bluuebunny/crossref_metadata_2025 huggingface dataset:
Klinokinetic and klinotactic humidity reactions of the beetles Hylobius abietis and Tenebrio molitor
Authors: HAVUKKALA ILKKA
Published: March 2008

ABSTRACT. The effects of spatially uniform but temporally changing air humidity stimuli on the orientation behaviour of the large pine weevil (Hylobius abietis L.) and the flour beetle (Tenebrio molitor L.) were studied in a specially constructed vertical air flow chamber. Moist‐acclimatized but hygronegative pine weevils were exposed for 10 s to a moist air stream (c. 85% R.H.) and then for 10 s to a dry air stream (c. 50% R.H.). The Tenebrio were divided into two groups acclimatized to moist and dry air respectively. For each group the humidity during the initial 5 s in the air stream was the same as during acclimatization, and then changed to the alternative level. In Hylobius the change from moist to dry air caused a decrease in spatial displacement brought about by a decrease in walking speed and an increase in the amount of turning per unit time. In Tenebrio the change from dry to moist air caused a decrease of walking speed and a turning‐back reaction based, presumptively, on idiothetic information about the insect's previous walking direction. The average angle turned during 2 s after the humidity change was 165°. In moist‐adapted beetles the dry air stream caused an identical orthokinetic arrestment, but no klinokinetic or klinotactic reaction. Klinokinesis is redefined as a change in the circular variance of turning angles per unit time, which does not change the mean direction (or directions in cases of multimodal distributions) of the circular distribution. Accordingly, klinotaxis consists of a change in the mean directions) of the circular distribution of angular velocities. In both species the turning frequency was more constant than turning per unit distance, suggesting a temporal control in the nervous system of klinokinetic and klinotactic behaviour.
Acoustic communication between the sexes of the bush cricket, Leptophyes punctatissima
Authors: ROBINSON D. J.
Published: March 2008

ABSTRACT. Both sexes of the speckled bush cricket, Leptophyes punctatissima (Bosc) (Tettigoniidae) produce sound by stridulation. The sound is used in courtship. The male sings for periods throughout the day and night, and there is a peak of activity in the early afternoon. The female sings only in response to a male chirp. The male increases his rate of singing if he receives replies from a female. After 3 days isolation from male song, the female replies most readily to male song mimics of short duration (10 ms) whose carrier frequency is 30 or 45 kHz. Females that have been isolated from male song for 10 days respond less readily than those isolated for 3 days. The short duration of the songs of both sexes reduces their value as locating signals. This disadvantage may be outweighed by the fact that a short signal reduces the chance of a predator detecting the singer by acoustic or visual cues.
Daily patterns of locomotor activity in a wandering spider
Authors: SEYFARTH ERNST‐AUGUST
Published: March 2008

ABSTRACT. Cupiennius salei Keys., a lycosid spider, is night‐active in its natural habitat in the highlands of Guatemala. Locomotor activity begins at dusk after several transitional states, each of which is correlated with a particular light level. Actograph measurements in controlled conditions (LD 12:12 or reversed cycles) show that the spiders begin walking immediately after dark. The activity maximum is reached within the first 3 h of the scotophase (though some spiders displayed additional lights‐on activity in the first hour of the photophase). In DD, Cupiennius shows an endogenous activity rhythm with a mean period of 24.9 h (± 0.31, SE); typically during the first four to six cycles in DD the rhythm ‘splits’ into two components running at different frequencies. In LL (26 1x) the walking activity became arrhythmic. The results are discussed with reference to field and laboratory observations of Cupiennius behaviour and to the consequences for future physiological research with this species.
A technique for studying flight behaviour of tethered Spodoptera exempta moths
Authors: GATEHOUSE A. G. , HACKETT D. S.
Published: March 2008

ABSTRACT. A new apparatus was developed for studies on flight behaviour of the African armyworm, Spodoptera exempta (Wlk.), to record the time and duration of all flights continuously for up to several days. A technique for attaching the mounting bracket to the pharate adult before eclosion allowed flight recording to commence within 1–2h of emergence without the need for anaesthesia. Results obtained using the apparatus indicate that migratory flight does not occur on the night of emergence. The time of take‐off of tethered moths in the laboratory agrees closely with observations of flight behaviour in the field.
Circadian rhythm of proboscis extension responsiveness in the blowfly: central control of threshold changes
Authors: HALL MARTIN J. R.
Published: March 2008

ABSTRACT. The proboscis extension response of the blowfly, Protophormia terraenovae (R.‐D.), elicited by stimulation of the tarsi with sucrose, was studied behaviourally under LD 12:12. A diel rhythm in responsiveness was found that occurred at successively higher daily mean levels as the test flies became increasingly starved. This rhythm persisted for at least one cycle in constant light, demonstrating it to be truly endogenous and circadian. The tarsal chemo‐receptors concerned in initiating the response were examined electrophysiologically in whole fly preparations. No daily change occurred in the response of these receptors to sucrose. Hence central control of the behavioural rhythm of response to sucrose is inferred, and a model is proposed which incorporates a circadian oscillator into the currently accepted model for the control of proboscis extension thresholds.
The role of sex pheromones in initiation of copulatory behaviour by male tsetse flies, Glossina morsitans morsitans
Authors: HUYTON P. M. , LANGLEY P. A. , CARLSON D. A. , COATES T. W.
Published: March 2008

ABSTRACT. Copulatory responses to a variety of decoy objects baited with synthetic 15,19,23‐trimethylheptatriacontane were induced in adult male Glossina morsitans morsitans Westw., provided the object was of similar shape and size to a female fly. Chemical and configurational (shape and texture) stimuli were important in eliciting and maintaining copulatory behaviour of males. A dose/response relationship was obtained from 7‐day‐old test males, with an ED95 of 2 μg using as decoys solvent‐washed dead males baited with 15,19,23‐trimethylheptatriacontane. The quantity of this compound in 5‐day‐old adult females is more than 4.0 μg; in males, only 0.6 μg. It is considered to have the characteristics of a true contact sex pheromone for the species, and does not act synergistically with other less stimulatory synthetic compounds. Gas chromatographic analysis of adult female cuticular paraffins of G.m.morsitans showed the presence of two large peaks between C37 and C38 which were virtually absent in males. Young adults of both sexes possessed a series of hydrocarbons below C29 which disappeared during the first few days of adult life. The natural pheromone appears on the pharate adult female about 2 days before emergence from the puparium and is present throughout life. This suggests it is a component of the surface cuticular waxes. Responsiveness of males to pheromone‐baited decoys increased to a maximum 3–4 days after emergence in regularly fed flies and only declined during the 24 h prior to death from starvation.
Functional involvement of carotenoids in photoperiodic induction of diapause in the spider mite, Tetranychus urticae
Authors: VEERMAN A.
Published: March 2008

ABSTRACT. Using pigment mutants in which the uptake and oxidative metabolism of β‐carotene is disturbed, it could be shown that carotenoid pigments are functionally involved in the photoperiodic reaction in the spider mite, Tetranychus urticae Koch (Acari; Prostigmata). Diapause responses appeared to be lowered in four albino mutants in comparison with the wild‐type strains from which they originated. Back‐crossing of the albino mutants to wild‐type for ten generations did not restore the capability to diapause. Selection for diapause for six generations also proved unsuccessful in increasing the diapause response of the albino strains. On the other hand, albino mites coming from hybrid (phenotypically wild‐type) mothers all diapaused normally. Apparently a maternal effect is responsible for the complete induction of diapause in albino mites. It is supposed that minimal amounts of carotenoids of maternal origin suffice in the embryo for the formation of a photopigment concerned in the photoperiodic induction of diapause. In albino mites the normal transmission of carotenoids via the egg is probably blocked. This transmission of pigment seems to be restored when the albinos originate from hybrid mothers, which possess the wild pigmentation.
An inexpensive electronic device for measuring electroantennogram responses to sex pheromone components with a voltmeter
Authors: BJOSTAD L. B. , ROELOFS W. L.
Published: March 2008

ABSTRACT. An inexpensive, portable device which allows measurement of electroantennogram (EAG) maximum amplitudes with a voltmeter instead of an oscilloscope is described. Potential advantages of the device include more rapid recording, low‐cost construction of additional EAG recording systems for a laboratory with several users, and portability allowing studies in the field and occasional bench top use. The device is intended for use in conventional EAG recording, where EAG signals with rapid depolarizations are being measured, and where the maximum amplitude of the EAG signal is the only parameter of interest.
Reproductive, morphological and behavioural affinities between the alate gynopara and virginopara of the aphid, Aphis fabae
Authors: HARDIE JIM
Published: March 2008

ABSTRACT. ‘Normal’ alate virginoparae reared under long day conditions (LD 16:8) with postnatal crowding, and ‘normal’ gynoparae reared in un‐crowded, short day conditions (LD 12:12) over two generations were compared in respect of the morph of the progeny, the frequency distribution of secondary rhinaria (placoid sensilla) on the third and fourth antennal segments, and preferred larviposition sites. Although in Aphis fabae the two morphs closely resemble one another morphologically, they differed in each of the above characters. Progeny sequences were analysed after transfer to the opposite photoperiodic regime at various times during postnatal development of the alate mothers. Transfer of presumptive gynoparae from short to long days induced the appearance of virginoparous progeny even when the transfer was made just after the final moult. Transfer of presumptive alate virginoparae from long to short days was effective in inducing oviparous offspring, only if the transfer was made during the first instar; oviparae were always first born. Intermediates between oviparae and viviparae were found at the time when the morph of the progeny changed. Transfer from long to short days also induced gynopara production but there appeared to be an intrinsic mechanism which prevented exclusive gynopara production by alates. When first instar, presumptive gynoparae were transferred to long days, the resulting adults would be described both reproductively and behaviourally as alate virginoparae; the opposite switch, of presumptive alate virginoparae to short days, resulted in adult gynoparae on the same criteria. However, the numbers of secondary rhinaria were influenced more by the prenatal than by the postnatal photoperiodic regime. There was an asymmetry of response in that a switch from short to long days had a greater effect on all three characters monitored than did the opposite switch from long to short days.
The effect of ambient temperature on the flight performance of the mature male tsetse fly, Glossina morsitans
Authors: HARGROVE J. W.
Published: March 2008

ABSTRACT. The wingbeat frequency at flight initiation in mature male G.morsitans West, rose approximately linearly from 213 Hz at 20°C to 263 Hz at 32°C. An increase of temperature to 36°C produced no further effect. The time course of frequency changes was affected in a complex manner by temperature, due probably to the interaction of a number of physico‐chemical and behavioural processes with different temperature dependencies. Higher temperatures caused a more rapid overall decline in wingbeat frequency, consistent with the greater demand on the limited reserve of the only important flight substrate, proline. At 20°C, a considerable proportion of tsetse were relatively inactive, whilst a small proportion flew for longer than at any other temperature. At intermediate temperatures both extremes in flight duration decreased, but at 36°C 80% of tsetse flew for less than 90s. These observations can be explained on the basis of the interaction between the tendency of tsetse to be inactive at extremes of temperature, and the more rapid oxidation of reserves at higher temperatures.
Insect photoperiodism — the clock and the counter: a review
Authors: SAUNDERS D. S.
Published: March 2008

ABSTRACT. Insect photoperiodic responses are complex and variable, but all involve a ‘clock’ which is used to determine the qualitative difference between long and short nights, and a ‘counter’ mechanism which accumulates successive long (or short) nights quantitatively up to an internal threshold at which induction (of diapause, seasonal morphs, etc.) is ‘complete’. The clock is circadianbased in at least seven species; in others a non‐oscillatory ‘hour‐glass’ device is indicated, but negative ‘resonance’ experiments may not necessarily rule out a circadian involvement in time measurement. The counter is temperature‐compensated. In some species it adds up long nights, in some short nights, and in others long and short nights. The proportion of the population entering diapause is dependent on an interaction between the temperature‐compensated counter and temperature‐dependent rates of development; this interaction explains many of the known effects of temperature, diet, and latitude in insect photoperiodic responses. In formal terms, the accumulation of long nights is seen as an increase in a ‘diapause titre’ which is compared with an individual internal threshold. In concrete terms, this ‘titre’, and the counter mechanism, might be represented by the accumulation of neurosecretory granules within the neuro‐endocrine system.
Effect on predatory performance of the presence of prey after moulting in the water stick insect, Ranatra linearis
Authors: CLOAREC ANN
Published: March 2008

ABSTRACT. During the first 4h following moulting, Ranatra linearis L. (Heteroptera, Nepidae) perform numerous claw and femur foreleg movements, but do not then catch any prey (e.g. Daphnia). The frequency of these movements depends on the presence of potential prey, and is significantly higher in the presence of potential prey items than in their absence. The presence or absence of prey during these four post‐moult hours influenced subsequent performance. Ranatra moulting in the absence of prey showed later a lower catching success and a smaller proportion of complex predatory movements at all stages of development than did Ranatra moulting in the presence of prey, all other factors being similar. The importance of this deficit resulting from depriving Ranatra of the presence of prey during the post‐moult period is discussed.
Behavioural and electrophysiological responses of the bark beetle, Ips typographus, to potential pheromone components
Authors: DICKENS JOSEPH C.
Published: March 2008

ABSTRACT. Field tests showed (S)‐(‐)‐cis‐verbenol and (R)‐(+)‐trans‐verbenol in combination with a second pheromonal component, 2‐methyl‐3‐buten‐2‐ol, more attractive than the combination with their optical antipodes. Inhibition of response to the attractant component, (S)‐(‐)‐cis‐verbenol, by high concentrations of its optical antipode did not occur. No significant differences were noted for response to the attractant, (S)‐(‐)‐cis‐verbenol and 2‐methyl‐3‐buten‐2‐ol, with the addition of either ipsdienol enantiomer or a racemic mixture of ipsdienol enantiomers. Electroantennogram (EAG) studies correlated well with the behavioural studies. EAGs recorded from male and female beetles revealed both sexes to have a lower threshold for the pheromone, (S)‐(‐)‐cis‐verbenol, than its host terpene precursor, (‐)‐alpha‐pinene. EAGs showed a greater number of acceptors for (‐)‐alpha‐pinene in males than in females. EAGs at acceptor saturation to the enantiomers of alpha‐pinene and the verbenol isomers showed males more responsive to (‐)‐alpha‐pinene, (±)‐cis‐verbenol, and (R)‐(+)‐trans‐verbenol. Significantly greater EAGs were elicited in females than in males to (‐)‐alpha‐pinene, and (±)‐ and (S)‐(‐)‐cis‐verbenol. No significant differences in EAGs of females to the enantiomers of trans‐verbenol were noted. EAGs showed similar thresholds in males and females to the pheromone component, 2‐methyl‐3‐buten‐2‐ol; however, female response at threshold was significantly greater than male response. The results are discussed with regard to olfactory acceptor evolution.
Non‐reproductive determination of ‘migratory’ flight in Argentine stem weevils, Listronotus bonariensis
Authors: GOLDSON S. L.
Published: March 2008

ABSTRACT. The seasonal flight activity of Listronotus bonariensis (Kuschel) between 1976 and 1978 in Canterbury, New Zealand, is described and, in the light of current thinking, interpreted as migratory. Flight intensity appeared to be closely linked to prevailing weather conditions and unrelated to sexual activity. Furthermore, during the summer months a large proportion of flying weevils were gravid, and at the onset of hibernatory diapause flight continued unabated until the occurrence of cold winter conditions. These results indicate none of the energy partitioning often observed in other insect species where reproductive and migratory effort are mutually exclusive.
Three different diel rhythms of the calling song in the cricket, Gryllus campestris, and their control mechanisms*
Authors: HONEGGER HANS‐WILLI
Published: March 2008

ABSTRACT. Males of the cricket, Gryllus campestris L. (Orthoptera: Gryllidae), displayed three different diel patterns in the timing of their calling song: 55% of all males investigated were dark‐active, 25% light‐active and 20% light‐and‐dark‐active. Dark‐active males continued to stridulate in both constant darkness (DD) and constant light (LL) during the subjective night, with a circadian period usually shorter (in DD) or longer (in LL) than 24h. Light‐active males were mainly silent in DD but showed a circadian rhythm in LL, though with a 180° phase shift, i.e. activity during subjective night. This suggests that daytime activity has developed from nocturnal activity by a mechanism which prevents stridulation during darkness, and that both patterns are driven by the same endogenous clock. In the light‐and‐dark‐active males some stridulation takes place during darkness, so dark inhibition is not complete. Such incomplete inhibition seemed to occur only in highly active animals. The three diel distribution patterns of the calling song are discussed in relation to sharing the chances of attracting females.
The flow of food in colonies of the fire ant, Solenopsis invicta: a multifactorial study
Authors: HOWARD DENNIS F. , TSCHINKEL WALTER R.
Published: March 2008

ABSTRACT. A study was conducted to determine the interaction of several factors in the trophallactic distribution of food in colonies of Solenopsis invicta Buren. Radioactive iodine (125I) was used to quantify both the ingestion of test foods by foragers and the distribution of this food to nestmates. A multifactorial design tested the simultaneous effects of: (1) food‐type (sugar water, casein hydrolysate, or oil), (2) temperature during foraging and food‐sharing (25, 30 or 35°C), and (3) starvation period (colonies deprived for 0, 3, 7 or 14 days). The amount of food consumed by foragers was influenced by the interaction of food‐type and starvation. Foragers from severely starved colonies ingested more aqueous foods than did those from slightly starved colonies, but oil was always taken in smaller quantities and its ingestion was least affected by starvation. Ingestion was generally lowest at 35°C, probably because of mutual interference of workers while feeding. Within the colony, food sharing varied with food type and increased with starvation. The sugar solution was utilized primarily by workers. Amino acids were shared throughout the colony, but were directed preferentially to the growing larvae. Soy oil was equally shared among workers and larvae and reached more colony members per initial unit volume than did the other foods. The test factors also interacted in their influence on trophallaxis. Starvation stimulated the dispersal of labelled foods, but at different intensities for different foods. The probability of the queen's receiving food increased when the labelled food was widely exchanged among her nestmates. Casein hydrolysate reached the queen in more cases than did the other tested foods.
A comparison of the behavioural responses of the haematophagous bug, Triatoma infestans, to synthetic homologues of two naturally occurring chemicals (n‐ and iso‐butyric acid)
Authors: WARD J. P.
Published: March 2008

ABSTRACT. Responses of adult Triatoma infestans Klug (Reduviidae) to iso‐butyric acid (which is secreted by the Brindleys glands of this species) and its isomer n‐butyric acid (which is not) were tested in an olfactometer. Bugs avoided both these chemicals with a response that involved klinotactic and orthokinetic components. The avoidance response to iso‐butyric acid showed a marked diminution at high concentrations. Avoidance of n‐butyric acid, however, was inversely proportional to the log of its concentration. This difference in response is discussed in relation to the communicative function of these two chemicals.
Flying and walking of small insects (Musca domestica) recorded differentially with a standing‐wave radar actograph
Authors: BUCHAN PETER B. , MORETON ROGER B.
Published: March 2008

ABSTRACT. An actograph is described for recording the behaviour of small insects, by using a standing‐wave radar system in an enclosed metal cabinet. Experiments show that the system produces an output frequency dependent only on the speed of movement of the subject. By filtering the signal electrically into components below and above 5 Hz, walking and flying of adult Musca domestica could be separately recorded. Each filter is followed by a level‐comparator with hysteresis. Activity causing signal to cross the hysteresis‐band is recorded as an event on a digital counter, and also integrated or summed to be displayed as a stepped‐integral or bar‐chart of total distance covered by the subject in each counting period. The energy‐density of the radar can be kept very low, so that possible influence on the subject is minimal. The detector is remote from the box containing the subject, giving great flexibility in container design, so that the apparatus is ideally suited to the study of environmental factors.
Motor output to the protractor and retractor coxae muscles in stick insects walking on a treadwheel
Authors: GRAHAM D. , WENDLER G.
Published: March 2008

ABSTRACT. The motor output to the protractor and retractor mucles moving the coxa of the middle leg of Carausius morosus was recorded from the thoracic nerves during walking on a treadwheel. The leg movements on the wheel were generally similar to those found in free‐walking animals, but tripod coordination was relatively independent of period, and the coordination of the adult animal on the wheel was most closely related to that found in free‐walking first instars. The activity of a common inhibitor and four excitatory axons of the retractor and an excitatory axon of the protractor were followed for 850 steps (in six animals) to give a summary of the behaviour of the different units. The motor activity is less stereotyped than that previously reported for insects. There was strong reciprocity between the antagonists, but this was not directly correlated with the forward and backward movements of the legs. The first part of the stance phase of the leg was accompanied by a strong burst in the protractor nerve and relatively little retractor activity. This was followed by the main retractor burst which occupied the last 60% of the stance phase. The results are compared with motor output records of the locust and with earlier force‐plate measurements on the stick insect. It must be concluded that the mesothoracic leg initially resists forward movement of the body by the other legs during a typical walking step.
Hormonal influence on feeding and digestion in a plant bug,Dysdercus cingulatus, and a caterpillar,Hyblaea puera
Authors: MURALEEDHARAN D. , PRABHU V. K. K.
Published: March 2008

ABSTRACT.Allatectomy did not affect either food ingestion or midgut protease and invertase activity in adult femaleDysdercus cingulatusFabr., but ingestion of methoprene (juvenile hormone analogue) stimulated food consumption in the late instar caterpillars ofHyblaea pueraCramer. Implantation of brain to raise the insect's own level of brain neurosecretion also stimulated food ingestion inHyblaea.Caterpillars which either ingested methoprene or received brain‐implants showed higher levels of midgut amylase activity. However, no increase in amylase occurred after ingestion of methoprene or implantation of brain followed by starvation. A probable mechanism of hormonal influence on food ingestion and enzyme activity is discussed in the light of these results.
Analysis of zigzagging flight in moths: a correction
Authors: MARSH D. , KENNEDY J. S. , LUDLOW A. R.
Published: March 2008

In 1978 we reported the results of an analysis of the zigzagging behaviour of male Plodia interpunctella flying up a plume of sex pheromone (Marsh et al., 1978). Since then we have discovered that, owing to two technical faults, we used an incorrect time base in analysing the videotape records of the moths' tracks. The original tapes have now been re‐analysed and a full revision paper is being prepared which shows that only one important conclusion must be changed. Meanwhile that incorrect conclusion has been cited at least twice (Schöne, 1980, p.236; Murlis & Jones, 1981) so we here summarize the correction to be made.
Magnetic orientation in the semi‐terrestrial amphipod, Orchestia cavimana, and its interrelationship with photo‐orientation and water loss
Authors: ARENDSE M. C. , BARENDREGT A.
Published: March 2008

ABSTRACT. Orchestia cavimana Heller (Amphipoda, Talitridae) were shown to orient to the geomagnetic field as well as to an anisotropic light field. When tested in an isotropic light field the orientation in the geomagnetic field was either in or opposite to the compass direction of the light vector of the anisotropic light field in which the animals had lived before the test, and this orientation was upset predictably by changing the magnetic field with Helmholtz coils. The polarity of the reaction in both magnetic orientation and photo‐orientation was correlated with pre‐experimental water loss. The magnetic orientation of O. cavimana is compared with that of Tenebrio molitor, and its biological significance discussed.
Sublethal insecticide effects on the probing responsiveness of tsetse flies and blowflies
Authors: CHADD ELIZABETH M. , BRADY JOHN
Published: March 2008

ABSTRACT. Tethered Glossina austeni Newst. males and females were tested for daily and starvation‐related changes in their probing responsiveness to a warmed sponge surface presented to their tarsi. The change in responsiveness of the two sexes was indistinguishable, both following a marked V‐shape pattern across the photophase of LD 12:12 and an increase from a mean of c. 5% responding on day 3 after a blood‐meal to over 60% doing so on day 6. Sublethal doses (c. LD15) of endosulfan had no detectable effect on this pattern, but of DDT caused a temporary doubling of responsiveness, and of permethrin caused a marked and long‐lasting reduction in responsiveness. Tethered Protophormia terraenovae (R.‐D.) tested similarly for changes in threshold to tarsal stimulation with sucrose solutions (assessed by whether or not they extended the proboscis), showed a marked threshold decrease following LD15 diazinon treatment and, like the tsetse, no effect of LD15 endosulfan treatment, though unlike tsetse they showed no increase in threshold following permethrin treatment. The results are discussed in relation to what is known of the mode of action of these four insecticides, and in relation to circadian rhythm physiology in insects.
Experimental analysis of the pattern of tethered flight in the Queensland fruit fly, Dacus tryoni
Authors: CHAPMAN M. G.
Published: March 2008

ABSTRACT. The tethered flight of the Queensland fruit fly, Dacus tryoni Frogg. (Diptera, Tephritidae), was investigated, and the duration of each flight during a 2‐h experimental period was recorded. The pattern of flight was analysed, and related to the age, sex and origin of the specimens, and to the availability of host fruit during the rearing of the adults. The effect of adult crowding on the pattern of flight was also briefly examined. The results indicated that the origin of the flies had little effect on the pattern of flight; male and female flies showed different trends with respect to the proportion of short flights undertaken as the flies matured; and the availability of fruit had a marked effect on the pattern of flight in recently mature flies. These data are discussed with respect to the dispersive/non‐dispersive movements of the flies postulated from previously documented field data. It is suggested that there is a characteristic pattern of tethered flight, which can be related to the absence of hosts in the immediate environment, and would be likely to lead to greater dispersal under natural conditions.
Neurological influences on pheromone release and calling behaviour in the gypsy moth, Lymantria dispar
Authors: HOLLANDER ANDREW L. , YIN CHIH‐MING
Published: March 2008

ABSTRACT. Surgical removal of the brain or disconnection of the last abdominal ganglion from the ventral nerve cord prevented sex pheromone release in female Lymantria dispar (L.) (Lymantriidae), as assayed by the male wing‐fanning response. The calling behaviour continued to occur in individuals whose terminal abdominal ganglion had been thus isolated, however, indicating that the neural mechanisms controlling calling function independently in the last abdominal ganglion.
Respiratory nervous activity in the isolated nerve cord of the larval dragonfly, and location of the respiratory oscillator
Authors: KOMATSU AKIRA
Published: March 2008

ABSTRACT. Rhythmic respiratory nerve activity was recorded in the dragonfly larvae, Anax parthenope Julius Brauer (Anisoptera). Alternating expiratory and inspiratory bursts of spikes occurred in abdominal nerve cords isolated from all peripheral connections. These bursts are similar to the activity recorded in semi‐intact preparations, suggesting that the respiratory rhythm can be generated without peripheral sensory feedback. Expiratory bursts started and ended at the same time in different segments of semi‐intact preparations. When connectives were severed, the nerve cord separated from the last abdominal ganglion did not normally show rhythmic bursts; the last ganglion alone and the nerve cord connected to the last ganglion exhibited the rhythmic bursts. However, in a few cases the nerve cord separated from the last ganglion exhibited the rhythm. The results suggest that the last ganglion contains the main oscillator, but that other weak oscillators occur elsewhere.
Olfactory feedback in the scent marking behaviour of foraging honeybees at the food source?
Authors: PFLUMM WALTER , WILHELM KARL
Published: March 2008

ABSTRACT. Raising or lowering the concentration of Nasonov scent around nectar gathering honeybees (Apis mellifica) had no influence on the following: duration of the scent fanning (‘sterzeln’) before drinking; duration of the sterzeln during drinking; time spent with the scent organ everted during drinking. The presence of citral at the food source also had no effect on any of the above durations. It is concluded that olfactory feedback is not involved in the control of this behaviour.
Visual behaviour of the greenhouse whitefly, Trialeurodes vaporariorum
Authors: COOMBE P. E.
Published: March 2008

ABSTRACT. The behaviour of Trialeurodes vaporariorum (Westwood) (Homoptera, Aleyrodidae) in violet and green light (400 and 550 nm) was examined using several responses. Under 400 nm the whiteflies took‐off more readily and walked faster than under 500 nm. In flight, they oriented towards 400 nm when simultaneously illuminated with equal quanta of 550 and 400 nm light. The ecological significance of this behaviour is discussed, and it is concluded that in nature flying adults would orient towards the sky (i.e. c. 400 nm) but would tend to land on a green plant because plants reflect maximally at 550 nm. Once landed on a suitable food‐plant the position on that plant where the insect finally feeds and reproduces is probably also determined by visual stimuli, since whiteflies will walk to the shaded side of a leaf regardless of whether that is below or above.
Initial diapause and embryonic development in the speckled bush‐cricket, Leptophyes punctatissima
Authors: DEURA K. , HARTLEY J. C.
Published: March 2008

ABSTRACT. The initiation and pattern of embryonic development in Leptophyes punctatissima (Bosc) (Tettigoniidae) are shown to be variously dependent on temperature. Immediate high temperature (30°C) facilitated rapid and direct embryogenesis to the stage of diapause in the fully formed embryo. Slightly lower temperature (25°C) resulted in a delay before embryogenesis started, and this delay was greatly extended as an initial diapause if incubation temperatures were decreased (20‐16°C). Still lower initial temperatures (8–12°C) facilitated subsequent development at 20–30°C. These responses all increased as a function of exposure time. Once initiated, the rate of development was temperature dependent, but competence to tolerate high temperature, and ability to continue development at low temperatures, changed with age. In general, the developmental temperature range appears to be lowered with age. None of these different treatments had any effect on the late embryonic diapause. According to the temperatures prevailing at oviposition, Leptophyes could be an annual or a biennial species; the biennial pattern is normal.
Host's diet effects on nitrogen utilization efficiency for two parasitoid species: Brachymeria intermedia and Coccygomimus turionellae
Authors: GREENBLATT J. A. , BARBOSA P. , MONTGOMERY M. E.
Published: March 2008

ABSTRACT. Differences in the weight of parasitoid individuals of Brachymeria intermedia (Nees) (Chalcidae) and Coccygomimus turionellae (L.) (Ichneumonidae) were found to be associated with differences in host diet. The availability of the host nitrogen to the parasitoids differed depending on the sex of the host, Lymantria dispar, and its diet. Nitrogen utilization efficiency (NUE) for both parasitoid species were inversely correlated with host weight and with host nitrogen. Values for NUE are lower than those reported for phytophagous insects such as Lepidoptera.
Free ecdysteroids in adult male crickets, Gryllus bimaculatus
Authors: HOFFMANN K. H. , BEHRENS W.
Published: March 2008

ABSTRACT. Ecdysteroid titres were determined in testes, fat body, muscles, haemolymph, carcass tissue, spermatophores, and faeces of males of the Mediterranean field cricket, Gryllus bimaculatus de Geer, throughout its adult life span. Considerable amounts of free ecdysteroids are concentrated in the testes and the fat body. The ecdysteroid titres were only slightly influenced by environmental temperature. In all tissues except the fat body, ecdysone and 20‐hydroxyecdysone were the predominant ecdysteroids present. In faeces, highest ecdysteroid concentrations were found at the time of lowest levels in tissues.
Behavioural responses of the carrot fly larva, Psila rosae, to carrot root volatiles
Authors: RYAN M. F. , GUERIN P. M.
Published: March 2008

ABSTRACT. The behaviour of the carrot fly larva, Psila rosae F. (Diptera, Psilidae), was investigated in the presence of six concentrations of thirty‐four volatiles associated with carrot root and of trans‐methyl‐iso‐eugenol, a constituent of carrot herb oil. Bomyl acetate, 2,4‐dimethyl styrene, α‐ionone, SbT‐ionone and biphenyl were the most consistently preferred compounds. Klinotaxis and klinokinesis were the orientation responses near the stimulus source. Trans‐2‐nonenal was the most consistently avoided compound. Extracts derived by steam distillation of carrot roots and by concentration of vapour from roots were resolved, by gas liquid chromatography, into forty‐five and twenty‐two major constituents, respectively. The five preferred compounds are micro‐components of these extracts, collectively representing 1% and 0.6% of root extract oil and vapour, respectively. It is suggested that these secondary plant constituents are specific host finding cues for the larva, and that frara‐2‐nonenal is a carrot defence compound.
Olfactory cues in discrimination among individuals in dominance hierarchies in the cockroach, Nauphoeta cinerea
Authors: SMITH SUSAN K. , BREED MICHAEL D.
Published: March 2008

ABSTRACT. The purpose of this study was to explore the olfactory recognition mechanisms used by individual subordinate male cockroaches, Nauphoeta cinerea (Olivier), in a dominance hierarchy. Results of two independent sets of experiments, one using an olfactometer and the other using an arena, suggest that olfactory cues are important to males. Subordinate males did not avoid dominant male odour in an olfactometer but could discriminate between the odours of familiar and unfamiliar individual dominant males, preferring the odour of the dominant male with which they had previous social contact. Since test subordinates did not avoid dominant male odours in the olfactometer, it is possible that the distance an individual remains from a dominant is important. To test this, individual dominant and subordinate males were tethered in the centre of an arena. Subordinate males were introduced into the arena and allowed to approach the tethered male. They approached tethered dominants and subordinates differently, and tended to keep away from the dominants. Tethered males unfamiliar to the test animals were avoided as well.
Mechanisms of communication disruption by pheromone in the control of Lepidoptera: a review
Authors: CSIRO R. J. BARTELL
Published: March 2008

ABSTRACT. Five possible mechanisms involved in the disruption of phero‐mone‐mediated behaviour in the control of lepidopterous pests are discussed. The various techniques used in the field, laboratory investigations of such mechanisms, and possible limitations in the application of such studies, are reviewed.
Circadian rhythms in the blowfly, Phormia terraenovae: the period in constant light
Authors: ASCHOFF JÜRGEN , PAUL URSULA VON SAINT
Published: March 2008

ABSTRACT. Locomotor activity of individual blowflies, Phormia (=Protophormia) terraenovae R.D. (Diptera, Calliphoridae), was recorded by means of running wheels made of Perspex (plexiglass). At various intervals after hatching, flies were placed in the wheel in continuous light (120 lx). The period of the free‐running rhythm was often shorter than 24 h initially, but lengthened later and stabilized after 15–20 days at values around or above 25 h. The mean period was independent of age in both sexes. Within a range from 2 to 2000lx the period did not depend in a systematic way on intensity of illumination; no activity could be recorded below 1 lx.
Transfer of pheromone from immature queen honeybees, Apis mellifera
Authors: FREE J. B. , FERGUSON A. W.
Published: March 2008

ABSTRACT. Immediately after visiting cells containing immature queens, workers of Apis mellifera L. were observed to engage in prolonged cleaning, particularly of their tongues when they had visited larvae, and of their antennae when they had visited pupae. Thereafter other workers usually initiated and made antennal contacts with them. During such antennal contact the bee that had visited the queen larva often donated food. The implication of these findings on the distribution of pheromone produced by immature queens is discussed. Workers were stimulated to make antennal contact with the excised heads of bees from a queen's court, providing further evidence that queen pheromone is transferred between workers' antennae.
Selection for late pupariation affects diapause incidence and duration in the flesh fly, Sarcophaga bullata
Authors: HENRICH VINCENT C. , DENLINGER DAVID L.
Published: March 2008

ABSTRACT. This artificial selection study with the flesh fly, Sarcophaga bullata Parker, tested the hypothesis that phenotypic variability in the length of the larval stage (under non‐diapause conditions) is largely a consequence of genetic variability. Selection for late pupariation resulted in a line that pupariated significantly later and also developed more slowly during other stages of the life cycle. In a diapause‐inducing environment, the selected line pupariated later, showed a higher incidence of pupal diapause, and remained in diapause longer than the unselected line. This is the first experimental evidence in S.bullata to show that diapause incidence and duration are related. The relationship between developmental rate and diapause traits may stem from the pleiotropic effects of genes associated with late pupariation, or from one or more genes associated with late pupariation being closely linked to genes that affect diapause.
A behavioural gynandromorph of Bombyx mori
Authors: OBARA Y. , TAMAZAWA S.
Published: March 2008

ABSTRACT. The mating behaviour of experimentally produced gynandromorphs of the silkworm moth, Bombyx mori L., were observed. Of 232 gynandromorphs, thirty‐two showed unusual bisexual behaviours. The bisexual behaviours were classified into four behavioural types: ‘dual personality’, ‘schizophrenic’, ‘intersexual’ and ‘sequence‐crossed’. The dual personality gynandromorphs behaved like a male at one time and like a female at another. The schizophrenics displayed male and female behaviours simultaneously in different parts of their body. The intersexuals showed a mixed type of male and female behaviours. The sequence‐crossed animals performed the wrong sexual behaviour (e.g. female) in the context of one sex (e.g. male) when the behaviour of the other sex (i.e. male) would normally have been appropriate. These bisexual behaviours are discussed in terms of sensory and neural mechanisms.
Neural influence on corpus allatum activity and egg maturation in starved virgin Periplaneta americana
Authors: PIPA RUDOLPH L.
Published: March 2008

ABSTRACT. Of sixty‐seven adult female Periplaneta americana (L.) isolated when less than 8h old and kept without food at 25–30°C in LD 12:12, only six produced oothecae during 25–35 days. Growth of the basal oocytes was retarded, and maximal oocyte volume, only one‐third of that in fed virgins, was achieved after about 12 days. By day 14, 60% of the basal oocytes were being resorbed in the starved females, and corpora lutea were usually all that remained beyond day 20. Oocyte growth was potentiated in starved, virgin females by severing either of the two nervi corporis allati 1 (NCA 1), and oothecae were then produced in 45–80% of cases. Sham‐operated controls oviposited in fewer than 27% of the trials. Because oocyte maturation was prevented by extirpating both corpora allata (CA), but not when the glands were replaced, and because the juvenile hormone analogue, ZR 515, was highly effective in causing the starved cockroaches to produce oothecae, the starvation‐induced reproductive failure probably reflects diminished hormone production by the CA. The most likely consequence of severing NCA 1 is de‐repression of juvenile hormone production. The directness of the neural influence was shown by removing the one denervated CA, in which case stimulation of oogenesis was minimal even though the contralateral innervated gland was present. The incidence of ootheca production was not enhanced by transecting the NCA 2, which suggests that the CA of starved cockroaches are not inhibited via this pathway.
Repeated copulation and testes enlargement in Macrotermes michaelseni
Authors: SIEBER R. , LEUTHOLD R. H.
Published: March 2008

ABSTRACT. The minimal copulation frequency of the reproductives of Macrotermes michaelseni (Sjöstedt) was investigated by removing the king from incipient laboratory colonies and from mature field colonies. Laboratory females stopped producing fertile eggs 56–154 days, and physogastric queens from field colonies less than 13 days after the removal of the king. Compared with young laboratory male reproductives, kings from mature field colonies are reported to have enormously enlarged testes, larger corpora allata (CA) and a higher juvenile hormone (JH) titre. However, JH application to young males did not increase the volume of the testes. The testes volumes only increased if the males were kept with additional workers or if their incipient colonies were allowed to grow continuously under unrestricted space conditions. These males also had bigger CA, and the soil in their midgut was replaced by food from the workers. It is concluded that in a growing colony the king is differently fed by the increasing number of workers and that trophic change in combination with higher CA activity induce enlargement of the testes. These enlarged testes are able to produce the sperm to fertilize the large number of eggs laid by a physogastric queen.
Environmental and genetic control of the larval diapause of the Southwestern corn borer, Diatraea grandiosella
Authors: TAKEDA M. , CHIPPENDALE G. M.
Published: March 2008

ABSTRACT. The interaction of photoperiod and temperature in the regulation of the induction and termination of the larval diapause of the Southwestern corn borer, Diatraea grandiosella Dyar (Lepidoptera), was examined. A population originating from south‐eastern Missouri had critical daylengths for diapause induction of about 15h 5min (ecological threshold) and llh (physiological threshold). The ecological threshold was more stable than was the physiological threshold at temperatures lower than 25°C. Above 25°C the diapause response was suppressed. The insect appears to measure photoperiods in a stationary manner since a stepwise increase or decrease in photoperiod did not affect the incidence of diapause. In the critical region of the photoperiodic response curve, a higher incidence of diapause was found among females than among males. Females entered diapause later than did males, but resumed active development earlier than males. The rate of diapause development was more temperature dependent than was the rate of diapause induction, yet it was also clearly under photoperiodic control. The temperature coefficient (Q10) for this process was about 4. Several other factors including sex‐linkage, age, and geographic adaptations are involved in controlling the rate of diapause development, even more so than they are in controlling diapause induction. In the laboratory, the intensity of diapause declined gradually without larvae being exposed to non‐diapause inducing conditions. Incubation of field‐collected larvae revealed that their sensitivity to diapause maintaining photoperiods had ended by January. Three generations of selection of a Mississippi population of D. grandiosella at 30°C and LD 12:12 led to the production of an essentially diapause‐free strain and a diapause strain.