ALBERT

Description:    The importance of olfaction in birds’ social behavior has long been denied. Avian chemical signaling has thus been relatively unexplored. The black-legged kittiwake provides a particularly appropriate model for investigating this topic. Kittiwakes preferentially mate with genetically dissimilar individuals, but the cues used to assess genetic characteristics remain unknown. As in other vertebrates, their body odors may carry individual and sexual signatures thus potentially reliably signaling individual genetic makeup. Here, we test whether body odors in preen gland secretion and preen down feathers in kittiwakes may provide a sex and an individual signature. Using gas chromatography and mass spectrometry, we found that male and female odors differ quantitatively, suggesting that scent may be one of the multiple cues used by birds to discriminate between sexes. We further detected an individual signature in the volatile and nonvolatile fractions of preen secretion and preen down feathers. These results suggest that kittiwake body odor may function as a signal associated with mate recognition. It further suggests that preen odor might broadcast the genetic makeup of individuals, and could be used in mate choice to assess the genetic compatibility of potential mates. Content Type Journal Article Pages 1-10 DOI 10.1007/s00114-011-0809-9 Authors Sarah Leclaire, CNRS, Université Paul Sabatier, ENFA; UMR5174 EDB (Laboratoire Évolution et Diversité Biologique), 118 route de Narbonne, F-31062 Toulouse, France Thomas Merkling, CNRS, Université Paul Sabatier, ENFA; UMR5174 EDB (Laboratoire Évolution et Diversité Biologique), 118 route de Narbonne, F-31062 Toulouse, France Christine Raynaud, INRA, LCA (Laboratoire de Chimie Agro-industrielle), F-31029 Toulouse, France Géraldine Giacinti, INRA, LCA (Laboratoire de Chimie Agro-industrielle), F-31029 Toulouse, France Jean-Marie Bessière, Ecole Nationale Supérieure de Chimie de Montpellier, 8 rue de l’Ecole Normale, 34296 Montpellier, France Scott A. Hatch, U.S. Geological Survey, Alaska Science Center, 4210 University Drive, Anchorage, AK 99508, USA Étienne Danchin, CNRS, Université Paul Sabatier, ENFA; UMR5174 EDB (Laboratoire Évolution et Diversité Biologique), 118 route de Narbonne, F-31062 Toulouse, France Journal Naturwissenschaften Online ISSN 1432-1904 Print ISSN 0028-1042

Description:    Leg loss is a common phenomenon in spiders, and according to the species 5% to 40% of the adults can present at least one missing leg. There is no possibility of regeneration after adult moult and the animal must manage with its missing appendages until its death. With the loss of one or more legs, female orb-weaving spiders can be penalized twice: firstly, because the legs are necessary for web construction and secondly, the legs are essential for the control of the prey after its interception by the web. During development, spiders may be also penalized because regeneration has energetic costs that take away resources for survival, growth and reproduction. All these consequences should influence negatively the development of the spider and thus its fitness. We investigated the impact of leg loss in the orb-weaving spider, Zygiella x-notata by studying its frequency in a natural population and web building and prey capture behaviours in laboratory. In field populations, 9.5% to 13%, of the adult females presented the loss of one or more legs; the majority of individuals had lost only one leg (in 48% of cases, a first one). Leg loss seems to affect all the adult spiders, as there is no difference of mass between intact spiders and those with missing leg. Data obtained with laboratory-reared spiders, showed that the loss of legs due to the moult is rare (less than 1%). Considering changes in web design, spiders with missing legs decreased their silk investment, increased the distance between spiral turns but did not change the capture surface of the web. Under our laboratory experimental conditions, spiders with one or two lost legs did not present any difference in prey capture efficiency. In laboratory conditions, spiders with lost leg(s) did not show any difference in egg sac production or in longevity (adult lifespan) compared to intact spiders. Content Type Journal Article Pages 1-8 DOI 10.1007/s00114-011-0799-7 Authors Alain Pasquet, Université de Strasbourg, IPHC, DEPE, CNRS UMR7178, 23 rue Becquerel, 67087 Strasbourg, France Mylène Anotaux, Université de Strasbourg, IPHC, DEPE, CNRS UMR7178, 23 rue Becquerel, 67087 Strasbourg, France Raymond Leborgne, Laboratoire: Expression and Evolution des Comportements, Université Henri Poincaré, Nancy-Université, B.P. 239, 54506 Vandoeuvre-Les-Nancy, France Journal Naturwissenschaften Online ISSN 1432-1904 Print ISSN 0028-1042

Description:    Small Auchenorrhyncha use substrate-borne vibrations to communicate. Although this behaviour is well known in adult leafhoppers, so far no studies have been published on nymphs. Here we checked the occurrence of vibrational communication in Scaphoideus titanus (Hemiptera: Cicadellidae) nymphs as a possible explanation of their aggregative distributions on host plants. We studied possible vibratory emissions of isolated and grouped nymphs, as well as their behavioural responses to vibration stimuli that simulated presence of conspecifics, to disturbance noise, white noise and predator spiders. None of our synthetic stimuli or pre-recorded substrate vibrations from nymphs elicited specific vibration responses and only those due to grooming or mechanical contacts of the insect with the leaf were recorded. Thus, S. titanus nymphs showed to not use species-specific vibrations neither for intra- nor interspecific communication and also did not produce alarm vibrations when facing potential predators. We conclude that their aggregative behaviour is independent from a vibrational communication. Content Type Journal Article Pages 1-4 DOI 10.1007/s00114-011-0808-x Authors Julien Chuche, UMR INRA 1065 Santé et Agroécologie du Vignoble, INRA, BP 81, Institut des Sciences de la Vigne et du Vin, 33883 Villenave d’Ornon Cedex, France Denis Thiéry, UMR INRA 1065 Santé et Agroécologie du Vignoble, INRA, BP 81, Institut des Sciences de la Vigne et du Vin, 33883 Villenave d’Ornon Cedex, France Valerio Mazzoni, IASMA Research and Innovative Centre, Fondazione Edmund Mach, Via E. Mach 1, I-38010 SanMichele a/A (TN), Italy Journal Naturwissenschaften Online ISSN 1432-1904 Print ISSN 0028-1042

Description:    Multiple mating by females with different males (polyandry) is difficult to explain in many taxa because it carries significant costs to females, yet benefits are often hard to identify. Polyandry is a derived trait in social insects, the evolutionary origins of which remain unclear. One of several leading hypotheses for its evolution is that it improves division of labour by increasing intra-colonial genetic diversity. Division of labour is a key player in the ecological success of social insects, and in many successful species of ants is based on morphologically distinct castes of workers, each with their own task specialisations. Atta leaf-cutting ants exhibit one of the most extreme and complicated forms of morphologically specialised worker castes and have been reported to be polyandrous but with relatively low mating frequencies (~2.5 on average). Here, we show for the first time that there is a significant genetic influence on worker size in Atta colombica leaf-cutting ants. We also provide the first estimate of the mating frequency of Atta cephalotes (four matings) and, by analysing much higher within-colony sample sizes, find that Atta are more polyandrous than previously thought (approximately six to seven matings). The results show that high polyandry and a genetic influence on worker caste are present in both genera of leaf-cutting ants and add weight to the hypothesis that division of labour is a potential driver of the evolution of polyandry in this clade of ants. Content Type Journal Article Pages 1-7 DOI 10.1007/s00114-011-0810-3 Authors Sophie Elizabeth Frances Evison, Institute of Integrative and Comparative Biology, Faculty of Biological Sciences, University of Leeds, LS2 9JT Leeds, UK William O. H. Hughes, Institute of Integrative and Comparative Biology, Faculty of Biological Sciences, University of Leeds, LS2 9JT Leeds, UK Journal Naturwissenschaften Online ISSN 1432-1904 Print ISSN 0028-1042

Description:    An important aspect of social insect biology lies in the expression of collective foraging strategies developed to exploit food. In ants, four main types of foraging strategies are typically recognized based on the intensity of recruitment and the importance of chemical communication. Here, we describe a new type of foraging strategy, “tandem carrying”, which is also one of the most simple recruitment strategies, observed in the Ponerinae species Pachycondyla chinensis . Within this strategy, workers are directly carried individually and then released on the food resource by a successful scout. We demonstrate that this recruitment is context dependent and based on the type of food discovered and can be quickly adjusted as food quality changes. We did not detect trail marking by tandem-carrying workers. We conclude by discussing the importance of tandem carrying in an evolutionary context relative to other modes of recruitment in foraging and nest emigration. Content Type Journal Article Pages 1-9 DOI 10.1007/s00114-011-0814-z Authors Benoit Guénard, Department of Biology, North Carolina State University, Raleigh, NC 27607, USA Jules Silverman, Department of Entomology, North Carolina State University, Raleigh, NC 27607, USA Journal Naturwissenschaften Online ISSN 1432-1904 Print ISSN 0028-1042

Description:    Pigeons were released at two sites of equal distance from the loft, one within a magnetic anomaly, the other in magnetically quiet terrain, and their tracks were recorded with the help of GPS receivers. A comparison of the beginning of the tracks revealed striking differences: within the anomaly, the initial phase lasted longer, and the distance flown was longer, with the pigeons' headings considerably farther from the home direction. During the following departure phase, the birds were well homeward oriented at the magnetically quiet site, whereas they continued to be disoriented within the anomaly. Comparing the tracks in the anomaly with the underlying magnetic contours shows considerable differences between individuals, without a common pattern emerging. The differences in magnetic intensity along the pigeons' path do not differ from a random distribution of intensity differences around the release site, indicating that the magnetic contours do not directly affect the pigeons' routes. Within the anomaly, pigeons take longer until their flights are oriented, but 5 km from the release point, the birds, still within the anomaly, are also significantly oriented in the home direction. These findings support the assumption that magnetically anomalous conditions initially interfere with the pigeons' navigational processes, with birds showing rather individual responses in their attempts to overcome these problems. Content Type Journal Article Pages 575-581 DOI 10.1007/s00114-011-0802-3 Authors Ingo Schiffner, Fachbereich Biowissenschaften der J.W.Goethe-Universität Frankfurt, Siesmayerstraße 70, 60054 Frankfurt am Main, Germany Patrick Fuhrmann, Fachbereich Biowissenschaften der J.W.Goethe-Universität Frankfurt, Siesmayerstraße 70, 60054 Frankfurt am Main, Germany Roswitha Wiltschko, Fachbereich Biowissenschaften der J.W.Goethe-Universität Frankfurt, Siesmayerstraße 70, 60054 Frankfurt am Main, Germany Journal Naturwissenschaften Online ISSN 1432-1904 Print ISSN 0028-1042 Journal Volume Volume 98 Journal Issue Volume 98, Number 7

Description:    Unpublished field observations in Leucauge argyra , a tropical orb weaver spider, suggest the occurrence of conspicuous mating plugs that could reduce or prevent remating attempts. Otherwise, the sexual behavior of this species remains unknown. The aims of this study were to describe the courtship behavior and copulation in L. argyra and investigate mating plug formation in this species. Fourteen virgin females and 12 plugged females were exposed to up to three males and checked for mating plug formation. Of the 12 virgins that copulated, nine produced plugs (five immediately after copulation), and the five plugged females that copulated produced another mating plug immediately after copulation. We did not detect the transfer of any male substance during copulation but observed a whitish liquid emerging from female genital ducts. Plug formation was positively associated with male twanging during courtship. One virgin and four plugged females cannibalized males. In seven trials with virgins and in three trials with plugged females, the male’s palp adhered to a substance that emerged from female genital ducts and spread on her genital plate. The male had to struggle energetically to free his glued palp; two of these males were cannibalized while trying to release their palps. Females seem to determine copulation duration by altering the timing of mating plug formation and through sexual cannibalism. This is the first case reported of a mating plug as a sticky trap for males. Content Type Journal Article Pages 1-9 DOI 10.1007/s00114-011-0807-y Authors Anita Aisenberg, Laboratorio de Etología, Ecología y Evolución, Instituto de Investigaciones Biológicas Clemente Estable, Av. Italia 3318, CP 11600 Montevideo, Uruguay Gilbert Barrantes, Escuela de Biología, Universidad de Costa Rica, Ciudad Universitaria, San José, Costa Rica Journal Naturwissenschaften Online ISSN 1432-1904 Print ISSN 0028-1042

Description:    In holometabolous insects, pupation site selection behaviour has large consequences for survival. Here, we investigated the combined effects of temperature and parasitism by the parasitoid Asobara tabida on larval pupation behaviour in two of its main Drosophila sp. hosts differing in their climate origin. We found that larvae of Drosophila melanogaster— a species with a (sub)tropical origin—placed at 25°C pupated higher in rearing jars than those placed at 15°C. The opposite pattern was observed for Drosophila subobscura larvae—a species from temperate regions—which pupated lower, i.e. on or near the substrate at 25°C, than those placed at 15°C. When placed at 25°C, parasitized larvae of both species pupated closer to the substrate than unparasitized ones. Moreover, the Drosophila larvae that had been exposed and probably stung by A. tabida , but were not parasitized, pupated lower than the control unparasitized larvae. These results provide new insights of host behaviour manipulation by A. tabida larvae. Content Type Journal Article Pages 1-5 DOI 10.1007/s00114-011-0813-0 Authors Céline Josso, Université de Rennes 1, UMR CNRS 6553 ECOBIO, 263 Avenue du Général Leclerc, CS 74205, 35042 Rennes Cedex, France Joffrey Moiroux, Université de Rennes 1, UMR CNRS 6553 ECOBIO, 263 Avenue du Général Leclerc, CS 74205, 35042 Rennes Cedex, France Philippe Vernon, Université de Rennes 1, UMR CNRS 6553 ECOBIO, 263 Avenue du Général Leclerc, CS 74205, 35042 Rennes Cedex, France Joan van Baaren, Université de Rennes 1, UMR CNRS 6553 ECOBIO, 263 Avenue du Général Leclerc, CS 74205, 35042 Rennes Cedex, France Jacques J. M. van Alphen, Université de Rennes 1, UMR CNRS 6553 ECOBIO, 263 Avenue du Général Leclerc, CS 74205, 35042 Rennes Cedex, France Journal Naturwissenschaften Online ISSN 1432-1904 Print ISSN 0028-1042

Description:    Mollusc communities of previously unexplored Bulgarian fens were studied in order to determine and generalise the patterns of species richness and composition along the mineral richness gradient. The aim was also to compare predictive values of the environment, vegetation and spatial structure. Altogether, 44 mollusc species were recorded at 40 treeless fen sites. Species richness varied from 0 to 18 species per site, and it was positively associated with the mineral gradient and negatively with altitude. However, the best predictor was obtained using plant species composition. All explanatory variables had higher effect on land snails than on the entire mollusc assemblage (including aquatic species). Species richness and abundance were significantly and positively correlated with the species composition turnover; the communities were highly nested, with poor sites having subsets of the fauna found in the richest. The main direction of mollusc species turnover was highly associated with that observed for vegetation, and the main gradient of plant species composition was able to explain nearly 20% of total variation in mollusc data. We found that spatial structure explained by far the highest proportion of independent variation, which reflected the high level of geographical isolation of Bulgarian fens and regional differences independent of any environmental variation. Our results demonstrate (1) the general role of mineral richness gradient for structuring mollusc communities in fens, (2) the pivotal indicator role of plant species composition in predicting species composition of mollusc communities, despite being trophically independent and (3) the effect of isolation and origins of the habitat on species composition: most species have wide geographical distributions within the habitat type, and geographical patterns within Bulgaria may have a stochastic element. Content Type Journal Article Pages 1-11 DOI 10.1007/s00114-011-0816-x Authors Michal Horsák, Department of Botany and Zoology, Masaryk University, Kotlářská 2, 611 37 Brno, Czech Republic Michal Hájek, Department of Botany and Zoology, Masaryk University, Kotlářská 2, 611 37 Brno, Czech Republic Petra Hájková, Department of Botany and Zoology, Masaryk University, Kotlářská 2, 611 37 Brno, Czech Republic Robert Cameron, Department of Animal and Plant Sciences, University of Sheffield, Sheffield, S10 4TN UK Nicole Cernohorsky, Department of Botany and Zoology, Masaryk University, Kotlářská 2, 611 37 Brno, Czech Republic Iva Apostolova, Department of Phytocoenology and Ecology, Institute of Botany, Bulgarian Academy of Sciences, Sofia, Bulgaria Journal Naturwissenschaften Online ISSN 1432-1904 Print ISSN 0028-1042

Description:    A postanal tail is a major synapomorphy of the phylum Chordata, which is composed of three subphyla: Vertebrata, Cephalochordata, and Tunicata (Urochordata). Among tunicates, appendicularians are the only group that retains the tail in the adult, and the adult tail functions in locomotion and feeding in combination with a cellulose-based house structure. Given the phylogenetic position of tunicates, the appendicularian adult tail may possess ancestral features of the chordate tail. We assess the ultrastructural development of the tail epidermis of the appendicularian Oikopleura dioica . The epidermis of the larval tail is enclosed by the larval envelope, which is a thin sheet similar to the outer tunic layer of ascidian larvae. The epidermis of the adult tail seems to bear no tunic-like cellulosic integuments, and the tail fin is a simple folding of the epidermis. Every epidermal cell, except for the triangular cells at the edge of the tail fin, has a conspicuous matrix layer of fibrous content in the apical cytoplasm without enclosing membranes. The epidermis of the larval tail does not have a fibrous matrix layer, suggesting the production of the layer during larval development and metamorphosis. Zonulae adhaerentes firmly bind the epidermal cells of the adult tail to one another, and the dense microfilaments lining the cell borders constitute a mechanical support for the cell membranes. The intracellular matrix, cell junctions, and cytoskeletons probably make the tail epidermis a tough, flexible shell supporting the active beating of the oikopleuran adult tail. Content Type Journal Article Pages 1-9 DOI 10.1007/s00114-011-0815-y Authors Keisuke Nakashima, Marine Genomics Unit, Okinawa Institute of Science and Technology Promotion Corporation, 1919-1 Tancha, Onna, Okinawa 904-0412, Japan Atsuo Nishino, Department of Biological Sciences, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan Euichi Hirose, Department of Chemistry, Biology and Marine Science, Faculty of Science, University of the Ryukyus, 1 Senbaru, Nishihara, Okinawa 903-0213, Japan Journal Naturwissenschaften Online ISSN 1432-1904 Print ISSN 0028-1042