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1.
Settlement and habitat use by juvenile pike in early winter 总被引:2,自引:0,他引:2
The spatial distribution and social behaviour of young-of-the-year pike Esox lucius was investigated in early winter. Reed beds were selected in the early exploration phase but thereafter, pike congregated in the pool habitat. A significant increase in pool occupancy combined with a decrease in reed bed occupancy and movement indicated settlement within 3 days. There was no evidence of territoriality, which has been reported previously in adult pike: indeed, inter-individual spacing was consistent with social grouping rather than territory defence. The strong preference for reed cover among juveniles reported in other studies that were undertaken during summer was not observed here. Among-individual variation in exploratory behaviour was observed but this was not related to activity levels or habitat use. 相似文献
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《Science activities》2013,50(3):49-56
The implications of Earth's ocean being little explored may not be immediately evident to individuals who are not ocean literate. For this reason, initiatives to improve ocean literacy must articulate compelling reasons for ocean exploration. A lesson plan that addresses this issue has been developed as part of the education and outreach program for the National Oceanic and Atmospheric Administration ship Okeanos Explorer, the only U.S. ship whose sole assignment is to systematically explore our largely unknown ocean for the purposes of discovery and the advancement of knowledge. To reinforce key results of student inquiries into the question of why people explore, the authors present a hands-on manipulative activity that uses student-constructed geometric solids called ocean exploration learning shapes to engage students and enhance group discussions. 相似文献
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目的:探讨腹腔镜下胆道镜经胆囊管行胆道探查取石术(LTCBDE)的可行性以及安全性。方法:124 例胆囊合并胆总管结石
患者,根据手术方式分为LTCBDE 组和腹腔镜胆总管切开取石T管引流术(LCTD组),各62 例,比较两组的手术情况、疗效及安
全性。结果:LTCBDE 的手术时间、术后引流时间、肛门排气时间、术后住院时间及补液量较LCTD 组显著减少(P<0.05);LTCBDE
组并发症发生率及复发率分别为3.23%、1.61%,显著低于LCTD 组的20.97%、11.29%(P<0.05)。结论:LTCBDE 创伤小、患者痛
苦少、术后恢复快、并发症少且复发率低,是治疗胆囊结石合并胆总管结石的一种安全可行的微创治疗手段,值得在临床中推广
应用。 相似文献
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David N. Fisher Adèle James Rolando Rodríguez-Mu?oz Tom Tregenza 《Proceedings. Biological sciences / The Royal Society》2015,282(1809)
Examining the relevance of ‘animal personality’ involves linking consistent among- and within-individual behavioural variation to fitness in the wild. Studies aiming to do this typically assay personality in captivity and rely on the assumption that measures of traits in the laboratory reflect their expression in nature. We examined this rarely tested assumption by comparing laboratory and field measurements of the behaviour of wild field crickets (Gryllus campestris) by continuously monitoring individual behaviour in nature, and repeatedly capturing the same individuals and measuring their behaviour in captivity. We focused on three traits that are frequently examined in personality studies: shyness, activity and exploration. All of them showed repeatability in the laboratory. Laboratory activity and exploration predicted the expression of their equivalent behaviours in the wild, but shyness did not. Traits in the wild were predictably influenced by environmental factors such as temperature and sunlight, but only activity showed appreciable within-individual repeatability. This suggests that some behaviours typically studied as personality traits can be accurately assayed in captivity, but the expression of others may be highly context-specific. Our results highlight the importance of validating the relevance of laboratory behavioural assays to analogous traits measured in the wild. 相似文献
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I?aki Rodríguez-Prieto José Martín Esteban Fernández-Juricic 《Proceedings. Biological sciences / The Royal Society》2011,278(1703):266-273
Little is known about the factors causing variation in behavioural plasticity and the interplay between personality and plasticity. Habituation to predators is a special case of behavioural plasticity. We investigated the direct and indirect effects of boldness, exploration and sociability traits on the habituation ability of Iberian wall lizards, considering exposure and sex effects. Individual boldness was consistent across several non-habituation contexts, but it did not significantly affect habituation. Exploration had a strong direct effect on habituation, with more exploratory individuals being able to habituate faster than less exploratory ones, probably because of their ability to assess risk better. Individual variation in habituation was also affected by sociability, but this was an indirect effect mediated by exposure to the predator. Less social individuals avoided refuges with conspecific cues, increasing exposure to the predator and eventually habituation. Finally, the direct effects of sex (females habituated faster than males) were opposite to its indirect effects through exposure. We conclude that risk assessment, instead of the proactivity–reactivity gradient usually considered in the literature, can affect behavioural plasticity through complex interactions between direct and indirect effects, including exploratory behaviour, degree of exposure to the predator and sex, which represent novel mechanisms generating inter-individual variation in plasticity. 相似文献
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