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61.
62.
Julien H. Richard Kevin S. White Steeve D. Côté 《Behavioral ecology and sociobiology》2014,68(10):1639-1648
In ungulates, the rut generally leads to increased intra and interpopulation movements for males. Because movements induce energetic costs and missed feeding opportunities, they could be an indication of male mating effort. We studied space use of 44 male mountain goats (Oreamnos americanus) from three neighboring subpopulations in southeast Alaska, during the rut from 2005 to 2008. Using mixed models and an information theoretic approach with AIC, we analyzed the relationships between individual traits of males and their space use. We found no indication of breeding migration between subpopulations. Distances between individual seasonal ranges were not related to any individual trait. Daily movements, home range sizes, and total distance traveled during the rut did not vary with mass or age of individuals. As such, effects of individual traits on male space use during the rut appear weak and observed space use patterns do not support any of the main mating effort hypotheses. 相似文献
63.
Paula Méndez-Fernandez Graham J. Pierce Paco Bustamante Tiphaine Chouvelon Marisa Ferreira Angel F. González Alfredo López Fiona L. Read M. Begoña Santos Jérôme Spitz José V. Vingada Florence Caurant 《Marine Biology》2013,160(11):2825-2840
This study aims to assess niche segregation among the five main toothed whales that frequent the NW Iberian Peninsula waters: the common dolphin, the harbour porpoise, the bottlenose dolphin, the striped dolphin and the long-finned pilot whale. We used cadmium (Cd) and stable isotope ratios (δ13C and δ15N) as ecological tracers to assess degree of segregation in diet/trophic level and in foraging habitat, over various time-scales. δ13C values highlighted different habitats, while Cd concentrations highlighted feeding differences between oceanic and neritic species. Moreover, δ15N values suggest different trophic levels of prey targeted within oceanic and neritic species. Hence, results revealed long-term ecological segregation among five toothed whales that coexist in the NWIP and demonstrated the ability of ecological tracers to discriminate ecological niches among closely related species. 相似文献
64.
Kazuyuki Kudô Sumiko Tsujita Koji Tsuchida Wakana Goi Sôichi Yamane Sidnei Mateus Yosiaki Itô Shinya Miyano Ronaldo Zucchi 《Behavioral ecology and sociobiology》2005,58(1):27-35
In social-insect colonies, cooperation among nestmates is generally stabilized by their high genetic similarity. Thus, fitness gained through cooperation drops quickly as the number of reproductive females (queens) increases. In this respect, wasps of the tribe Epiponini have attracted special attention, because the colonies have tens, or even hundreds of queens. It has been empirically or genetically confirmed that relatedness within nestmates can be elevated by a mechanism known as cyclical monogyny, under which new queens are produced only after the number of old queens is reduced to one. Another likely factor that can increase relatedness within nestmates under polygyny is comb partitioning by queens. If queens concentrate their egg laying on one or a subset of the available combs, then workers may be able to rear closer relatives by focusing their work on the comb where they emerged. Using microsatellite markers, we tested the hypotheses of cyclical monogyny and comb partitioning by queens increasing relatedness within nestmates under polygyny in the large-colony epiponine wasp, Polybia paulista. There were no significant differences between relatedness within combs and between combs, and thus we ruled out the possibility that each queen partitions reproduction between combs. However, as cyclical monogyny predicts, a lower effective number of queens contributed to queen production than to worker production. Cyclical monogyny explained well the observed smaller effective number of queens for new queens than that for workers, but failed to explain the stable relatedness values throughout colony cycles.Communicated by L. Keller 相似文献
65.
Over the last decade, adaptive co‐management has been recommended as a policy framework to address complex and uncertain resources management issues. Implementing this theoretical management concept requires the integration of multidisciplinary research and local knowledge. Yet practical protocols to link science, policymaking and societies have yet to be developed. We designed a protocol to produce legitimate, credible and relevant solutions to a regional resources management issue. This is a two‐component protocol. A stakeholder grid categorizes stakeholder representatives in three distinct specialized dialogue arenas: institution representatives, technical experts and local end‐users. An iterative co‐design process then builds on these arenas to assess the institutional legitimacy, technical credibility and empirical relevance dimensions of a common solution initiated by an initial plausible promise. We tested this framework in Réunion to address organic waste management issues at the regional level. The plausible solution explored was the introduction of a recycling industry involved in collecting organic waste and producing and selling organic fertilizers tailored for local crop systems. The protocol application outcomes were consolidated and documented scenarios accepted by all, with knowledge exchange and the broad spread of a stabilized expectation contributing to private initiatives and public policy change. 相似文献
66.
Miagostovich Marize Pereira Rocha Mônica Simões dos Reis Fabiane Bertoni Sampaio Marcelo Santos de Saldanha da Gama Gracie Carrijo Renata Malta Fabio Correia Rodrigues Janaína Genuino Amanda Ribeiro da Silva Assis Matheus Fumian Tulio Machado Barrocas Paulo Rubens Guimarães 《Food and environmental virology》2020,12(2):130-136
Food and Environmental Virology - The availability of drinking water is one of the main determinants of quality of life, disease prevention and the promotion of health. Viruses are important agents... 相似文献
67.
Soil microbial and faunal community responses to bt maize and insecticide in two soils 总被引:2,自引:0,他引:2
Griffiths BS Caul S Thompson J Birch AN Scrimgeour C Cortet J Foggo A Hackett CA Krogh PH 《Journal of environmental quality》2006,35(3):734-741
The effects of maize (Zea mays L.), genetically modified to express the Cry1Ab protein (Bt), and an insecticide on soil microbial and faunal communities were assessed in a glasshouse experiment. Soil for the experiment was taken from field sites where the same maize cultivars were grown to allow comparison between results under glasshouse conditions with those from field trials. Plants were grown in contrasting sandy loam and clay loam soils, half were sprayed with a pyrethroid insecticide (deltamethrin) and soil samples taken at the five-leaf stage, flowering, and maturity. The main effect on all measured parameters was that of soil type and there were no effects of Bt trait or insecticide on plant growth. The Bt trait resulted in more soil nematodes and protozoa (amoebae), whereas insecticide application increased plant Bt concentration and altered nematode community structure. The only significant effects on soil microbial community structure, microarthropods, and larvae of a nontarget root-feeding Dipteran, were due to soil type and plant growth stage. The results indicate that, although there were statistically significant effects of the Bt trait on soil populations, they were small. The relative magnitude of the effect could best be judged by comparison with the insecticide treatment, which was representative of current best practice. The Bt trait had no greater effect than the insecticide treatment. Results from this glasshouse experiment were in broad agreement with conclusions from field experiments using the same plant material grown in the same soils. 相似文献
68.
69.
70.
Masahiko Tanahashi Kôhei Kubota Norihisa Matsushita Katsumi Togashi 《Die Naturwissenschaften》2010,97(3):311-317
Most wood-feeding insects need an association with microbes to utilize wood as food, and some have special organs to store
and convey the microbes. We report here the discovery of the microbe-storage organ (mycangium) in stag beetles (Coleoptera:
Lucanidae), which develop in decayed wood. The mycangium, which was discovered in the abdomen, is present in all adult females
of 22 lucanid species examined in this study, but absent in adult males. By contrast, adult insects of both sexes of selected
Passalidae, Geotrupidae, and Scarabaeidae, which are related to Lucanidae, lacked mycangia similar to those of the lucanid
species. Yeast-like microbes were isolated from the mycangium of five lucanid species. DNA sequence analyses indicate that
the microbes are closely related to the xylose-fermenting yeasts Pichia stipitis, Pichia segobiensis, or Pichia sp. known from the gut of a passalid species. 相似文献