Smith, H. M., Neaves, L. E., & Divljan, A. (2018). Predation on cicadas by an Australian Flying-fox Pteropus poliocephalus based on DNA evidence. Australian Zoologist, in press.
Abstract: Historically, reports of insectivory in family Pteropodidae have largely been anecdotal and thought to be an incidental corollary of flying-foxes feeding on plant products. More recent direct observations of flying-foxes catching and consuming insects, as well as advances in techniques that increase our ability to detect dietary items, suggest that this behaviour may be deliberate and more common than previously thought. Usually, multiple insects are consumed, but it appears that flying-foxes hunt and eat them one at a time. However, we have collected and photographed oral ejecta pellets under trees with high flying-fox activity, some containing evidence of multiple masticated insects. Further genetic analysis proved that these pellets came from Grey-headed Flying-foxes Pteropus poliocephalus. We propose that flying-foxes use an array of insect feeding strategies, most likely in response to variation in insect abundance and activity, as well as abiotic factors such as light and temperature.
|
Hines, C. W., Fang, Y., Chan, V. K. S., Stiller, K. T., Brauner, C. J., & Richards, J. G. (2018). The effect of salinity and photoperiod on thermal tolerance of Atlantic and coho salmon reared from smolt to adult in recirculating aquaculture systems. Comp Biochem Physiol A Mol Integr Physiol, 230, 1–6.
Abstract: Land-based, closed containment salmon aquaculture involves rearing salmon from smolt to adult in recirculating aquaculture systems (RAS). Unlike in open-net pen aquaculture, rearing conditions can be specified in RAS in order to optimize growth and physiological stress tolerance. The environmental conditions that yield optimal stress tolerance in salmon are, however, unknown. To address this knowledge gap, we reared Atlantic (Salmo salar) and coho (Oncorhynchus kisutch) salmon in 7 separate RASs for 400days post-smoltification under 2 photoperiods (24:0 or 12:12, light:dark) and 4 salinities (2.5, 5, 10 or 30ppt.) and assessed the effects of these conditions on thermal tolerance. We found that over the first 120days post-smoltification, rearing coho under a 24:0 photoperiod resulted in a ~2 degrees C lower critical thermal maxima (CTmax) than in coho reared under a 12:12 photoperiod. This photoperiod effect did not persist at 200 and 400days, which was coincident with an overall decrease in CTmax in coho. Finally, Atlantic salmon had a higher CTmax (~28 degrees C) compared to coho (~26 degrees C) at 400days post-smoltification. Overall, these findings are important for the future implications of RAS and for the aquaculture industry to help identify physiologically sensitive time stages.
|
Stafstrom, J. A., & Hebets, E. A. (2018). Male attraction to female airborne cues by the net-casting spider, Deinopis spinosa. Behav Processes, 159, 23–30.
Abstract: For many animals, finding a mate can be a difficult task. For males, it often involves actively searching for conspecific females, sometimes over great distances. This mate-searching can be aided through chemical or visual signals or cues produced by sexually receptive females. Here, we investigate the roles of olfaction and vision in mate-searching in a strictly nocturnal net-casting spider, Deinopis spinosa. First, we used an olfactometer assay to determine if mature male D. spinosa respond to conspecific airborne cues. We found that mature males, but not mature females, were attracted to airborne cues of mature female conspecifics. We next investigated the relative importance of olfaction and vision in male mate-searching. While manipulating airflow and light levels in screened enclosures in the laboratory, we tested freely moving mature males for mate-searching success. We found no effect of our airflow treatment on mate-searching success. Light levels, however, affected mate-searching in an unexpected way – males were more likely to locate females in complete darkness when compared to dim-light conditions. Our results suggest that visual cues are not necessary for successful male mate-searching in D. spinosa, but that the visual environment can nonetheless influence male behavior. In summary, we provide evidence suggesting that airborne cues, but not visual cues, are important in D. spinosa male mate-searching efforts, though the source of these chemical airborne cues remains unknown.
|
Abbott, S. M., Malkani, R. G., & Zee, P. C. (2018). Circadian disruption and human health: A bidirectional relationship. Eur J Neurosci, in press.
Abstract: Circadian rhythm disorders have been classically associated with disorders of abnormal timing of the sleep-wake cycle, however circadian dysfunction can play a role in a wide range of pathology, ranging from the increased risk for cardiometabolic disease and malignancy in shift workers, prompting the need for a new field focused on the larger concept of circadian medicine. The relationship between circadian disruption and human health is bidirectional, with changes in circadian amplitude often preceding the classical symptoms of neurodegenerative disorders. As our understanding of the importance of circadian dysfunction in disease grows, we need to develop better clinical techniques for identifying circadian rhythms and also develop circadian based strategies for disease management. Overall this review highlights the need to bring the concept of time to all aspects of medicine, emphasizing circadian medicine as a prime example of both personalized and precision medicine.
|
Fotios, S., Monteiro, A. L., & Uttley, J. (2018). Evaluation of pedestrian reassurance gained by higher illuminances in residential streets using the day–dark approach. Lighting Research & Technology, in press.
Abstract: A field study was conducted to investigate how changes in the illuminance affect pedestrian reassurance when walking after dark in an urban location. The field study was conducted in daytime and after dark in order to employ the day–dark approach to analysis of optimal lighting. The results suggest that minimum illuminance is a better predictor of reassurance than is mean illuminance. For a day–dark difference of 0.5 units on a 6-point response scale, the results suggest a minimum horizontal illuminance of approximately 2.0 lux.
|
