Ueber die Einwirkung der Becquerel- und der Röntgenstrahlen auf das Auge

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Male Attractiveness Is Influenced by UV Wavelengths in a Newt Species but Not in Its Close Relative

Background: Functional communication in the UV range has been reported in Invertebrates and all major groups of Vertebrates but Amphibians. Although perception in this wavelength range has been shown in a few species, UV signalling has not been demonstrated in this group. One reason may be that in lentic freshwater habitats, litter decomposition generates dissolved organic carbon that absorbs UV radiation and thus hinders its use for visual signalling. We tested the effect of male UV characteristics on female sexual preference in two newt species that experience contrasting levels of UV water transmission when breeding. Methodology/Principal Findings: We analysed water spectral characteristics of a sample of breeding ponds in both species. We quantified male ventral coloration and measured male attractiveness under two lighting conditions (UV present, UV absent) using a no-choice female preference design. UV transmission was higher in Lissotriton vulgaris breeding sites. Male UV patterns also differed between experimental males of the two species. We observed a first common peak around 333 nm, higher in L. vulgaris, and a second peak around 397 nm, more frequent and higher in L. helveticus. Male attractiveness was significantly reduced in L. vulgaris when UV was not available but not in L. helveticus. Male attractiveness depended on the hue of the first UV peak in L. vulgaris. Conclusion/Significance: Our study is the first report of functional UV-based communication in Amphibians. Interestingly

Erwiderung auf Hrn. Röntgen's "Beschreibung des Apparates, mit welchem die Versuche über die electrodynamische Wirkung bewegter Dielectrica ausgeführt wurden"

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Analyse spectrale de la lumière propre émise par des cristaux de bromure de radium

Pas de Résumé disponibl

Einige Versuche über Induction in körperlichen Leitern

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Analyse spectrale de la lumière propre du bromure de radium cristallisé

Pas de Résumé disponibl