摘要:

ABSTRACT.Direct observations on the spontaneous activity and visually‐evoked responses of pregnant female Glossina morsitans morsitans Westw. were made hourly during the photophase over the 4 days around larviposition. Visual stimulation was by a 5d̀‐wide vertical black stripe moving laterally, 4 times min‐1atc.5d̀ s‐1. The numbers of take‐offs and the numbers of females taking off were recorded, both in response to the stimulus and spontaneously in its absence. The visual responsiveness paralled both the day‐to‐day changes and the altered circadian patterns of spontaneous activity reported previously (Brady&Gibson, 1983), being very low for the 48 h before parturition. It did not, however, rise in parallel with the increase in spontaneous activity during the last 3–4 h before parturition, and the proportion of flights oriented towards the moving stripe was also much reduced at that time. The significance of this changing responsiveness to slow movement is discussed, and its potential enhancement of any behavioural avoidance of aerosol, non‐residual insecticide spraying during late

ISSN:0307-6962    

DOI:10.1111/j.1365-3032.1984.tb00690.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

ABSTRACT.Observations of the upwind flight of Glossina pallidipes Austen near a source of host odour show that in the absence of a visual target the insects tend to overshoot the odour source in fast, low flight. There is no sign of the crosswind ‘casting’ flight which characterizes the behaviour of moths under similar circumstances, except that a 180d̀ turn is executed to bring the tsetse flies back to the vicinity of the odour source in downwind flight. This may be followed by a second overshoot and another 180d̀ turn before the insects alight within a metre or so of the source. The results indicate that the orientation of tsetse flies to host odour may involve a step‐wise approach to the odour source, providing an opportunity for assessment of wind direction when the insects are at rest between successive bursts of

ISSN:0307-6962    

DOI:10.1111/j.1365-3032.1984.tb00691.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

ABSTRACT.Diuresis in the newly emerged adult mosquito occurs in two phases, a short initial peak immediately after eclosion and a longer peak in the middle of day 1. The present work lends support to the view that the second phase of diuresis is controlled by a hormone which is either released from the head, or from the thorax under the control of the head, 3–4 h after eclosion. The influence of the head ceases to be effective some 9 h later. The rate of water loss is normally higher in unfed females than in unfed males. Whereas the higher rate of diuresis in females during the two peaks is a function of size, the higher rate in unfed females during the second and third day following eclosion is mostly a result of ovarian activity during this perio

ISSN:0307-6962    

DOI:10.1111/j.1365-3032.1984.tb00692.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

ABSTRACT.When presented with dishes containing a range of ‘foliar’ shapes, the onion fly, Delia antiqua (Meigen), laid the most eggs around narrow (4 mm) vertical cylinders. Response to cylinders diminished when their diameter was increased or decreased, when cylinder height was reduced to less than 2 cm, and when cylinder/substrate angle deviated from 90d̀. Differences in egg numbers on stimulatory and non‐stimulatory forms reflected primarily differences in post‐alighting pre‐ovipositional behaviours. Females alighting on narrow vertical cylinders initiated and completed stem runs rapidly and without interruptions, and frequently went on to probe and oviposit. Females alighting on other shapes, or larger, smaller, or non‐vertical cylinders, either did not initiate or did not complete stem runs, or did not go on to probe after completing a stem run. Such females rarely oviposited. Possible causes of such examining behaviours a

ISSN:0307-6962    

DOI:10.1111/j.1365-3032.1984.tb00693.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

ABSTRACT.Dry‐acclimatized mealworm beetles, Tenebrio molitor L. (Coleoptera: Tenebrionidae), were exposed to a rapid change from dry to moist air in an arena with vertical air flow providing spatially uniform humidity, thus precluding orientation along humidity gradients. Subsequent angles of turn were significantly clustered around 90d̀ and 180d̀, and took the beetles back into the region from which they had come. The possibility of geomagnetic orientation was ruled out experimentally and in the apparent absence of other external directional cues it is concluded that the turn sequences were idiothetically controlled and pre‐programmed. This and other cases of ‘longitudinal’ klinotaxis are discussed in the wider context of kineses and taxes and the currently‐questioned value of these

ISSN:0307-6962    

DOI:10.1111/j.1365-3032.1984.tb00694.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

ABSTRACT.The role of dietary nitrogen in reproductive development was investigated in the female boll weevil, Anthonomus grandis (Boh.)(Coleoptera: Curculionidae). Artificial diets were employed containing 1.7%, 2.6% and 4.0% N. Each diet was labelled with a14C‐amino acid mixture and standardized relative to cpm and N per mg of diet dry weight. Egg production, diet consumption, nitrogen consumption and nitrogen utilization were measured by recovering the cpm in the faeces, ovaries plus eggs and the carcass.Females given the 4% N diet initiated oviposition on day 4 with maximum egg production of 11 eggs/day/female occurring on day 6. Females on the 2.6% N diet also initiated oviposition on day 4, but the time necessary to reach maximum egg production was extended. Egg production by these females eventually equalled the total production of the group on the 4% N diet. This was achieved by consuming more diet per female and dedicating a higher percentage of the absorbed diet to egg formation. With the 1.7% N diet, females showed both a delay and a decrease in total egg production because of reduced feeding and a reduced commitment of consumed nutrients to oöcyte maturation.Switching dietary nitrogen concentrations after the initiation of oviposition resulted in changes in consumption and reproductive allocation within 48

ISSN:0307-6962    

DOI:10.1111/j.1365-3032.1984.tb00695.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

ABSTRACT.Chalicodoma sicula (Rossi) is a megachilid bee that constructs ball‐shaped nests out of mud, which are usually attached to twigs or are built on the face of rocks. The nesting female collects sand from a nearby area while mixing it with secretion from labial glands in the head. Chemical analysis of labial glands by gas chromatography mass spectrometry reveal that the secretion is composed of long chain hydrocarbons, mainly hentriacontene and tritriacontene. Once the nest is completed it is covered entirely with a sand‐labial gland mixture. In this form the nest is rendered hydrophobic and is not destroyed by rain for several ye

ISSN:0307-6962    

DOI:10.1111/j.1365-3032.1984.tb00696.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

ABSTRACT.Freely walking crickets were filmed from above during their visual orientation towards a black stripe. A frame‐by‐frame analysis enabled head and body movements to be recorded. The animals walk in 200ms bouts (runs) separated by pauses of similar duration. During each run, rotations of the body axis are observed and some corrections of the course direction occur between successive runs. Generally, the crickets do not walk straight ahead but slightly sideways. Because no lateral head movements were observed during visually orientated locomotion, retinal scanning results from both rotations of the body axis and translation of the head. While walking, one of the target edges is maintained by the cricket on a relatively limited area of the retina, generally between 10d̀ and 25d̀ laterally. Thus, the cricket often records three pieces of information about each edge: one in the monocular visual field, and two in the binocular visual field. Nevertheless, between two pauses, the images of each edge shift asymmetrically on the retinae. Such movement could prevent receptor adaptation by modulation of the ommatidial excitation, or by stimulation of the neighbouring ommatidia. It is also suggested that antennal movements are influenced by the positions of the visually fixated target

ISSN:0307-6962    

DOI:10.1111/j.1365-3032.1984.tb00697.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

ABSTRACT.This study tested the effect of diet and phase of the feeding cycle on oxygen consumption by fifth‐instar larvae of the cinnabar moth Tyria jacobaeae (L.) (Lepidoptera: Arctiidae). There was no significant variation in respiratory rates among larvae fed different diets, which were floral parts, upper, middle and lower leaves of the host plant tansy ragwort, Senecio jacobaea. The respiratory rates (x̄x± 95% Cl μlO2h‐1) of feeding larvae (279.5 ± 30.9) were higher than those of larvae at rest (179.7 ± 12.2), but were not significantly different from those of larvae in the post‐ingestive phase (272.8 ± 35.8).The respiratory rates of feeding larvae increased linearly with the ingestion rate, such that an additional 21.1 μl O2were consumed for every mg dry mass of plant material ea

ISSN:0307-6962    

DOI:10.1111/j.1365-3032.1984.tb00698.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

ABSTRACT.Diuretic hormone is a peptide neurohormone of as yet unknown chemical structure. Attempts to characterize the locust hormone have concentrated on the storage lobes of the corpora cardiaca as a source of material. Bioassay data now indicates that the occurrence of diuretic activity is more widespread in the locust CNS. Dose‐response curves indicate that the levels of the diuretic factor(s) in the brain, sub‐oesophageal and thoracic ganglia are remarkably similar to those found in the corpora cardiaca; activity was also detected in the abdominal ganglia (1–5) and terminal abdominal ganglion. Reverse‐phase HPLC has confirmed that the diuretic material found in the various parts of the CNS is chemically similar to at least one of the diuretic factors separated from the corpora cardiaca. The significance of the widespread distribution of this peptide hormone is considered.Recent evidence of other workers has indicated the possible structural similarity between vertebrate vasopressin and the diuretic factor in the locust sub‐oesophageal ganglion. Chromatographic criteria have been used to demonstrate that the diuretic hormones isolated in our work are not vasopressin‐like molecules, but are chemically distin

ISSN:0307-6962    

DOI:10.1111/j.1365-3032.1984.tb00699.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY