Thermal physiological ecology of Colias butterflies in flight

Summary As a comparison to the many studies of larger flying insects, we carried out an initial study of heat balance and thermal dependence of flight of a small butterfly (Colias) in a wind tunnel and in the wild.Unlike many larger, or facultatively endothermic insects, Colias do not regulate heat loss by altering hemolymph circulation between thorax and abdomen as a function of body temperature. During flight, thermal excess of the abdomen above ambient temperature is weakly but consistently coupled to that of the thorax. Total heat loss is best expressed as the sum of heat loss from the head and thorex combined plus heat loss from the abdomen because the whole body is not isothermal. Convective cooling is a simple linear function of the square root of air speed from 0.2 to 2.0 m/s in the wind tunnel. Solar heat flux is the main source of heat gain in flight, just as it is the exclusive source for warmup at rest. The balance of heat gain from sunlight versus heat loss from convection and radiation does not appear to change by more than a few percent between the wings-closed basking posture and the variable opening of wings in flight, although several aspects require further study. Heat generation by action of the flight muscles is small (on the order of 100 m W/g tissue) compared to values reported for other strongly flying insects. Colias appears to have only very limited capacity to modulate flight performance. Wing beat frequency varies from 12–19 Hz depending on body mass, air speed, and thoracic temperature. At suboptimal flight temperatures, wing beat frequency increases significantly with thoracic temperature and body mass but is independent of air speed. Within the reported thermal optimum of 35–39°C, wing beat frequency is negatively dependent on air speed at values above 1.5 m/s, but independent of mass and body temperature. Flight preference of butterflies in the wind tunnel is for air speeds of 0.5–1.5 m/s, and no flight occurs at or above 2.5 m/s. Voluntary flight initiation in the wild occurs only at air speeds 1.4 m/s.In the field, Colias fly just above the vegetation at body temperatures of 1–2°C greater than when basking at the top of the vegetation. These measurements are consistent with our findings on low heat gain from muscular activity during flight. Basking temperatures of butterflies sheltered from the wind within the vegetation were 1–2°C greater than flight temperatures at vegetation height.     

Flight Characteristics of Two Plume Moths, Alucita pentadacty/a L. and Orneodes hexadactyla L. (Microlepidoptera)

Norberg, R. Å. (Department of Zoology, University of Gothenburg, Göteborg, Sweden.) Flight characteristics of two plume moths, Alucita pentadactyla L. and Orneodes hexadactyla L. (Microlepidoptera). Zool. Scripta 1 (6): 241–246,1972.–Multiple exposure photographs of up to 100 exposures/sec were taken on two plume moth species in free, unrestrained flight, in order to determine approximate lift/drag ratios and other functional characteristics of their wings, which are of a remarkable structure for insects of this size. In Alucita the forewing is cleft in two fringed lobes, the hind-wing in three, while in Orneodes both forewing and hindwing are deeply cleft in six very narrow, fringed lobes. Wing stroke frequencies are ca. 33 Hz in A. pentadactyla and ca. 40 Hz in O. hexadactyla. During both the downstroke and the upstroke the fringed wing lobes lie edge against edge, thus forming a continuous wing surface. The upstroke seems to contribute no useful forces in A. pentadactyla, possibly some propulsive force in O. hexadactyla. The wings are strongly supinated in the upstroke to minimize drag. From relative wind diagrams, lift/drag ratios of 1.1 and 1.4 (minimum values) can be read for A. pentadactyla and O. hexadactyla, respectively. It is thus clear that these species do not make more use of drag forces than of lift forces. However, in A. pentadactyla the drag force in the downstroke may be almost as large as the lift force. Since drag certainly is small in the upstroke, the drag force probably contributes significantly to useful forces for flight in A. pentadactyla. These plume moths operate at Reynolds numbers of ca. 700. Reynolds numbers are calculated for very small insects. It is obvious that the wings of the smallest insects must be operating at Reynolds numbers of about 1. The fringed wings of small insects are briefly discussed.     

Visual ground pattern modulates flight speed of male Oriental fruit moth Grapholita molesta

Insects flying in a horizontal pheromone plume must attend to visual cues to ensure that they make upwind progress. Moreover, it is suggested that flying insects will also modulate their flight speed to maintain a constant retinal angular velocity of terrestrial contrast elements. Evidence from flies and honeybees supports such a hypothesis, although tests with male moths and beetles flying in pheromone plumes are not conclusive. These insects typically fly faster at higher elevations above a high‐contrast ground pattern, as predicted by the hypothesis, although the increase in speed is not sufficient to demonstrate quantitatively that they maintain constant visual angular velocity of the ground pattern. To test this hypothesis more rigorously, the flight speed of male oriental fruit moths (OFM) Grapholita molesta Busck (Lepidoptera: Tortricidae) flying in a sex pheromone plume in a laboratory wind tunnel is measured at various heights (5–40 cm) above patterns of different spatial wavelength (1.8–90°) in the direction of flight. The OFM modulate their flight speed three‐fold over different patterns. They fly fastest when there is no pattern in the tunnel or the contrast elements are too narrow to resolve. When the spatial wavelength of the pattern is sufficiently wide to resolve, moths fly at a speed that tends to maintain a visual contrast frequency of 3.5 ± 3.2 Hz rather than a constant angular velocity, which varies from 57 to 611° s^?1. In addition, for the first time, it is also demonstrated that the width of a contrast pattern perpendicular to the flight direction modulates flight speed.     

Surface-skimming stoneflies and mayflies: the taxonomic and mechanical diversity of two-dimensional aerodynamic locomotion

The best supported hypothesis for the evolutionary origin of insect wings is that they evolved from articulated, leg-derived respiratory structures of aquatic ancestors. However, there are no fossils of the immediate ancestors of winged insects, and it is difficult to imagine how a functional transition from gills to wings could have occurred. Recent studies of surface-skimming locomotion in stoneflies and mayflies offer a plausible solution by showing how rudimentary wings and muscle power can be used to accomplish two-dimensional aerodynamic locomotion on the surface of water. Here we extend that line of research by examining the phylogenetic distribution and mechanistic diversity of surface skimming in stoneflies, along with a limited examination of mayflies. These investigations reveal both a broad taxonomic occurrence and a fine gradation of mechanically distinct forms. Distinct forms of wing-flapping surface skimming include (1) stoneflies that flap their wings weakly while maintaining their body in contact with the water and undulating their abdomen laterally in a swimming-like motion, (2) stoneflies that skim while elevating their body above the water and maintaining all six legs on the surface, (3) stoneflies and mayflies that skim with only four legs on the water surface, (4) stoneflies that skim with only their two hind legs on the surface, and (5) stoneflies that, beginning with a series of leg motions nearly identical to hind-leg skimmers, use their hind legs to jump from the water into the air to initiate flapping flight. Comparisons across these forms of skimming show that wing-beat amplitude, horizontal velocity, and the verticality of aerodynamic force production increase as the body orientation becomes more upright and contact with the water is minimized. These behaviors illustrate a mechanical pathway by which flying insects could have evolved from swimming ancestors via a series of finely graded intermediate stages. The phylogenetic distribution of skimming and flight in stoneflies does not indicate any clear directionality toward either greater or lesser aerodynamic abilities; however, the broad and apparently basal phylogenetic distribution of skimming taxa supports the hypothesis that the common ancestor of stoneflies was a surface skimmer. This may also be true for the common ancestor of stoneflies and mayflies, that is, the first winged insects. We combine these data with fossil evidence to form a synthetic model for the evolution of flying insects from surface skimmers.     

Biomechanics and biomimetics in insect-inspired flight systems

Insect- and bird-size drones—micro air vehicles (MAV) that can perform autonomous flight in natural and man-made environments are now an active and well-integrated research area. MAVs normally operate at a low speed in a Reynolds number regime of 10⁴–10⁵ or lower, in which most flying animals of insects, birds and bats fly, and encounter unconventional challenges in generating sufficient aerodynamic forces to stay airborne and in controlling flight autonomy to achieve complex manoeuvres. Flying insects that power and control flight by flapping wings are capable of sophisticated aerodynamic force production and precise, agile manoeuvring, through an integrated system consisting of wings to generate aerodynamic force, muscles to move the wings and a control system to modulate power output from the muscles. In this article, we give a selective review on the state of the art of biomechanics in bioinspired flight systems in terms of flapping and flexible wing aerodynamics, flight dynamics and stability, passive and active mechanisms in stabilization and control, as well as flapping flight in unsteady environments. We further highlight recent advances in biomimetics of flapping-wing MAVs with a specific focus on insect-inspired wing design and fabrication, as well as sensing systems.This article is part of the themed issue ‘Moving in a moving medium: new perspectives on flight’.     

A 'polarisation sun-dial' dictates the optimal time of day for dispersal by flying aquatic insects

1. Daily changes in the flight activity of aquatic insects have been investigated in only a few water beetles and bugs. The diel flight periodicity of aquatic insects and the environmental factors governing it are poorly understood. 2. We found that primary aquatic insects belonging to 99 taxa (78 Coleoptera, 21 Heteroptera) fly predominantly in mid‐morning, and/or around noon and/or at nightfall. There appears to be at least four different types of diurnal flight activity rhythm in aquatic insects, characterised by peak(s): (i) in mid‐morning; (ii) in the evening; (iii) both in mid‐morning and the evening; (iv) around noon and again in the evening. These activity maxima are quite general and cannot be explained exclusively by daily fluctuations of air temperature, humidity, wind speed and risks of predation, which are all somewhat stochastic. 3. We found experimental evidence that the proportion (%) P(θ) of reflecting surfaces detectable polarotactically as ‘water’ is always maximal at the lowest (dawn and dusk) and highest (noon) angles of solar elevation (θ) for dark reflectors while P(θ) is maximal at dawn and dusk (low solar elevations) for bright reflectors under clear or partly cloudy skies. 4. From the temporal coincidence between peaks in the diel flight activity of primary aquatic insects and the polarotactic detectability P(θ) of water surfaces we conclude that the optimal times of day for aquatic insects to disperse are the periods of low and high solar elevations θ. The θ‐dependent reflection–polarisation patterns, combined with an appropriate air temperature, clearly explain why polarotactic aquatic insects disperse to new habitats in mid‐morning, and/or around noon and/or at dusk. We call this phenomenon the ‘polarisation sun‐dial’ of dispersing aquatic insects.     

The effect of air velocity on the wingstroke frequency of the blowflyCalliphora erythrocephala

Summary The effect of air velocity and pressure on the wingstroke frequency ofCalliphora erythrocephala, flying in a windtunnel, was studied. The results can be understood by considering the flight mechanism as a mechanical oscillator with an inertia, that depends on air velocity and pressure, without any need for nervous control.The effect of changes in air velocity on the wingstroke frequency was calculated, taking the inertia of a steady two-dimensional boundary layer around the wings as the variable part of the inertia of the flight mechanism. The calculated effect was ten times smaller than that observed experimentally. The reason for this discrepancy is discussed.     

The adaptive significance of alpine melanism in the butterfly Parnassius phoebus F. (Lepidoptera: Papilionidae)

Summary The adaptive significance of alpine melanism, the tendancy for insects to become darker with increased elevation and latitude, was investigated using the butterfly Parnassius phoebus. The effects on temperature dependent activity of five components of overall wing melanism, as well as size, were examined. The components of wing melanism examined were the transparency of the basal hindwing and distal fore-wing areas, the width of the black patch in the basal hind-wing area and the proportion of black to white scales in that area, and the proportion of the distal fore-wing covered by predominantly black scaling.The body temperature of dead specimens was correlated with air temperature, solar radiation, the width of the black patch at the base of the wings, and the proportion of black to white scales at the base of the wings. The minimum air temperatures and solar radiation levels required for initiation of flight did not vary with wing melanism of P. phoebus, in contrast to the results found for Colias butterflies by Roland (1982). However, under environmental conditions suitable for flight initiation, males with a higher proportion of black to white scales in the basal area of the hind-wing, and wider basal black patches, spent a greater proportion of time in flight at low air temperatures and low insolation. Increased basal wing melanism was also associated with increased movement of males within a population. In contrast, melanism in the distal area of the wings has no effect on activities which are dependant on body temperature. The amount of time spent feeding did not vary with differences in wing melanism. I suggest that in dorsal basking, slow-flying butterflies (Parnassius) basal wing color affects body temperature primarily during flight (rather than while basking), such that butterflies with darker wing bases cool down less rapidly because they absorb more solar radiation during flight.     

AERODYNAMICS,THERMOREGULATION, AND THE EVOLUTION OF INSECT WINGS: DIFFERENTIAL SCALING AND EVOLUTIONARY CHANGE

We examine several aerodynamic and thermoregulatory hypotheses about possible adaptive factors in the evolution of wings from small winglets in insects. Using physical models of Paleozoic insects in a wind tunnel, we explore the potential effects of wings for increasing gliding distance, increasing dispersal distance during parachuting, improving attitude control or stability, and elevating body temperatures during thermoregulation. The effects of body size and shape, wing length, number, and venation, and meteorological conditions are considered. Hypotheses consistent with both fixed and moveable wing articulations are examined. Short wings have no significant effects on any of the aerodynamic characteristics, relative to wingless models, while large wings do have significant effects. In contrast, short wings have large thermoregulatory effects relative to wingless models, but further increases in wing length do not significantly affect thermoregulatory performance. At any body size, there is a wing length below which there are significant thermoregulatory effects of increasing wing length, and above which there are significant aerodynamic effects of increasing wing length. The relative wing length at which this transition occurs decreases with increasing body size. These results suggest that there could be no effective selection for increasing wing length in wingless or short-winged insects in relation to increased aerodynamic capacity. Our results are consistent with the hypothesis that insect wings initially served a thermoregulatory function and were used for aerodynamic functions only at larger wing lengths and/or body sizes. Thus, we propose that thermoregulation was the primary adaptive factor in the early evolution of wings that preadapted them for the subsequent evolution of flight. Our results illustrate an evolutionary mechanism in which a purely isometric change in body size may produce a qualitative change in the function of a given structure. We propose a hypothesis in which the transition from thermoregulatory to aerodynamic function for wings involved only isometric changes in body size and argue that changes in body form were not a prerequisite for this major evolutionary change in function.     

Behavioral thermoregulation inpalmipenna aeoleoptera (neuroptera): Do the hypertrophied hindwings play a role?

The hypertrophied hindwings of Palmipenna aeoleoptera (Neuroptera) were examined for a possible thermoregulatory role. These wings arise from basal stalks which expand into large, flattened, darkly pigmented, and vascularized dilations. During the cooler times of the day the insects basked by crouching with the body and hindwings held horizontally in contact with rocks. As air temperatures increased, insects stilted with the hindwings held at 90° to the horizontal. Thoracic temperatures of these ectotherms correlated with air temperatures (T_thorax = 1.55T_air –10.99), with maximum recorded thoracic temperatures of 47°C. No differences were found between thoracic temperatures of males and those of females, although males had far larger hindwings. Live insects caught on rocks were consistently cooler than dead insects (operational temperature thermometers) on rocks. This may be attributed to convective cooling in flight just prior to capture, and stilting, behavior patterns that were frequent during the hottest times of the day. Thoracic temperatures of insects resting on rocks were frequently higher than operational temperature thermometers in air, suggesting that warming resulted from basking on rocks. The minimum body temperature for flight was 27°C. In the laboratory, hindwing ablation altered neither the rate (using time constants) of heating or cooling nor the equilibrium temperature of the body, showing that the hindwings play no direct role in heat uptake or loss.     

To what extent can the tiny parasitoid wasps,Eretmocerus mundus,fly upwind?

Body miniaturization in insects is predicted to result in decreased flight speed and therefore limited ability of these insects to fly upwind. Therefore, tiny insects are often regarded as relying on passive dispersal by winds. We tested this assumption in a wind tunnel by measuring the burst speed of Eretmocerus mundus (Mercet), a beneficial parasitoid wasp with body length <1 mm. Insects were filmed flying upwind towards a UV light source in a range of wind speed 0–0.5 m/s. The Insects flew towards the UV light in the absence and presence of wind but increased their flight speed in the presence of wind. They also changed flight direction to be directly upwind and maintained this body orientation even while drifted backwards relative to the ground by stronger winds. Field measurements showed that the average flight speed observed in the wind tunnel (0.3 m/s) is sufficient to allow flying between plants even when the wind speed above the vegetation was 3–5 folds higher. A simulation of the ability of the insects to control their flight trajectory towards a visual target (sticky traps) in winds show that the insects can manipulate their progress relative to the ground even when the wind speed exceeds their flight speed. The main factors determining the ability of the insects to reach the trap were trap diameter and the difference between insect flight speed and wind speed. The simulation also predicts the direction of arrival to the sticky target showing that many of the insects reach the target from the leeward side (i.e. by flight upwind). In light of these results, the notion that miniature insects passively disperse by winds is misleading because it disregards the ability of the insects to control their drift relative to the ground in winds that are faster than their flight speed.     

Rowing locomotion by a stonefly that possesses the ancestral pterygote condition of co-occurring wings and abdominal gills

A leading hypothesis for the origin of insect wings is that they evolved from thoracic gills that were serial homologues of the abdominal gills present in fossil pterygotes and in the nymphs of some modern mayflies, damselflies and stoneflies. Co-occurrence of thoracic wings and abdominal gills is the primitive condition for fossil pterygote insects, whereas the winged stage of modern insects almost exclusively lacks abdominal gills. Here we examine the locomotor behaviour and gill morphology of a stonefly, Diamphipnopsis samali (Plecoptera), which retains abdominal gills in the winged adult stage. This species can fly, but also uses its forewings as oars to accomplish rowing locomotion along the surface of water. The abdominal gills are in contact with both air and water during rowing, and their elaborately folded surface suggests an ability to contribute to gas-exchange. D. samali nymphs also have behaviours that place them in locations where their gills are exposed to air; they forage at night at the stream margin and within bubble curtains in rapids. These traits may exemplify an early pterygote condition in which gill and protowing function overlapped in an amphibious setting during a transition from aquatic to aerial locomotion and gas exchange. Rowing locomotion provides a novel and mechanically intermediate stage for the wings-from-gills and surface-skimming hypotheses for the origin of insect wings and flight.  © 2003 The Linnean Society of London, Biological Journal of the Linnean Society , 2003, 79, 341–349.     

High manoeuvring costs force narrow-winged molossid bats to forage in open space

Molossid bats are specialised aerial-hawkers that, like their diurnal ecological counterparts, swallows and swifts, hunt for insects in open spaces. The long and narrow wings of molossids are considered energetically adapted to fast flight between resource patches, but less suited for manoeuvring in more confined spaces, such as between tree-tops or in forest gaps. To understand whether a potential increase in metabolic costs of manoeuvring excludes molossids from foraging in more confined spaces, we measured energy costs and speed of manoeuvring flight in two tropical molossids, 18 g Molossus currentium and 23 g Molossus sinaloae, when flying in a ~500 m³ hexagonal enclosure (~120 m² area), which is of similar dimensions as typical forest gaps. Flight metabolism averaged 10.21 ± 3.00 and 11.32 ± 3.54 ml CO₂ min⁻¹, and flight speeds 5.65 ± 0.47 and 6.27 ± 0.68 m s⁻¹ for M. currentium and M. sinaloae respectively. Metabolic rate during flight was higher for the M. currentium than for the similar-sized, but broader-winged frugivore Carollia sowelli, corroborating that broad-winged bats are better adapted to flying in confined spaces. These higher metabolic costs of manoeuvring flight may be caused by having to fly slower than the optimal foraging speed, and by the additional metabolic costs for centripetal acceleration in curves. This may preclude molossids from foraging efficiently between canopy trees or in forest gaps. The surprisingly brief burst of foraging activity at dusk of many molossids might be related to the cooling of the air column after sunset, which drives airborne insects to lower strata. Accordingly, foraging activity of molossids may quickly turn unprofitable when the abundance of insects decreases above the canopy.     

Three-dimensional analysis of aphid landing behaviour in the laboratory and field

The final second of the landing approach of black bean aphids, Aphis fabae, was analysed in three dimensions using video techniques. A yellow landing platform was placed upwind or downwind from aphids aggregating under a ceiling light in a laboratory wind tunnel with 10, 20, 30, 40 or 50 cm s^–1 wind speeds, and up-tunnel or down-tunnel in still air. As individual aphids flew to the platform, body orientation (assessed by direct observation) was predominantly into-wind whether the initial flight direction to the landing platform was upwind or downwind. A greater proportion showed into-wind body orientation as wind speed increased. Flight track parameters which differed significantly between wind speeds were the track length, linear start to finish distance, linearity index, horizontal ground speed, speed vertical to the ground, vertical turning rate, and horizontal turning rate. The position of the landing platform was important for track length, linear start to finish distance, horizontal ground speed, three-dimensional turning rate, horizontal turning rate, vertical turning rate, and sinuosity. As wind speed increased above 30 cm s^–1 the ground speed became more consistent and indicated considerable variation in air speed to adjust for ground speed. For the majority of aphids there was a strong preference (88%) for into-wind landings with initial upwind directed flight, while for downwind flights a significant number (55%) of insects reversed initial flight direction and landed into-wind. Field recorded landings showed that 66% of aphids landed into-wind and there was a mean bearing to the wind of 71 ± 42°, a similar finding to wind-tunnel studies.     

Sinking speeds of falling and flying Aphis fabae Scopoli

Abstract. 1. The terminal velocities of freshly anaesthetized and weighed, virginoparous alatae were measured by dropping them into updrafts of known speed. For an average specimen weighing about 0.49 mg the terminal velocity was 1.78 ms^-1 with wings closed and 0.82 ms^-1 with wings fully extended horizontally.
2. Extrapolating from the known terminal velocities of falling spheres of appropriate density, it is concluded that for inertly falling insects of constant shape the terminal velocity will be substantially lower with the wings extended than with them closed for all sizes of insect and that the horizontal distance travelled during a fall will be correspondingly greater.
3. Sudden reflex immobilization and falling was sometimes observed in aphids flying in a laboratory flight chamber, and very occasionally this immobilized state was maintained for many seconds (even during handling) before recovery and renewed flight. There was no evidence of a special falling attitude ('Fall-reflexhaltung') other than a simple 'frozen flight' attitude with wings extended horizontally and legs extended fore and aft while the insect spiralled downwards, abdomen first.
4. The flying aphid's usual response to a coloured surface below it in the flight chamber was not to cease wing-beating and fall but to fly downwards, abdomen first, at speeds up to more than 0.7 m s^-1.     

Skipping flights in Ypthima butterflies (Lepidoptera: Nymphalidae)

The skipping flight patterns of three species of Ypthima (Lepidoptera: Nymphalidae) were analyzed using high‐speed video recordings to clarify how wings move and how driving forces are produced. All three species showed a flight pattern that includes a pause that accounts for about 50% of a flap cycle when their wings completely close after each upstroke. The observed pause causes the “skipping” flight trajectory based on the clap–fling mechanism. Pause duration was correlated with upstroke wing motion, suggesting the contribution of the latter to a long pause duration. This is also supported by the temporal relationship between the wing and body motions. The aerodynamic power necessary for the pause flight was calculated for the three species.     

A modified paranotal theory of insect wing origin

The theory of Kukalova-Peck ('78) is examined and rejected except for the hypothesis of the partially pleural origin of wings. Data suggest that the arthropods ancestral to insects left the water, and that movable precursors of the wings, possibly exopodites, were immobilized and fused with the tergum to form part of the complex paranota. Later, during insect adaptation for flight, parts of the complex paranota were separated secondarily and became wings.     

GENETIC CORRELATIONS AMONG TRAITS DETERMINING MIGRATORY TENDENCY IN THE SAND CRICKET,GRYLLUS FIRMUS

Migration by flight is an important component of the life cycles of most insects. The probability that a given insect will migrate by flight is influenced by many factors, most notably the presence or absence of fully-developed wings and functional flight musculature. Considerable variation has also been reported in the flight propensity of fully-winged individuals with functional flight musculature. We test the hypothesis that these components of migratory tendency are genetically correlated in a wing-dimorhic cricket, Gryllus firmus. Flight propensity and condition of the dorsal longitudinal flight muscles (DLM) are examined in fully-winged (LW) crickets from lines selected for increasing and for decreasing %LW, as well as from unselected control lines. Increased %LW is found to be associated with increased flight propensity among individuals with intact DLM, and with retention of functional DLM. The opposite is true for lines selected for decreased %LW. These results indicate both phenotypic and genetic correlations among behavioral, physiological, and morphological traits determining migratory tendency. We propose that these correlations may result from the multifunctional role of juvenile hormone, which has been reported to influence wing development, flight muscle development and degeneration, and flight propensity. Finally, we discuss the potential influence of genetic correlations for migratory traits on the evolution and maintenance of migratory polymorphisms in insects.     

枯叶蛱蝶扑翼飞行的力学分析

模仿昆虫扑翼飞行的飞行器具有重量轻、质量小、噪音低、效率高、隐蔽性好等优点,在军用、民用领域被广泛地关注与应用.枯叶蛱蝶是典型的扑翼昆虫,在连续上升飞行过程中会出现停顿和跃升的现象.为了研究停顿和跃升现象的产生原因,对枯叶蛱蝶的翅型和扑翼行为进行了力学分析.通过测量鳞翅结构参数,记录飞行行为,运用能量守恒与动量守恒原理,考虑生物能的作用,视空气为不可压缩颗粒,建立了数学模型模拟枯叶蛱蝶飞行情况.结果表明,扑翼行为通过改变飞行动力的动量和分力大小来影响枯叶蛱蝶的飞行轨迹,鳞翅形状则通过改变飞行动力的大小来影响枯叶蛱蝶的飞行轨迹,扑翼行为导致停顿和跃升现象的产生.本文为设计扑翼型飞行器提供了力学仿生学基础与生物学模型,为进一步设计出更优化的仿生飞行器提供科学依据.