Direct Visual Observation of Wing Movements during the Honey Bee Waggle Dance

Recruitment-related behaviours such as waggle dances enable honey bee foragers to inform their nestmates about the location of important resources. However, it is still not known how the information contained in a dance performed in the darkness of the nest is transferred to followers. Although, there are findings indicating that dancing honey bees produce airborne sounds which may convey the information, there has only been indirect evidence that moving wings are the source of these airborne sounds. In this study, honey bee dances were recorded using a high-speed camera in order to directly observe and precisely measure the frequency of wing beats and abdomen wags of dancers. Dancing bees moved their wings for 40.4% of the duration of a waggle run and for only 8.1% of the duration of a circle run. The episodes of wing movements consisted of one to five wing beats and were separated by intervals of motionless wings. The mean frequency of wing beats was 167.0 Hz and significantly differed depending on the number of wing beats in one episode (p < 0.001) and the position of the wings (p = 0.007). The mean frequency of abdomen wags was 14.6 Hz. The mean number of followers was 7.9 and significantly more of them gathered around the abdomens of dancers than around their heads and thoraxes (p = 0.001). The results of this study support the assumption that moving wings are the source of airborne sounds emitted during honey bee dances.     

Do honey bees encode distance information into the wing vibrations of the waggle dance?

An optical technique detected the wing vibration frequency of worker honey bees in an observation hive during the straight run of the waggle dance. Wing oscillation frequencies were recorded from dancing bees after they had visited a feeding station located from 50 to 1600 m from the hive. The bees vibrated their wings more rapidly after they visited nearby stations than when they foraged at more distant feeding stations. For example, the mean frequency of 315 Hz at 50 m dropped to only 207 Hz at 1600 m. Wing vibration frequency appears to be another factor to be added to the elements in the dance known to indicate the distance bees must fly to food sources. These known elements include the duration of the straight run and the number of wagtail movements in the run.     

Soaring and manoeuvring flight of a steppe eagle Aquila nipalensis

We used an onboard inertial measurement unit, together with onboard and ground‐based video cameras, to record the movements of the body, wings and tail of a steppe eagle Aquila nipalensis during wide‐ranging flight. The eagle's flight consisted of a more or less continuous sequence of banked turns, interrupted by occasional wing tucks and roll‐over manoeuvres, and ultimately terminated by a wing‐over manoeuvre leading in to a diving landing approach. The flight configuration of the bird, and its pattern of movement during angular perturbations, together suggest that the eagle is inherently stable in pitch and yaw, and perhaps also in roll. The control inputs used to generate roll moments during banked turns were too subtle to be detected. Control of yaw and pitch during banked turns involved a consistent pattern of tail movement, wherein the tail was spread and depressed immediately before the turn, and then overbanked with respect to the bird during the latter part of the turn. Differential adjustment of wing posture is probably also involved in the control of banked turns, but it was only consistently apparent during more extreme roll manoeuvres. For example, roll‐over and wing‐over manoeuvres were both accomplished by differential changes in the angle of incidence and spread of the wings. In general, however, the bird appeared to maintain positive loading on its wings at all times, except during extreme flight manoeuvres.     

Worker piping in honey bee swarms and its role in preparing for liftoff

Worker piping, previously reported only in hives, was observed in swarms as they prepared to liftoff to fly to a new home. Pipers are excited bees which scramble through the swarm cluster, pausing every second or so to emit a pipe. Each pipe consists of a sound pulse which lasts 0.82 +/- 0.43 s and rises in fundamental frequency from 100-200 Hz to 200-250 Hz. Many. if not all, of the pipers are nest-site scouts. The scouts pipe when it is time to stimulate the non-scouts to warm themselves to a flight-ready temperature (35 degrees C) in preparation for liftoff. The time-course of worker piping matches that of swarm warming, both start at a low level, about an hour before liftoff, and both build to a climax at liftoff. When we excluded pipers from bees hanging in the cool, outermost layer of a swarm cluster, we found that these bees did not warm up. The form of worker piping that we have studied in swarms differs from the form of worker piping that others have studied in hives. We call the two forms "wings-together piping" (in swarms) and "wings-apart piping" (in hives).     

Possible Causes of Variation in Territory Tenure in a Lekking Pompilid Wasp (Hemipepsis ustulata) (Hymenoptera)

Territorial males of the pompilid wasp Hemipepsis ustulata occupy their landmark territories for from less than 1 day to several weeks. Variation in territory tenure could arise if territories differ in their value and cost to defend (the tradeoff hypothesis). If superior sites attract more male competitors, raising the cost ofterritorial defense of these locations, we would expect (1) tenure times to be shorter at top-ranked sites and (2) tenure times to decline in years of high male density and competition. Although mean tenure times for males able to hold territories for at least 2 days were shorter at top-ranked sites, the difference was only statistically significant in one of three years. In the year of highest male density, a significantly higher proportion of all territorial males failed to hold the top-ranked sites for more than a single day; however, mean tenure duration at all occupied sites did not decline in this year. Thus, the tradeoff hypothesis received only partial support. An alternative hypothesis is that variation in male resource holding power, as reflected in male size or wing condition, contributes to differences in territorial tenure. However, although larger males were more likely to become territorial residents at the top-ranked sites, the duration of tenure at these locations was not positively correlated with body size. In addition, although wing condition declined throughout the flight season in concert with a sharp decrease in the duration of tenure at the top-ranked sites, males with fresher wings did not hold territories longer than males whose wings were in poorer condition when they assumed control of a site.     

Swarm behaviour and mate competition in mayflies (Ephemeroptera)

Although mayfly swarms are frequently cited as an example of lekking by insects, little is known about the behaviour of individuals within a swarm, or how mate-selection takes place. A study of five species of mayfly over a period of 10 consecutive years has revealed species-specific differences in the flight pattern of swarming males and in the ability of males to recognize swarms of their own species. Males of four of the five species jostle other males in the swarm at all times except when mating: mating pairs are not jostled. The pattern of jostling varies with the species. Measurements of the sperm content of the vesicula seminalis and of the wing length of members of individual swarms show that larger wing size is positively correlated with the presence of less sperm. The vesicula seminalis is always filled with sperm at the beginning of the imaginal stage and the testes regress before the beginning of the imaginal stage. If the volume of sperm in the vesicula seminalis is a valid index of mating success then males with larger wings have the highest success. Large wings may bestow an advantage during jostling. The males of Ephemera danica , which do not jostle, glide with outspread wings; these outspread wings may attract females, the largest wings being the most attractive. Females of all five species enter the swarm a few at a time, although many females may be resting beneath the swarm. This phased entry may decrease the attraction of the swarm for predators. The number of females in a swarm is not correlated with swarm size, and the factors which enable females to regulate their entry into a swarm remain obscure.     

Female wing spreading as acceptance signal in theDrosophila virilis group of species

Females of manyDrosophila species spread apart their wings prior to copulation. In the present study we found female wing spreading to provoke male copulation attempts inDrosophila virilis-group species, helping the males to attempt copulation when the female is ready to mate. The males of most species, however, rarely responded to female wing spreading by copulation attempt without licking the female genitalia before and/or after female wing spreading bout. Blocking the female genitalia (D. virilis, D. novamexicana) reduces males' tendency to attempt copulation after female wing spreading. In these, and most other species of the group, female wing spreading seems to be an efficient signal only when combined with stimuli from female genitalia.     

Wing flexibility enhances load-lifting capacity in bumblebees

The effect of wing flexibility on aerodynamic force production has emerged as a central question in insect flight research. However, physical and computational models have yielded conflicting results regarding whether wing deformations enhance or diminish flight forces. By experimentally stiffening the wings of live bumblebees, we demonstrate that wing flexibility affects aerodynamic force production in a natural behavioural context. Bumblebee wings were artificially stiffened in vivo by applying a micro-splint to a single flexible vein joint, and the bees were subjected to load-lifting tests. Bees with stiffened wings showed an 8.6 per cent reduction in maximum vertical aerodynamic force production, which cannot be accounted for by changes in gross wing kinematics, as stroke amplitude and flapping frequency were unchanged. Our results reveal that flexible wing design and the resulting passive deformations enhance vertical force production and load-lifting capacity in bumblebees, locomotory traits with important ecological implications.     

Morphology of wing mechanoreceptors involved in the wing retraction reflex in the pteropod mollusc Clione limacina

Tactile stimulation of the wings (parapodia) of actively swimming Clione limacina results in inhibition of swimming and retraction of the wings. Electrophysiological evidence suggests that wing mechanoreceptors have central cell bodies and wide innervation fields in the ipsilateral wing. Scanning electron microscopy of expanded wings reveals ciliary cone processes arranged in a pattern that is similar to the electrophysiologically‐determined innervation fields of wing mechanoreceptors. Transmission electron microscopy suggests that the ciliary cone structures are terminal processes of neuron‐like cells. Three‐dimensional reconstructions of serially‐sectioned terminal processes indicate that cell bodies are not found in the wing epithelium or immediately under the epithelium, further supporting the notion that the wing mechanoreceptors have central cell bodies.     

The wings ofBombyx mori develop from larval discs exhibiting an early differentiated state: a preliminary report

Lepidopteran insects present a complex organization of appendages which develop by various mechanisms. In the mulberry silkworm,Bombyx mori a pair of meso- and meta-thoracic discs located on either side in the larvae gives rise to the corresponding fore- and hind-wings of the adult. These discs do not experience massive cell rearrangements during metamorphosis and display the adult wing vein pattern. We have analysed wing development inB. mori by two approaches, viz., expression of patterning genes in larval wing discs, and regulatory capacities of larval discs following explantation or perturbation. Expression of Nubbin is seen all over the presumptive wing blade domains unlike inDrosophila, where it is confined to the hinge and the wing pouch. Excision of meso- and meta-thoracic discs during the larval stages resulted in emergence of adult moths lacking the corresponding wings without any loss of thoracic tissues suggesting independent origin of wing and thoracic primordia. The expression of wingless and distal-less along the dorsal/ventral margin in wing discs correlated well with their expression profile in adultDrosophila wings. Partially excised wing discs did not showin situ regeneration or duplication suggesting their early differentiation. The presence of adult wing vein patterns discernible in larval wing discs and the patterns of marker gene expression as well as the inability of these discs to regulate growth suggested that wing differentiation is achieved early inB. mori. The timings of morphogenetic events are different and the wing discs behave like presumptive wing buds opening out as wing blades inB. mori unlike evagination of only the pouch region as wing blades seen inDrosophila.     

A novel method of behavioural thermoregulation in butterflies

Abstract The requirement for efficient thermoregulation has directed the coevolution of specialized morphological and behavioural traits in ectotherms. Adult butterflies exhibit three thermoregulatory mechanisms, termed dorsal, lateral and reflectance basking. In this study, we investigate a potential fourth mechanism whereby individuals perch with their wings fully spread and angled downwards such that the margins are appressed to the substrate. We find that mate‐locating male Hypolimnas bolina (L.) (Nymphalidae) adopt this posture when operational thoracic temperatures are lowest (less than approximately 34 °C). As thoracic temperature increases, males perch with wings increasingly closed and ultimately select shaded microhabitats. Using thermocouple‐implanted dead models, we show that appressed posture individuals warm faster than those adopting the conventional dorsal‐basking (horizontal wing) posture. This thermal advantage is not mitigated by shading of the outer 60–70% of the wing area, which suggests that – as with the conventional dorsal posture – only the basal wing surfaces contribute to heat gain via the absorption of solar irradiation. These investigations suggest that appression represents a novel extension of conventional dorsal basking behaviour in butterflies.     

The multiplication and spread of sacbrood virus of bees

Sacbrood virus multiplied without causing symptoms in adult bees when it was injected into them or when it was fed to young individuals. More virus accumulated in heads of infected bees than elsewhere in their bodies, and much was in their hypopharyngeal glands. The extract of each infected head contained about 10²medial lethal doses (LD 50s) of sacbrood virus for larvae when given in their food. The infective dose of sacbrood virus by injection for adults was about 10^-4of the LD 50 in food for larvae. The infective dose by mouth for adults was about 10²LD 50s for larvae, but bees older than 4–8 days could not be infected this way. Infection did not spread between adults but is probably transmitted in nature from infected adults to larvae and back to young adults that ingest remains of larvae killed by sacbrood. The youngest adult bees infected with sacbrood ate little pollen and lived only about 3 weeks in the laboratory, as did bees receiving no pollen, whereas bees fed with ample pollen lived 9 weeks.     

Deformed wing virus in western honey bees (Apis mellifera) from Atlantic Canada and the first description of an overtly-infected emerging queen

Deformed wing virus (DWV) in western honey bees (Apis mellifera) often remains asymptomatic in workers and drones, and symptoms have never been described from queens. However, intense infections linked to parasitism by the mite Varroa destructor can cause worker wing deformity and death within 67 h of emergence. Ten workers (eight with deformed wings and two with normal wings) and three drones (two with deformed wings and one with normal wings) from two colonies infected with V. destructor from Nova Scotia, Canada, and two newly-emerged queens (one with deformed wings and one with normal wings) from two colonies infected with V. destructor from Prince Edward Island, Canada, were genetically analyzed for DWV. We detected DWV in all workers and drones, regardless of wing morphology, but only in the deformed-winged queen. This is the first report of DWV from Atlantic Canada and the first detection of a symptomatic queen with DWV from anywhere.     

中国东方蜜蜂的形态分化(英文)

【目的】遗传分化研究是认识蜜蜂形态多样性和适应性进化的重要环节,是确定蜜蜂资源管理单位和保护单位的前提,有助于保护蜜蜂的遗传资源。本研究通过分析形态分化,研究中国东方蜜蜂Apiscerana在中国地理环境下的遗传分化和遗传资源分布。【方法】从我国所有东方蜜蜂分布区102个采样点共采集6 147头东方蜜蜂工蜂,每一采样点10~20群中取60头工蜂进行解剖,测定与翅、个体大小、后足和体色相关的33个形态特征,进行多变量形态统计分析,划分形态类群。同时对分出的不同东方蜜蜂类群的形态特征及分布模式进行分析。【结果】根据判别分析和主成分分析的聚类结果,我国东方蜜蜂分为14个形态类群。有5个类群具有较小的个体大小。海南类群个体最小,其次为滇南类群,台湾类群,南方类群和北方类群。这5个类群之间在吻长、前翅长、前翅第3亚缘室结构、体色和蜡镜长上存在显著差异。长白类群具有最大的肘脉指数、蜡镜和第5背板绒毛带宽。而西藏波密类群具有全国最小的第五背板绒毛带宽。西北类群具有最长的后足。川西高原的5个形态类群具有个体大、体色黑等特点。其中,巴塘类群肘脉指数(3.0169)全国最小,个体大小全国最大。阿坝类群具有仅次于长白类群的肘脉指数,且翅长和第七腹板最大。德荣类群体色最黑。雅江类群具有独特的翅脉角 (A4, N23, E9和J10最小,B4最大)。川滇类群在川西高原个体最小。【结论】本研究在全面收集我国所有东方蜜蜂分布区样本,尤其是西藏波密、台湾省和川西高原的珍贵样本的基础上,进行了东方蜜蜂形态测量学分析。在我国共发现东方蜜蜂14个形态类群：海南类群、滇南类群、长白类群、台湾类群、波密类群、阿坝类群、巴塘类群、德荣类群、雅江类群、川滇类群、川贵类群、西北类群、南方类群以及北方类群。研究结果为中国东方蜜蜂遗传资源的保护和遗传资源的开发利用提供理论基础。     

Variation in male wing song characters inDrosophila plantibia (Hawaiian picture-wingedDrosophila group)

The males of most species of the HawaiianDrosophila planitibia group produce songs when vibrating their wings during courtship. In four of the most recently evolved species,D. differens, D. planitibia, D. heteroneura, andD. silvestris, these songs are simple in structure and possess a higher and more variable carrier frequency than the songs of the more ancestral species of the group. In the present paper, we studied the variation in wing song production and song characters in aD. planitibia population. Some males vibrated their wings at a very low amplitude or slow speed, producing no detectable sound. Other males produced sound bursts varying in carrier frequency and burst length. The carrier frequency of the song depended mainly on the wing posture of the male during wing vibrations and was consistent for individual males. Variation between males of different isofemale progenies was not significant in any measured song trait. Songs of the males recorded in the present study differed, however, from songs of the males of a laboratory strain recorded earlier.     

PATTERNS OF QUANTITATIVE VARIATION IN LEPIDOPTERAN WING MORPHOLOGY: THE CONVERGENT GROUPS HELICONIINAE AND ITHOMIINAE (PAPILIONOIDEA: NYMPHALIDAE)

Wing morphology has historically been a major focus in taxonomic and evolutionary studies of lepidopterans. However, general patterns of quantitative variation and diversification in wing sizes and shapes and the factors underlying them have been unexplored. A morphometric study of wing variation in the convergent heliconine and ithomine butterflies reveals remarkable similarities, both in their morphologies at a given size and in their patterns of allometry and variability. The groups differ primarily in the relative lengths of inner and outer forewing margins, with larger species being more similar across groups than smaller ones. Allometric size-scaling variation accounts for more than 90% of the total morphological variation in the two groups and thus seems to be the major determinant of wing shape. Forewings and hind wings are isometric in size (area) with respect to one another; however, wing shape within and among groups is significantly allometric, resulting in considerable shape differences between small and large species. A strong trend of increasing variability from anterior to posterior along the wings is consistent with hypotheses of aerodynamic constraint. Wings and bodies represent classical morphological “character suites” in that size and shape variation are more tightly correlated within suites than among them. Such complexes argue against the overriding importance of aerodynamic factors, such as wing load and muscle development, in constraining gross morphology.     

Distribution of deformed wing virus within honey bee (Apis mellifera) brood cells infested with the ectoparasitic mite Varroa destructor

The distribution of deformed wing virus (DWV) in adult female Varroa destructor and in their progeny in relation to the pupal host bee was investigated to evaluate acquisition and transfer of DWV by the mites. The results clearly show that adult female mites regularly act as competent vectors of DWV, however, they do not acquire or transfer virus on all possible occasions. Mother mites may contain DWV while the pupal host remains free from overt infection and both mother mites and mite progeny may not acquire detectable amounts of DWV from an infected host bee. However, a majority of mites feeding on pupae that emerge with deformed wings will contain DWV. The data also demonstrates that both adult and immature mite progeny most likely acquire DWV from DWV-infected host bees and not from their mother mites. Possible explanations for the obtained results are discussed. This revised version was published online in July 2006 with corrections to the Cover Date.     

The costae presenting in high-temperature-induced <Emphasis Type="Italic">vestigial</Emphasis> wings of <Emphasis Type="Italic">Drosophila</Emphasis>: implications for anterior wing margin formation

It has long been noted that high temperature produces great variation in wing forms of the vestigial mutant of Drosophila. Most of the wings have defects in the wing blade and partially formed wing margin, which are the result of autonomous cell death in the presumptive wing blade or costal region of the wing disc. The vestigial gene (vg) and the interaction of Vg protein with other gene products are well understood. With this biochemical knowledge, reinvestigations of the high-temperature-induced vestigial wings and the elucidation of the molecular mechanism underlying the large-scale variation of the wing forms may provide insight into further understanding of development of the wing of Drosophila. As a first step of such explorations, I examined high-temperature-induced (29°C) vestigial wings. In the first part of this paper, I provide evidences to show that the proximal and distal costae in these wings exhibit regular and continuous variation, which suggests different developmental processes for the proximal and distal costal sections. Judging by the costae presenting in the anterior wing margin, I propose that the proximal and distal costal sections are independent growth units. The genes that regulate formation of the distal costal section also strongly affect proliferation of cells nearby; however, the same phenomenon has not been found in the proximal costal section. The distal costal section seems to be an extension of the radius vein. vestigial, one of the most intensely researched temperature-sensitive mutations, is a good candidate for the study of marginal vein formation. In the second part of the paper, I regroup the wing forms of these wings, chiefly by comparison of venation among these wings, and try to elucidate the variation of the wing forms according to the results of previous work and the conclusions reached in the first part of this paper, and provide clues for further researches.     

Uric acid metabolism during pupal-adult development of Pieris brassicae

Uric acid metabolism has been investigated during the pupal and adult stages of Pieris brassicae. Uric acid and its main metabolite, allantoic acid, have been quantified in various organs (fat body, gut, wings) during development, in order to determine synthesis, degradation, and transport phenomena. Both labelling experiments (using 2-¹⁴C uric acid, guanine, and guanosine) and enzymatic studies (xanthine dehydrogenase, guanine deaminase, and uricase) were performed.Labelled uric acid, when injected into a young pupa, accumulates preferentially into the fat body, and its degradation leads to an increase in allantoic acid, which is found chiefly in imaginal structures (wings, heads, body wall). Since uricase is present only in low levels through the pupal stage, only a small fraction of uric acid is metabolized.In the developing pharate adult, uric acid is transported via the haemolymph from fat body to the wings and gut. Male wings accumulate more uric acid than female wings. At emergence, a large amount of uric acid and most of the allantoic acid are excreted into the meconium, but not together; uric acid is excreted into the so-called ‘meconium 1’ containing ommochromes, whereas its metabolite is eliminated only after wing expansion into ‘meconium 2’, a colourless fluid. Shortly before emergence, the fat body recovers its ability to synthesize uric acid, a fraction of which is excreted within ‘meconium 1’.During adult life, the synthesis of uric acid occurs in the fat body and ovaries, where it is especially abundant. Ageing organs (wings, heads, testes) accumulate it markedly. A small fraction is excreted together with allantoic acid by the butterfly.Purine catabolism pathways have been investigated, showing that in guanine derivatives, the freebase state of guanine leads quickly to uric acid (and its metabolites), whereas ¹⁴C-guanosine may be transformed into nucleotide and incorporated efficiently into wing pteridines when it is injected at the time of adult pigmentation.Another purine derivative, identified as adenosine, has been shown to accumulate in male fat body just before adult emergence. Its amount increases during the first days of emerged adult life, and it corresponds to an alternative pathway of purine catabolism. Its absence in females is related to development of the ovaries.