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401.
Ventral polarization vision in tabanids: horseflies and deerflies (Diptera: Tabanidae) are attracted to horizontally polarized light 总被引:1,自引:0,他引:1
Adult tabanid flies (horseflies and deerflies) are terrestrial and lay their eggs onto marsh plants near bodies of fresh water
because the larvae develop in water or mud. To know how tabanids locate their host animals, terrestrial rendezvous sites and
egg-laying places would be very useful for control measures against them, because the hematophagous females are primary/secondary
vectors of some severe animal/human diseases/parasites. Thus, in choice experiments performed in the field we studied the
behavior of tabanids governed by linearly polarized light. We present here evidence for positive polarotaxis, i.e., attraction
to horizontally polarized light stimulating the ventral eye region, in both males and females of 27 tabanid species. The novelty
of our findings is that positive polarotaxis has been described earlier only in connection with the water detection of some
aquatic insects ovipositing directly into water. A further particularity of our discovery is that in the order Diptera and
among blood-sucking insects the studied tabanids are the first known species possessing ventral polarization vision and definite
polarization-sensitive behavior with known functions. The polarotaxis in tabanid flies makes it possible to develop new optically
luring traps being more efficient than the existing ones based on the attraction of tabanids by the intensity and/or color
of reflected light. 相似文献
402.
The plant surface is the substrate upon which herbivorous insects and natural enemies meet and thus represents the stage for
interactions between the three trophic levels. Plant surfaces are covered by an epicuticular wax layer which is highly variable
depending on species, cultivar or plant part. Differences in wax chemistry may modulate ecological interactions. We explored
whether caterpillars of Spodoptera frugiperda, when walking over a plant surface, leave a chemical trail (kairomones) that can be detected by the parasitoid Cotesia marginiventris. Chemistry and micromorphology of cuticular waxes of two barley eceriferum wax mutants (cer-za.126, cer-yp.949) and wild-type cv. Bonus (wt) were assessed. The plants were then used to investigate potential surface effects on
the detectability of caterpillar kairomones. Here we provide evidence that C. marginiventris responds to chemical footprints of its host. Parasitoids were able to detect the kairomone on wild-type plants and on both
cer mutants but the response to cer-yp.949 (reduced wax, high aldehyde fraction) was less pronounced. Experiments with caterpillar-treated wt and mutant leaves
offered simultaneously, confirmed this observation: no difference in wasp response was found when wt was tested against cer-za.126 (reduced wax, wt-like chemical composition) but wt was significantly more attractive than cer-yp.949. This demonstrates for the first time that the wax layer can modulate the detectability of host kairomones. 相似文献
403.
Asbjørn Aaheim Bård Romstad Håkon Sælen 《Mitigation and Adaptation Strategies for Global Change》2010,15(7):763-778
This paper describes how relatively detailed knowledge about probabilities of natural hazards can be used to make decisions
to develop areas and control the risk within hazard zones. The assessment serves two purposes. First, it shows how information
can support decisions. Second, decision criteria put leads on what information is required. This is helpful to identify unavailable
information. We show by an example from a land-slide prone area in Norway how a relatively reliable estimate of the probability
of slides ends up in a rather uncertain estimate of the risk. Uncertainty about the risk represented by natural hazards imply
great challenges to the development of adaptation policies to meet climate change, but they are required. We develop a simplified
criterion for optimal adaptation, and estimate the added social value required to defend development in hazard prone areas
instead of developing a risk-free alternative. The value is estimated between 0 and 0.40 Euros per Euro invested in the case
area, depending on type of slide, category of asset and other costs that occur in the wake of slides. 相似文献
404.
Gergely Hegyi Eszter Szöllősi Susanne Jenni-Eiermann János Török Marcel Eens László Zsolt Garamszegi 《Die Naturwissenschaften》2010,97(6):567-576
The information content of a sexual signal may predict its importance in a multiple signal system. Many studies have correlated
sexual signal expression with the absolute levels of nutrient reserves. In contrast, the changes of nutrient reserves associated
with signal expression are largely unknown in the wild due to technical limitations although they are important determinants
of signal information content. We compared two visual and eight acoustic sexual traits in male collared flycatchers to see
whether the nutritional correlates of expression predict the role of the signal in sexual selection. We used single point
assays of plasma lipid metabolites to estimate short-term changes in nutritional state in relation to sexual trait expression
during courtship. As a measure of sexual selection, we estimated the relationship with pairing latency after arrival in a
4-year dataset. Males which found a mate rapidly were characterized by large wing and forehead patches, but small song strophe
complexity and small figure repertoire size. Traits more strongly related to pairing latency were also more closely related
to changes in nutrient reserves. This indicates a link between signal role and information content. Small wing patches and,
surprisingly, complex songs seemed to indicate poor phenotypic quality and were apparently disfavoured at mate acquisition
in our population. Future studies of the information content of sexual traits, especially dynamic traits such as song, may
benefit from the use of plasma metabolite profiles as non-invasive indicators of short-term changes in body condition. 相似文献
405.
Joke Muys Bettina Blaumeiser Yves Jacquemyn Claude Bandelier Nathalie Brison Saskia Bulk Patrizia Chiarappa Winnie Courtens Anne De Leener Marjan De Rademaeker Julie Désir Anne Destrée Koenraad Devriendt Annelies Dheedene Annelies Fieuw Erik Fransen Jean-Stéphane Gatot Philip Holmgren Mauricette Jamar Sandra Janssens Kathelijn Keymolen Damien Lederer Björn Menten Marije Meuwissen Benoit Parmentier Bruno Pichon Sonia Rombout Yves Sznajer Ann Van Den Bogaert Kris Van Den Bogaert Olivier Vanakker Joris Vermeesch Katrien Janssens 《黑龙江环境通报》2018,38(13):1120-1128
406.
Kaluzhnaya OV Belikov SI Schröder HC Wiens M Giovine M Krasko A Müller IM Müller WE 《Die Naturwissenschaften》2005,92(3):134-138
In a preceding study it has been reported that the freshwater sponge Lubomirskia baicalensis, living in Lake Baikal (East Siberia), is composed of spicules forming a characteristic pattern which follows radiate accretive growth. Here we report that the spicules are synthesized by the enzyme silicatein, a protein which is related to cathepsin L. The cDNAs for silicatein and the related cathepsin L were isolated and used as probes to show that the mRNA levels of silicatein in the bases of the spicule skeleton of the animals are low, while the mRNA level of cathepsin L in this region exceeds that of the growing zone. This is the first comprehensive study on the importance of the axial filament/silicatein as an essential structural and functional component determining the growth and stability of demosponge spicules.Note: Sequences from Lubomirskia baicalensis have been deposited in the EMBL/GenBank; cDNAs for the putative silicatein (LBSILICA) are deposited under the accession no. AJ786771 and for cathepsin L (LBCATL) under the accession no. AJ786770. 相似文献
407.
408.
Leena Maunula M. Rönnqvist R. Åberg J. Lunden M. Nevas 《Food and environmental virology》2017,9(3):358-359
409.