摘要:

ABSTRACT.The larvae and adults ofBelgica antarcticawere studied in an attempt to identify the mechanism of low temperature adaptation that enables this species to survive in the Antarctic. Larvae are freezing‐tolerant during the austral summer and elaborate a complex of cryoprotectants including erythritol, glucose, sucrose and trehalose. Adults are freezing‐susceptible and lack adequate quantities of cryoprotectants. Maintenance on artificial diets indicated that cryoprotectant profiles have food‐source and temperature‐dependent components. In addition, direct utilization of dietary cryoprotectants is su

ISSN:0307-6962    

DOI:10.1111/j.1365-3032.1979.tb00171.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

摘要:

ABSTRACT.Negative feedback to protein feeding byPhormiais transmitted to the brain via the abdominal nerve. The inhibition is apparently generated by stretch receptors in the abdominal wall. This feedback makes a protein meal self‐limiting, supplying progressively more inhibition as the fly's swelling crop enlarges the abdomen during a meal. Abdominal stretch resulting from a mature egg mass also inhibits protein feeding by gravid females. This stretch seems to terminate protein feeding ‘prematurely’, leaving the female ‘primed’ to consume protein as soon as abdominal stretch is relaxed. The adaptive value of such a mechanism can be envisioned when one notes that the abdominal stretch normally will be relaxed only at a source of proteinaceous material, where the female lays her eggs. This would permit the fly to take advantage of the protein source before she flies away. The amount of protein consumed at such a time would normally be greater than the total amount stored in the fat body, thereby providing an important contribution toward the development of the next batc

ISSN:0307-6962    

DOI:10.1111/j.1365-3032.1979.tb00172.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

摘要:

ABSTRACT.The complex system of alarm communication inOecophylla longinodais described. The mandibular gland secretion of major workers releases in other major workers a complex pattern of behaviour, which includes components of alerting, attraction and biting. The main constituents of the secretion are hexanal and 1‐hexanol, which release alerting and attraction respectively. Of the thirty or so trace components, at least two, 2‐butyl‐2‐octenal and 3‐undecanone, act as markers for attack. In combination, these components produce a sequential message in space and time, dependent on their relative proportions, volatilities and threshold concentrations for behavioural

ISSN:0307-6962    

DOI:10.1111/j.1365-3032.1979.tb00173.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

摘要:

ABSTRACT.Considerable differences were found in the composition of the volatile cephalic chemical of the castes ofOecophylla longinoda.The mandibular glands of minor workers contain a series of primary alcohols, predominantly 1‐hexanol, 1‐octanol and 1‐nonanol, together with nerol and geraniol. Hexanal, 2‐butyl‐2‐octenal and 3‐undecanone (components of the mandibular gland secretion of major workers, and which are important stimuli in alarm communication) are absent. Major workers are attracted and arrested by high concentrations of nerol, which is part of a possible mechanism for communication within the nest. The heads of males contain a pungent secretion, which may be used in defence; the major constituents are five aliphatic acids. The quantities of both main and trace constituents of the mandibular gland secretion of major workers were found to vary between colonies collected in different areas o

ISSN:0307-6962    

DOI:10.1111/j.1365-3032.1979.tb00174.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

摘要:

ABSTRACT.Major workers ofOecophylla longinodaemit venom from the tip of the abdomen, as it is brought immediately above the head. The sources of the venom are (a) the poison gland, which contains formic acid, and (b) Dufour's gland, which contains hydrocarbons, including n‐undecane and other n‐alkanes, 4‐tridecene, 8‐heptadecene and 4, 7‐heptadecadiene. The venom elicits a ‘mass attack’ response in other major workers. Formic acid and n‐undecane presented together experimentally also evoke this response, the mixture being considerably more effective than either compound tested separately. These compounds act in combination with the mandibular gland secretions to form a complex alarm

ISSN:0307-6962    

DOI:10.1111/j.1365-3032.1979.tb00175.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

摘要:

ABSTRACT.In the grasshopperO.viridulus, two song parameters were analysed during post‐larval ontogeny. The impulse rate (i.e. the rate at which the femur pegs strike the forewing vein) shows a modulation during up‐ and downstrokes of the hindleg. During post‐larval development there is no detectable change in characteristic impulse intervals, indicating a constancy of the hindleg‐stroke movement irrespective of age. The impulse frequency spectrum also shows considerable constancy during post‐larval ontogeny. Apparently, the main song features, including the underlying motor pattern, are completed with the early song productions of

ISSN:0307-6962    

DOI:10.1111/j.1365-3032.1979.tb00176.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

摘要:

ABSTRACT.Previous publications have demonstrated thatO.miniataadults exhibit an aestival reproductive diapause during the dry summer in Israel; females do not lay and males show only little mating behaviour. It was also reported previously that photoperiod and temperatures corresponding to autumn in Jerusalem terminate diapause and induce intense male mating behaviour, whereas continuous illumination and high temperatures maintain diapause. In the present study we used mating behaviour as an indicator for investigating the effects of several photoperiod—temperature combinations on reproductive diapause inO.miniatamales. Mating behaviour was induced and diapause terminated under the following conditions: LD 10.5:13.5, T = 38‐27°C (the temperatures during the photophase and scotophase, respectively); LD 12:12, T=38–27°C; LD 12:12, T=26–13°C; LD 14:10, T = 26–13°C. In contrast, diapause was maintained under LD 14:10, T = 38–27°C and under LL with high but variable temperatures. In further experiments males that were already sexually active, and which had been kept under LD 12:12, T = 38–27°C, were transferred to LL with high variable temperatures. Similarly, postdiapause males which had been kept under LD 14:10 and T=26–13°C were transferred to T = 38–27°C without changing the photoperiod. In both instances mating behaviour declined, then disappeared, thus reinduction of the diapause occurred under such conditions which previously were found to maintain diapause.O.miniatais therefore a ‘short day’ and/or ‘low temperature’ insect. This is the first report on complete control of photoperiod—temperature over aestival reproductive diapause and

ISSN:0307-6962    

DOI:10.1111/j.1365-3032.1979.tb00177.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

摘要:

ABSTRACT.The host‐finding sequence ofApanteles glomeratusfemales and the factors involved in it were analysed. A female wasp is attracted by the leaf odour of the food plant of the host (Pieris rapae crucivord). She then walks slowly with the tips of her antennae rubbing the leaf surface. When she comes across damage produced by the host's feeding, her antennae are raised and she turns towards the damage. She often then erects her wings and/or bends her abdomen forward in response to a chemical produced from the leaf by the host's saliva. Long‐lasting searching elicited by this odour normally leads to an encounter with a host caterpillar, whereupon odour from the host itself releases opposition. Host saliva, faeces and silk are also involved in these responses, but the response to fresh leaf damage has the most specific function in the overall strategy of host‐fi

ISSN:0307-6962    

DOI:10.1111/j.1365-3032.1979.tb00178.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

摘要:

ABSTRACT.Mating inDacus tryoniis restricted to dusk, whereas that of a sibling species,Dacus neohumeralis, occurs in the middle of the day. The timing of sexual behaviour in both species is determined by an interaction between a circadian clock and light intensity. InD. tryonipeak mating responsiveness is at the time of dusk, and the optimal light intensity for mating is approximately 91x. InD.neohumeralispeak responsiveness is in the middle of the day, and the optimal light intensity for mating is greater than 10 000 lx. The two species were crossed and the time of mating and response to light intensity of F1, F2and backcross progeny determined. The circadian clock set a mating phase (‘gate’) as narrow in F1flies as in their parents, suggesting the circadian timing mechanism to be common between the two species. The results indicate that the genetic mechanism controlling timing is independent of that controlling response to light intensity, and that both genetic mechanisms are comp

ISSN:0307-6962    

DOI:10.1111/j.1365-3032.1979.tb00179.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

摘要:

ABSTRACT.The effect of allatectomy on synthesis of accessory reproductive gland secretion, spermatophore production and sexual behaviour in maleDiploptera punctatawas investigated during the first 6 weeks of adult life. After allatectomy, synthesis of the secretion and production of spermatophores was slightly reduced relative to sham‐operated animals (by 16%), but not relative to normal animals. However, sexual behaviour of the operated animals appeared normal. Thus, the corpora allata (CA) may not be necessary for the sexual functioning of maleD.punctata.The synthesis of C16juvenile hormone (C16JH; JH III) by isolated pairs of CA from individual males was followed during this period and, at all times, the rate of synthesis was less than 8pmolh‐1per pair, a rate similar to that observed in pregnant females. The significance of this continued synthesis of JH by male CA is unknown, although it may be related to the maintenance of general metabolic activit

ISSN:0307-6962    

DOI:10.1111/j.1365-3032.1979.tb00180.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY