability in scouting phenotypes have been reported. Whole-genome sequencing of 44 Apis mellifera scouts and recruits was undertaken to detect variants and further understand the genetic architecture underlying the behavioral differences between scouts and recruits. The median coverage depth in recruits and scouts was 10.01 and 10.7 X, respectively. Representation of bacterial species among the unmapped reads reflected a more diverse microbiome in scouts than recruits. Overall, 1,412,705 polymorphic positions were analyzed for associations with scouting behavior, and 212 significant (p-value < 0.0001) associations with scouting corresponding to 137 positions were detected. Most frequent putative transcription factor binding sites proximal to significant variants included Broad-complex 4, Broad-complex 1, Hunchback, and CF2-II. Three variants associated with scouting were located within coding regions of ncRNAs including one codon change (LOC102653644) and 2 frameshift indels (LOC102654879 and LOC102655256). Significant variants were also identified on the 5’UTR of membrin, and 3’UTRs of laccase 2 and diacylglycerol kinase theta. The 60 significant variants located within introns corresponded to 39 genes and most of these positions were > 1000 bp apart from each other. A number of these variants were mapped to ncRNA LOC100578102, solute carrier family 12 member 6-like gene, and LOC100576965 (meprin and TRAF-C homology domain containing gene). Functional categories represented among the genes corresponding to significant variants included: neuronal function, exoskeleton, immune response, salivary gland development, and enzymatic food processing. These categories offer a glimpse into the molecular support to the behaviors of scouts and recruits. The level of association between genomic variants and scouting behavior observed in this study may be linked to the honey bee’s genomic plasticity and fluidity of transition between castes.
Collapse
Affiliation(s)
- Bruce R. Southey
- Department of Animal Sciences, University of Illinois Urbana-Champaign, Urbana, Illinois, United States of America
| | - Ping Zhu
- Biodynamic Optical Imaging Center, College of Life Sciences, and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, China
| | - Morgan K. Carr-Markell
- School of Integrative Biology, Ecology, Evolution, and Conservation Biology Program, University of Illinois Urbana-Champaign, Urbana, Illinois, United States of America
| | - Zhengzheng S. Liang
- School of Molecular and Cell Biology and Neuroscience Program, University of Illinois Urbana-Champaign, Urbana, Illinois, United States of America
| | - Amro Zayed
- Department of Biology, York University, Toronto, Ontario, Canada
| | - Ruiqiang Li
- Novogene Bioinformatics Institute, Beijing, China and Biodynamic Optical Imaging Center, Peking-Tsinghua Center for Life Sciences and School of Life Sciences, Peking University, Beijing, China
| | - Gene E. Robinson
- Carle Woese Institute for Genomic Biology, Department of Entomology, and Neuroscience Program, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
| | - Sandra L. Rodriguez-Zas
- Department of Animal Sciences, Department of Statistics, Neuroscience Program, and Carle Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
- * E-mail:
| |
Collapse
|
25
|
Roberts JC, Cartar RV. Shape of wing wear fails to affect load lifting in common eastern bumble bees (Bombus impatiens) with experimental wing wear. CAN J ZOOL 2015. [DOI: 10.1139/cjz-2014-0317] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Wing wear reflects the accumulation of irreversible damage to an insect’s wings over its lifetime and this damage should influence flight performance. In the case of bumble bees, flight seems robust to variation in wing-area asymmetry and air pressure, but not to loss of wing area. However, how the pattern of wing wear affects flight performance remains unstudied. In nature, wing wear typically occurs in a ragged and haphazard pattern along the wing’s trailing margin, a shape strikingly different from the straight cut applied in past studies. In this study, we test if shape of wing wear (implemented as four distinct treatments plus a control) affects maximum load-lifting capabilities and wingbeat frequency of worker common eastern bumble bees (Bombus impatiens Cresson, 1863). We found that shape of wing wear of 171 mg bees had no detectable effect on maximum load-lifting capability (detectable effect size = 18 mg) or on wingbeat frequency (detectable effect size = 15 Hz), but that loss of wing area reduced load-lifting capability and increased wingbeat frequency. The importance of wing area in explaining the load-lifting ability of bumble bees is reinforced in this study. But, paradoxically, shape of wing wear did not detectably affect lift generation, which is determined by unsteady aerodynamic forces in these lift-reliant insects.
Collapse
Affiliation(s)
- Jordan C. Roberts
- Department of Biological Sciences, University of Calgary, 2500 University Drive Northwest, Calgary, AB T2N 1N4, Canada
- Department of Biological Sciences, University of Calgary, 2500 University Drive Northwest, Calgary, AB T2N 1N4, Canada
| | - Ralph V. Cartar
- Department of Biological Sciences, University of Calgary, 2500 University Drive Northwest, Calgary, AB T2N 1N4, Canada
- Department of Biological Sciences, University of Calgary, 2500 University Drive Northwest, Calgary, AB T2N 1N4, Canada
| |
Collapse
|