Locusts can learn associations between olfactory stimuli and food rewards, and use the acquired memories to choose between foods according to their nutrient requirements. They are a model system for both the study of olfactory coding and insect nutritional regulation. Previous studies have used operant paradigms for conditioning freely moving locusts, restricting the study of the neural mechani...

This thesis is a study of the odour responses of insect olfactory (or odorant) receptor neurons (ORN) of blowfly (Calliphora vicina), mosquito (Aedes communis), fruitflies (Drosophila melanogaster and D. virilis) and large pine weevil (Hylobius abietis). A power-law dependence (similar to Stevens' law in psychophysics) was obtained for the action potential rate of ORN responses vs. odour concen...

Several studies have found body and facial symmetry as well as attractiveness to be human mate choice criteria. These characteristics are presumed to signal developmental stability. Human body odour has been shown to influence female mate choice depending on the immune system, but the question of whether smell could signal general mate quality, as do other cues, was not addressed in previous st...

The air in floor housing systems for laying hens may be more polluted than in traditional cage systems since gases are emitted from large exposed surfaces of manure and litter. In order to study odour and ammonia concentrations and emissions at different climatic conditions a small scale poultry house (climate chamber) was equipped with a floor housing system were 356 laying hens were kept. Tem...

BACKGROUND The mushroom bodies of the insect brain play an important role in olfactory processing, associative learning and memory. The mushroom bodies show odor-specific spatial patterns of activity and are also influenced by visual stimuli. METHODOLOGY/PRINCIPAL FINDINGS Functional imaging was used to investigate changes in the in vivo responses of the mushroom body of the hawkmoth Manduca ...

Secretion of saliva to aid swallowing and digestion is a basic physiological function found in many vertebrates and invertebrates. For mammals, classical conditioning of salivation in dogs was reported by Pavlov a century ago. However, conditioning of salivation or of related neural activities in non-mammalian species has not been reported. In many species of insects, salivation is regulated by...

The epidemiological role of and control options for any mosquito species depend on its degree of 'anthropophily'. However, the behavioural basis of this term is poorly understood. Accordingly, studies in Zimbabwe quantified the effects of natural odours from cattle and humans, and synthetic components of these odours, on the attraction, entry and landing responses of Anopheles arabiensis Giles ...

We tested whether Drosophila larvae can associate odours with a mechanosensory disturbance as a punishment, using substrate vibration conveyed by a loudspeaker (buzz:). One odour (A) was presented with the buzz, while another odour (B) was presented without the buzz (A/B training). Then, animals were offered the choice between A and B. After reciprocal training (A/B), a second experimental grou...

Biofiltration is an inexpensive method of odour removal in which a contaminated air stream is passed through a moist, porous medium before being vented to the atmosphere. Contaminants are absorbed onto the surface of the medium and degraded by microorganisms. Using an air model, the odour reduction resulting from the use of a vertical, lab-scale biofilter in treating off-gases intermittently re...

In a recent PET study on processing of unfamiliar odours we observed that odour discrimination performance was superior during right compared with left nostril presentations, and that mainly the right cerebral hemisphere was activated. In the present study we investigated whether the asymmetric performance is present also during the processing of familiar odours. Seventy-one right-handed health...