Does the circadian clock drift when pilots fly multiple transpacific flights with 1- to 2-day layovers?

On trips with multiple transmeridian flights, pilots experience successive non-24 h day/night cycles with circadian and sleep disruption. One study across a 9-day sequence of transpacific flights (no in-flight sleep, 1-day layovers between flights) reported an average period in the core body temperature rhythm of 24.6 h (circadian drift). Consequently, pilots were sometimes flying through the circadian performance nadir and had to readapt to home base time at the end of the trip. The present study examined circadian drift in trip patterns with longer flights and in-flight sleep. Thirty-nine B747-400 pilots (19 captains, 20 first officers, mean age = 55.5 years) were monitored on 9- to 13-day trips with multiple return flights between East Coast USA and Japan (in 4-pilot crews) and between Japan and Hawaii (in 3-pilot crews), with 1-day layovers between each flight. Measures included total in-flight sleep (actigraphy, log books) and top of descent (TOD) measures of sleepiness (Karolinska Sleepiness Scale), fatigue (Samn–Perelli Crew Status Check) and psychomotor vigilance task (PVT) performance. Circadian rhythms of individual pilots were not monitored. To detect circadian drift, mixed-model analysis of variance examined whether for a given flight, total in-flight sleep and TOD measures varied according to when the flight occurred in the trip sequence. In addition, sleep propensity curves for pre-trip and post-trip days were examined (Chi-square periodogram analyses). Limited data suggest that total in-flight sleep of relief crew at landing may have decreased across successive East Coast USA–Japan (flights 1, 3, 5 or 7; median arrival 03:45 Eastern Daylight Time (EDT)). However, PVT response speed at TOD was faster on East Coast USA–Japan flights later in the trip. On these flights, circadian drift would result in flights later in the trip landing closer to the evening wake maintenance zone, when sleep is difficult and PVT response speeds are fastest. On Japan–East Coast USA flights (flights 2, 4, 6 or 8; median arrival time 14:52 EDT), PVT response speeds were slower on flight 8 than on flight 2. Circadian drift would move these arrivals progressively earlier in the SCN pacemaker cycle, where PVT response speeds are slower. Across the five post-trip days, 12 pilots (Group A) immediately resumed their pre-trip sleep pattern of a single nocturnal sleep episode; 9 pilots (Group B) had a daytime nap on most days that moved progressively earlier until it merged with nocturnal sleep and 17 pilots (Group C) had nocturnal sleep and intermittent naps. Chi-square periodogram analyses of the sleep propensity curves for each group across baseline and post-trip days suggest full adaptation to EDT from post-trip day 1 (dominant period = 24 h). However, in Groups B and C, the patterns of split sleep post-trip compared to pre-trip suggest that this may be misleading. We conclude that the trends in total in-flight sleep and significant changes in PVT performance speed at TOD provide preliminary evidence for circadian drift, as do persistent patterns of split sleep post-trip. However, new measures to track circadian rhythms in individual pilots are needed to confirm these findings.     

Pointed wings, low wingloading and calm air reduce migratory flight costs in songbirds

Migratory bird, bat and insect species tend to have more pointed wings than non-migrants. Pointed wings and low wingloading, or body mass divided by wing area, are thought to reduce energy consumption during long-distance flight, but these hypotheses have never been directly tested. Furthermore, it is not clear how the atmospheric conditions migrants encounter while aloft affect their energy use; without such information, we cannot accurately predict migratory species' response(s) to climate change. Here, we measured the heart rates of 15 free-flying Swainson's Thrushes (Catharus ustulatus) during migratory flight. Heart rate, and therefore rate of energy expenditure, was positively associated with individual variation in wingtip roundedness and wingloading throughout the flights. During the cruise phase of the flights, heart rate was also positively associated with wind speed but not wind direction, and negatively but not significantly associated with large-scale atmospheric stability. High winds and low atmospheric stability are both indicative of the presence of turbulent eddies, suggesting that birds may be using more energy when atmospheric turbulence is high. We therefore suggest that pointed wingtips, low wingloading and avoidance of high winds and turbulence reduce flight costs for small birds during migration, and that climate change may have the strongest effects on migrants' in-flight energy use if it affects the frequency and/or severity of high winds and atmospheric instability.     

Biotelemetry of New World thrushes during migration: Physiology, energetics and orientation in the wild

Billions of songbirds migrate between continents each year,but we have yet to obtain enough information on in-flight physiologyand energetics to fully understand the migratory behavior ofany one species. New World Catharus thrushes are common nocturnalmigrants amenable to biotelemetry, allowing us to measure physiologicalparameters during migratory flight in the wild. Here, we reviewwork by the authors on Catharus thrush in-flight physiologyduring spring migration in continental North America and presentnew data on individual variation in energy use during migratoryflight. Previous work demonstrated that (1) a number of simplebehavioral rules are sufficient to explain the initiation ofindividual migratory flights made by Catharus thrushes, (2)the thrushes used a magnetic compass to orient during the nightrather than celestial cues and that they calibrated this magneticcompass each day using cues associated with the setting sun,(3) in total, Catharus thrushes used approximately twice asmuch energy during stopovers than they used during migratoryflight, and (4) thrushes may use more energy when thermoregulatingon cold days than on days when they make short migratory flights.Recently, we built upon this work and used newly-developed transmittersto measure heart rate, wingbeat frequency and respiration rateof free-flying Swainson's Thrushes (C. ustulatus). We founda large amount of between-individual variation in average heartrate after ascent (range 12.06–14.81 Hz, mean ±SD, 13.48 ± 0.75, n = 10), average wingbeat frequencyafter ascent (10.25–11.75 Hz, 10.82 ± 0.49, n =10), and the difference between the two variables (1.5–3.84Hz, 2.53 ± 0.76, n = 8). Both heart rate and wingbeatfrequency were significantly higher during ascent than laterin the flight. We propose biotelemetry as a means to understandenergetic trade-offs and decisions during natural migratoryflight in songbirds. To further our knowledge of intercontinentalsongbird migration and the connectivity between wintering andbreeding sites, we outline plans for a satellite-based globaltracking system for <1 g transmitters.     

Bone mineral and lean tissue loss after long duration space flight

The loss of bone and muscle is a major concern for long duration space flight. In December of 1989, we established a collaboration with Russian colleagues to determine the bone and lean tissue changes in cosmonauts before and after flights on the Mir space station lasting 4-14.4 months. Eighteen crew members received a lumbar spine and hip DEXA scan (Hologic 1000W) before and after flight; 17 crew members received an additional whole body scan. All results were expressed as percent change from baseline per month of flight in order to account for the different flight times. The pre-and post-flight data were analyzed using Hotelling's T(2) for 3 groups of variables: spine, neck of femur, trochanter; whole body BMD and subregions; lean (total, legs, arms) and fat (total only). A paired t-test was used as a follow-up to the Hotelling's T(2) to identify the individual measurements that were significantly different. These data define the rate and extent of bone and lean tissue loss during long duration space flight and indicate that the current in-flight exercise program is not sufficient to completely ameliorate bone and muscle loss during weightlessness.     

Changes in hemodynamic and post-flights orthostatic tolerance of cosmonauts under application of the preventive device--thigh cuffs bracelets in short-term flights

Specific aims: to evaluate the influence of the use thigh cuffs "Bracelet" on the hemodynamic adaptation to microgravity during short-term (up to a month) space flights, in-flight tolerance to LBNP-tests and post-flight orthostatic tolerance. 6 cosmonauts applied and 7 others did not apply the occlusive cuffs when on flight. The "Bracelet" device notably relieved the cosmonauts from the subjective discomfort following by the blood redistribution at initial period of exposure to microgravity. It was established that "Bracelet" lessened shifts in central and peripheral hemodynamics typical for exposure to microgravity, venous stasis in the cervical-cephalic region in particular. There were no differences between the hemodynamic reaction on LBNP-test in cosmonauts who applied and not applied "Bracelet" during short-term flights. The objective data are received, that the application of the device during short-term space flight does not make negative effects on post-flight orthostatic tolerance.     

Energy Expenditure and Metabolic Changes of Free-Flying Migrating Northern Bald Ibis

Many migrating birds undertake extraordinary long flights. How birds are able to perform such endurance flights of over 100-hour durations is still poorly understood. We examined energy expenditure and physiological changes in Northern Bald Ibis Geronticus eremite during natural flights using birds trained to follow an ultra-light aircraft. Because these birds were tame, with foster parents, we were able to bleed them immediately prior to and after each flight. Flight duration was experimentally designed ranging between one and almost four hours continuous flights. Energy expenditure during flight was estimated using doubly-labelled-water while physiological properties were assessed through blood chemistry including plasma metabolites, enzymes, electrolytes, blood gases, and reactive oxygen compounds. Instantaneous energy expenditure decreased with flight duration, and the birds appeared to balance aerobic and anaerobic metabolism, using fat, carbohydrate and protein as fuel. This made flight both economic and tolerable. The observed effects resemble classical exercise adaptations that can limit duration of exercise while reducing energetic output. There were also in-flight benefits that enable power output variation from cruising to manoeuvring. These adaptations share characteristics with physiological processes that have facilitated other athletic feats in nature and might enable the extraordinary long flights of migratory birds as well.     

Developmental testing of the Advanced Animal Habitat to determine compatibility with rats and mice

The Research Animal Holding Facility (RAHF) and the Animal Enclosure Module (AEM) have housed rats during Space Shuttle flights since the 1980s, but the operational constraints of the hardware have limited the scientific return from these Shuttle flights. The RAHF provides environmental control and monitoring for 24 rats with in-flight animal access, but it must be flown in the Spacelab. Due to the infrequent availability of Spacelab flights, rodent experiments rely heavily on the AEM. Unfortunately, the AEM supports only six rats, has no environmental control and provides no animal access in flight. The Advanced Animal Habitat (AAH) is being developed to support up to 12 adult rats or 30 adult mice for up to 30 days, provide active temperature control, animal telemetry and on-orbit video, record environmental parameters in the animal cage, and provide in-flight animal access in the Middeck, the Spacelab or the Space Station. To ensure the AAH can meet these requirements, animal testing is being conducted with rats and mice in every step of development. Testing began with the cage configuration.     

Wind tunnel as a tool in bird migration research

Wind tunnels, in which birds fly against an artificially generated air flow, have since long been used to evaluate aerodynamic properties of steady bird flight. A new generation of wind tunnels has also allowed the many processes associated with migratory flights to be studied in captivity. We review how wind tunnel studies of aerodynamics and migratory performance together have helped advancing our understanding of bird migration. Current migration theory is based on the power‐speed relationship of flight as well as flight range equations, both of which can be evaluated using birds flying in wind tunnels. In addition, and depending on wind tunnel properties, performance during gliding and climbing flight, and effects of air pressure, humidity and turbulence on bird flight has been measured. Long‐distance migrant species have been flown repeatedly for up to 16 h non‐stop, allowing detailed studies of the energy expenditure, fuel composition, protein turnover, water balance, immunocompetence and stress associated with sustained migratory flights. In addition, wind tunnels allow the fuelling periods between migratory flights to be studied from new angles. We end our review by suggesting several important topics for future wind tunnel studies, ranging from on of the key questions remaining, the efficiency at which chemical power in converted to mechanical power, to new useful avenues, such as improving and calibrating the techniques used for tracking of individual birds in the wild.     

Medical care for Russian cosmonauts on board the ISS

Established with the personal participation of O.G. Gazenko, the Russian system of medical care for cosmonauts has been largely preserved to this day. The system was fully functional on board the orbital complex Mir and, with appropriate modifications, has been adopted as the core of the medical care for Russian members of ISS crews. In 2000–2008, 22 cosmonauts were members of 17 ISS missions lasting from 140 to 216 days. The main functions of the medical care system were to control health, physical, and mental performance, and to support space research. Readaptation to normal gravity was, in most cases, similar to what has been typical on the return from Russian orbital stations; some deviations are accounted for by the use of in-flight countermeasures. The paper presents some aspects of the theoretical work of Academician Gazenko in the field of medical care in space flights. It outlines the principles of ISS medical management. The integrated medical support system combines medical equipment and items available in the Russian and U.S. segments; the integrated medical group consists of flight surgeons, medical experts, and biomedical engineers of international partners and coordinates the planning and implementation of medical operations. In addition, challenges of health care in the phase of ISS operation are defined.     

Activity and migratory flights of individual free‐flying songbirds throughout the annual cycle: method and first case study

We describe a method and device (< 1.2 g) for recording, processing and storing data about activity and location of individuals of free‐living songbirds throughout the annual cycle. Activity level was determined every five minutes from five 100 ms samples of accelerometer data with 5 s between the sampling events. Activity levels were stored on an hourly basis throughout the annual cycle, allowing periods of resting/sleep, continuous flight and intermediate activity (foraging, breeding) to be distinguished. Measurements from a light sensor were stored from preprogrammed key stationary periods during the year to provide control information about geographic location. Successful results, including annual actogram, were obtained for a red‐backed shrike Lanius collurio carrying out its annual loop migration between northern Europe and southern Africa. The shrike completed its annual migration by performing > 66 (max. 73) nocturnal migratory flights (29 flights in autumn and > 37, max. 44, in spring) adding up to a total of > 434 (max. 495) flight hours. Migratory flights lasted on average 6.6 h with maximum 15.9 h. These flights were aggregated into eight travel episodes (periods of 4–11 nights when flights took place on the majority of nights). Daytime resting levels were much higher during the winter period compared to breeding and final part of spring migration. Daytime resting showed peaks during days between successive nocturnal flights across Sahara, continental Africa and the Arabian Peninsula, indicating that the bird was mostly sleeping between these long migratory flights. Annual activity and flight data for free‐living songbirds will open up many new research possibilities. Main topics that can be addressed are e.g. migratory flight performance (total flight investment, numbers and characteristics of flights), timing of stationary periods, activity patterns (resting/sleep, activity level) in different phases of the annual cycle and variability in the annual activity patterns between and within individuals.     

Aircrew fatigue in trans-Atlantic morning and evening flights

The aim of the investigation was to compare sleepiness and sleep on westward morning and evening flights. Seven morning-crew pilots and seven evening-crew pilots participated. Data were collected before, during, and after outward-bound (westward) and homeward-bound (eastward) flights across six time zones. A sleep/wake diary (with repeated sleepiness and performance ratings) and wrist actigraphy were used for data collection. Maximum sleep was obtained after return and minimum sleep before the outward-bound flights. Actigraphy measures and sleep efficiency over the course of the study showed no significant differences between the morning and evening crews. There was a trend for a significant effect of morning vs. evening flight for time with heavy eyelids, with the homeward-bound flight showing more time with heavy eyelids. There were no significant differences between morning and evening crews with regard to napping during the flight. The duration of wakefulness was longer for the evening flight crew. There were significant interactions for Karolinska sleepiness scale (KSS) self-ratings on both the outward-bound and homeward-bound flights, and KSS was elevated during a considerable portion of the evening flights. Rated performance showed a significant time effect, but there was no difference in self-ratings between morning and evening crews. Evening flights involve higher levels of sleepiness than morning flights, presumably because of the close proximity in time to the circadian trough of alertness.     

Considerations for non-invasive in-flight monitoring of astronaut immune status with potential use of MEMS and NEMS devices

The dynamics of how astronauts' immune systems respond to space flight have been studied extensively, but the complex process has not to date been thoroughly characterized, nor have the underlying principles of what causes the immune system to change in microgravity been fully determined. Statistically significant results regarding overall immunological effects in space have not yet been established due to the relatively limited amount of experimental data available, and are further complicated by the findings not showing systematically reproducible trends. Collecting in vivo data during flight without affecting the system being measured would increase understanding of the immune response process.The aims of this paper are to briefly review the current knowledge regarding how the immune system is altered in space flight; to present a group of candidate biomarkers that could be useful for in-flight monitoring and give an overview of the current methods used to measure these markers; and finally, to further establish the need and usefulness of incorporating real-time analytical techniques for in-flight assessment of astronaut health, emphasizing the potential application of MEMS/NEMS devices.     

It is time to move: linking flight and foraging behaviour in a diving bird

Although the adaptive value of flight may seem obvious, it is the most difficult behaviour of birds to monitor. Here, we describe a technique to quantify the frequency and the duration of flights over several months by implanting a data logger that records heart rate (fH), hydrostatic pressure (diving depth) and the body angle of a large sea duck species, the common eider (Somateria mollissima). According to the mean fH recorded during flight and the parameters recorded to identify the fH flight signature, we were able to identify all flights performed by 13 individuals during eight months. We cumulated local flight time (outside migrations) and found that activity occurs primarily during dawn and morning and that flying activities are strongly related to diving activities (Pearson's r=0.88, permutation test p<0.001). This relationship was interpreted as a consequence of living in a dynamic environment where sea currents move the ducks away from the food patches. We believe that the technique described here will open new avenues of investigation in the adaptive value of flight.     

Foraging behaviour and time allocation of chick-rearing Razorbills Alca torda at Græsholmen, central Baltic Sea

A new type of bird-borne data logger, which stores data from flight and depth sensors at pre-set intervals, was used to investigate the foraging pattern and diving behaviour of chick-rearing Razorbills Alca torda breeding on the islet of Græsholmen (central Baltic Sea, Denmark). The instruments recorded all relevant events in the 35 foraging trips accomplished by six different individual birds; a seventh bird, equipped with a direction recorder, provided information on directional preferences exhibited on seven different trips. A foraging trip usually consisted of a number of flights interrupted by a small number of dives probably performed to explore the site for prey availability. True foraging occurred during the last stops in the outbound trip, after which the bird returned to the nest with a single flight or a sequence of a few flights. The duration of nocturnal trips was significantly longer than diurnal trips, possibly due to a preference for the familiar marine environment shown by birds when they are not 'on duty' in the nest. The majority of dives consisted of V-shaped dives in which birds descend to a maximum depth and then start ascending. A clear diurnal variation of the dive depth, which never exceeded 43 m, was recorded. Our results show that the new types of recording devices can be used to answer basic questions about the foraging strategies of marine birds.     

Aircrew Fatigue in Trans‐Atlantic Morning and Evening Flights

The aim of the investigation was to compare sleepiness and sleep on westward morning and evening flights. Seven morning‐crew pilots and seven evening‐crew pilots participated. Data were collected before, during, and after outward‐bound (westward) and homeward‐bound (eastward) flights across six time zones. A sleep/wake diary (with repeated sleepiness and performance ratings) and wrist actigraphy were used for data collection. Maximum sleep was obtained after return and minimum sleep before the outward‐bound flights. Actigraphy measures and sleep efficiency over the course of the study showed no significant differences between the morning and evening crews. There was a trend for a significant effect of morning vs. evening flight for time with heavy eyelids, with the homeward‐bound flight showing more time with heavy eyelids. There were no significant differences between morning and evening crews with regard to napping during the flight. The duration of wakefulness was longer for the evening flight crew. There were significant interactions for Karolinska sleepiness scale (KSS) self‐ratings on both the outward‐bound and homeward‐bound flights, and KSS was elevated during a considerable portion of the evening flights. Rated performance showed a significant time effect, but there was no difference in self‐ratings between morning and evening crews. Evening flights involve higher levels of sleepiness than morning flights, presumably because of the close proximity in time to the circadian trough of alertness.     

Barometer logging reveals new dimensions of individual songbird migration

Recent advances in tracking technology are based on the use of miniature sensors for recording new aspects of individual migratory behaviour. In this study, we have used activity data loggers with barometric and temperature sensors to record the flight altitudes as well as ground elevations during stationary periods of migratory songbirds. We tracked one individual of red‐backed shrike and one great reed warbler along their autumn migration from Europe to Africa. Both individuals performed their migration stepwise in travel segments and climbed most metres during the passage across the Mediterranean Sea and the Sahara Desert and least metres during the first flight segment in Europe. The great reed warbler reached its highest flight altitude of 3950 m a.s.l. during the travel segment from Europe to west Africa, while the red‐backed shrike reached 3650 m a.s.l as maximum flight altitude during its travel segment from Sahel to southern Africa. Both individuals used both lowlands and highlands for resting periods along their migrations. Furthermore, temperature decreased with increasing altitude during migratory flights for both individuals, highlighting the potential to determine flight duration from temperature measurements. Finally, we discuss how barometric data could be used to investigate birds’ responses to changes in air pressure as a cue for departures on migratory flights. This new technique, i.e. using a miniature data logger with barometric pressure sensor to estimate flight altitudes and ground elevations, will open up new avenues for research and importantly advance our understanding on how small birds behave during migratory flights.     

Heart rate and rate of oxygen consumption during flight of the barnacle goose, Branta leucopsis

We report the first measurements of heart rate (f(H)) and the rate of oxygen consumption (V(O(2))) during flights from a species of bird larger than 500 g. V(O(2))was obtained from nine forward flapping flights of 8.9 min mean duration at a mean speed of 13.2 m s(-1) performed by three barnacle geese of mean mass 1.68 kg. Mean V(O(2))was 332 ml min(-1)or 201 ml min(-1) kg(-1). Sixteen flights were obtained from two of these birds equipped with heart rate data loggers, both when they were wearing a V(O(2)) mask and when they were not. During flights with the mask (mean duration 7.4 min), mean f(H) was 472 beats per min and during flights without the mask (mean duration 8.0 min) it was 391 beats per min. Heart rate was also measured in another goose flying without a respiratory mask and mean f(H) for all the three birds (mean mass 1.7 kg) flying without a mask for an average of 7.9 min at 13 m s(-1) was 378 beats per min. Resting f(H) for these three birds was 79 beats per min. The values of f(H) during flight are greater than those obtained from the same species during their autumn migration from Spitsbergen to southern Scotland. The possible reasons for this are discussed.     

From the flight of Yu.A. Gagarin to the contemporary piloted space flights and exploration missions

The first human flight to space performed by Yu.A. Gagarin on April 12, 1961 was a crucial event in the history of cosmonautics that had a tremendous effect on the further progress of human civilization. Gagarin’s flight had been preceded by targeted biomedical research with the use of diverse biological objects on board rockets and artificial satellites. This research led to the conclusion on the fundamental possibility for humans to fly in space. After a series of early flights and improvements in the medical support system, space missions to the Salyut and Mir stations were gradually extended to record durations. The foundations of this extension were laid by systemic research in the fields of space biomedicine and related sciences. The current ISS system of the crew’s medical care has been successful in maintaining the health and performance of cosmonauts, as well as in providing the conditions for research in various fields related to space flights. The ISS abounds in opportunities for the preparation for piloted interplanetary missions. At the same time, the ground-based simulation of a mission to Mars is a venue for carrying out scientific and technological experiments in space biomedicine.     

Wild geese do not increase flight behaviour prior to migration

Hypertrophy of the flight muscles is regularly observed in birds prior to long-distance migrations. We tested the hypothesis that a large migratory bird would increase flight behaviour prior to migration, in order to cause hypertrophy of the flight muscles, and upregulate key components of the aerobic metabolic pathways. Implantable data loggers were used to record year-round heart rate in six wild barnacle geese (Branta leucopsis), and the amount of time spent in flight each day was identified. Time in flight per day did not significantly increase prior to either the spring or the autumn migration, both between time periods prior to migration (5, 10 and 15 days), or when compared with a control period of low activity during winter. The lack of significant increase in flight prior to migration suggests that approximately 22 min per day is sufficient to maintain the flight muscles in condition for prolonged long-distance flight. This apparent lack of a requirement for increased flight activity prior to migration may be attributable to pre-migratory mass gains in the geese increasing workload during short flights, potentially prompting hypertrophy of the flight muscles.     

Effect of Adult Experience on in-Flight Orientation to Plant and Plant–Host Complex Volatiles inAphidius erviHaliday (Hymenoptera, Braconidae)

The effect of adult experience on in-flight orientation to plant–host complex volatiles byAphidius erviHaliday was studied in a wind tunnel bioassay, usingAcyrthosiphon pisum(Harris), maintained on broad bean plants (Vicia faba) as host. A short oviposition experience (15 s) on the plant–host complex (PHC) was sufficient to induce a drastic decrease of flight propensity and stimulated a foraging behavior characterized by intense walking activity. However, flight activity resumed to normal levels 1 h after the oviposition experience on the PHC occurred. For parasitoids conditioned on the PHC for at least 1 min the recorded proportion making oriented flights to the PHC was significantly higher than that for naive females. In contrast, oviposition experience in the absence of plant material did not influence theA. erviflight response. Oviposition attempts on aphid dummies without egg release did not reduce flight activity. WhenA. ervifemales were exposed to glass beads coated withAc. pisumcornicle secretion, a priming effect was observed, resulting, compared with naive females, in a significantly higher rate of oriented flights to the PHC. In contrast, oviposition attempts visually induced by colored aphid dummies did not influence flight behavior. A strong reaction to volatile cues from uninfested plants was induced by oviposition experience on newly infested broad bean plants. This appears to be a case of associative learning. In fact, uninfested broad bean plants are basically unattractive to naiveA. ervifemales. The results demonstrate that adult experience has a considerable influence onA. ervibehavior and may have important implications for biological control of natural pest aphid populations.