Disruption of the odour-mediated mating behaviour of Plodia interpunctella using high-frequency sound

Indian meal moths, Plodia interpunctella Hubner ( Lepidoptera: Pyralidae), have ears which are sensitive to high-frequency calls produced by echolocating, insectivorous bats. The influence of artificially generated, high-intensity, ultrasound signals (25 kHz, 106 dB SPL at 1 m distance) on different parameters involved in the odour-mediated mating behaviour of this species and its potential use in population control was investigated. All moths flying towards olfactory cues in flight tunnel experiments reacted strongly to a 1 s ultrasound pulse by cessation of flight and falling out of the odour plume. The source contact proportion of both male moths orienting towards the female-produced sex pheromone and of mated female moths orienting towards an oviposition cue was reduced by 40%, compared to unexposed moths. Calling females responded to the sound by retraction of the ovipositor or by falling to the ground. Long-term exposure to repetitive pulses of ultrasound suppressed female calling by up to 27%. Furthermore, mating in plastic tents was disrupted by up to 58% in ultrasound-treated tents using different sound regimens, compared to control tents. The results are discussed in relation to the potential use of ultrasound technology for the population control of pyralid stored product pests

Foraging and mate-finding in the silver Y moth, Autographa gamma (Lepidoptera : Noctuidae) under the risk of predation

Animal foraging and reproductive behaviour is influenced by other simultaneous demands such as predator avoidance. The trade-offs between these demands may depend on sex or mating experience. This study demonstrates that the olfactory-mediated foraging and mate-seeking behaviours in the silver Y moths, Autographa gamma, are affected by auditory cues mimicking their bat predators. Both males and females changed their foraging behaviour under simulated predation risk. Fewer moths reached the odour source following sound stimulation and the time to find the odour source increased by up to 250%. However. there were no significant differences between male and female ability to reach the plant odour source or the duration of the flight towards the source when stimulated with ultrasound. Hence females are not more cautious than males when observed in the same behavioural context. Risk-taking in males was independent of whether they were flying toward a flower odour or sex pheromones having equal attractive value. This indicates that the trade-off between olfactory and acoustic cues is independent the type of odour. Mated females were not as strongly affected by sound as non-mated, indicating that flower odours have a higher adaptive value for mated females, suggesting that some processes following mating experience influence the trade-off between flower odours and simulated bat sounds

Wool textiles and archaeometry: testing reliability of archaeological wool fibre diameter measurements

Characterisations of ancient sheep breeds and wool types and theories about wool fibre processing are integral parts of textile archaeology. The studies build on statistical calculations of measurements of wool fibre diameters and reveal characteristics of the yarns that are attributed to the available raw wool and to the production methods of the time. Different microscope types have been used for data collection. Presently digital images from either scanning electron microscopy (SEM) or transmitted light microscopy (TLM) are the preferred methods. The advantage of SEM is the good depth of field at high magnification, while TLM is simpler to use and more readily available. Several classification systems have been developed to facilitate the interpretation of the results. In this article, the comparability of the results from these two methods and from the use of different magnifications in general is examined based on the analyses of a large number of the Danish prehistoric textiles. The results do not indicate superiority of one microscope type in favour of another. Rather, they reveal differences in the calculations that can be ascribed to the diversity of the fibres in the individual yarns as well as to the methodology and the magnification level

Wool Textiles and Archaeometry: Testing Reliability of Archaeological Wool Fibre Diameter

Characterisations of ancient sheep breeds and wool types as well as theories about wool fibre processing have become integral parts of textile archaeology. The studies are based on statistical calculations of measurements of wool fibre diameters and reveal characteristics of the yarns that can be attributed to the available raw wool and to the production methods of the people creating the textiles. The types of microscopes used for the analyses have varied through the years and presently digital images from either scanning electron microscopy (SEM) or transmitted light microscopy (TLM) are the preferred methods for data collection. The advantage of SEM is the good depth of field at high magnification while TLM is simpler to use and more readily available. Several classification systems have been developed to facilitate the interpretation of the results. In this paper the comparability of the results from these two methods and from the use of different magnifications in general is examined based on the analyses of a large number of the Danish prehistoric textiles. The results do not indicate superiority of one microscope type in favour of another. Rather, they reveal differences in the calculations that can be ascribed to the diversity of the fibres in the individual yarns as well as to the methodology and the magnification level.The research leading to these results was funded by the Danish National Research Foundation’s Centre for Textile Research [DNRF64], the National Museum of Denmark, the European Commission’s Marie Curie Actions under the European Union’s Seventh Framework Programme [FP7-PEOPLE-IEF-2008-236263], and the European Research Council under the European Union’s Seventh Framework Programme [FP/2007-2013-312603]