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There is evidence that ocean warming has effects on the ecology, including recruitment dynamics, of marine organisms. In association with rising mean spring temperatures in the Irish Sea, a time-series of juvenile scallop Pecten maximus density around the Isle of Man showed a significant increasing trend since 1991. Favorable conditions (warmer water and correspondingly greater food availability) during gonad development can increase scallop gamete production. We examined the possibility that ocean warming has directly increased recruitment of exploited P. maximus around the Isle of Man by enhancing gonad development. From 1991–2007, there was a significant positive correlation between scallop recruitment and mean spring (the main period of gonad development) temperature in the year of larval settlement. Detrended (i.e., accounting for a time effect) recruitment data showed a marginally non-significant correlation to temperature. Gonadal somatic index of adult scallops and temperature were positively correlated. These relationships support the hypothesis that greater gamete production associated with ocean warming may be primarily responsible for observed increases in recruitment success and CPUE in a commercially important shellfish stock.  相似文献   
87.
Summary. In the rove beetle Aleochara curtula, a male specific sternal gland is described. Isopropyl (Z9)-hexadecenoate has been identified by GC/MS of surface and sternal gland extracts as a male specific compound. Its emission in the air was demonstrated by closed-loopstripping-analyses. In field experiments, conspecific males and females were attracted by the odor of carrion, caged males from laboratory cultures, and by the synthetic ester. Isopropyl (Z9)-hexadecenoate or live males, combined with fresh carrion attract more beetles than a fresh carcass alone. Isopropyl hexadecanoate as a minor compound was not attractive. The term “aggregation” pheromone and the ecological significance of attracting females to a fresh carcass allowing early copulation and egg-deposition are discussed. Received 20 August 1998; accepted 15 January 1999.  相似文献   
88.
In bird communication, listening individuals may obtain information on the quality and motivation of a male not only from solo-singing, but also from song interactions and listeners base their future decisions in territorial and mating contexts on such public information. Eavesdropping on male interactions may thus have a strong influence on sexual selection. In singing interactions, temporal coordination (e.g. overlapping vs. alternating) of two singers as well as structural interaction patterns (e.g. song type matching or repertoire matching) have been described, but the latter is far less studied. By conducting dual-speaker playback experiments with common nightingales Luscinia megarhynchos, we simulated an interaction where one singer was repeatedly song–type matching his counterpart. Playbacks were broadcast to male and female nightingales, and their approach behaviour and singing responses (in the case of male focals) were analysed. We found that both, males and females, spent more time with the matched bird, whereas males additionally sang more songs towards the matching bird. This can be taken as strong hint that eavesdropping occurs in nightingale communication and that listening to male vocal contests might be an important strategy for both sexes to adjust their behavioural output. With regard to the function of song matching, we assume that song-matching is not an aggressive signal per se in nightingales. We rather conclude that vocal leaders within an interaction, here the matched bird, may elicit stronger responses in conspecifics than vocal followers, here the matching bird.  相似文献   
89.
The Norwegian National Committee for Research Ethics inScience and Technology (NENT), collaborating with The NorwegianFisherman's Association and The Research Council of Norway,started in 1999 a project aiming at an ethical assessment of Norwegian fisheries for the year 2020. The project was to preparethe ground for ethical debate in and of the fishery sector inview of pending important decisions on long term strategies. Thispaper has its focus on the method used for achieving these aims,rather than the substantive results concerning the fisheries. Amethod was developed for this purpose, called the ethicalscenario process. This included the construction of scenarios forthe future of Norwegian fisheries, using an ethical matrix for evaluating strategies, and organizing a ``value workshop' whereparticipants from different stakeholder groups came together todo ethical evaluations. The positive achievements and theshortcomings of this method are discussed in this paper. The useof an ethical matrix was meant to combine a participatory approachwith insights from theoretical ethics. The project revealedinherent tensions between these two objectives. Possible ways ofdealing with this tension are indicated, but in general a goodgrasp of the socio-political context might be the best guardianagainst the possible pitfalls involved in such an approach.  相似文献   
90.
At work, people may experience fatigue and a depletion of mental resources. The subsequent need for recovery is generally assessed employing subjective reports on evaluative statements. In this paper, we explore whether it is possible to assess employees’ recovery needs with a systematic inspection of behaviors. The idea is based on Campbell’s paradigm (Kaiser, Byrka, & Hartig, 2010), which holds that individuals will perform more, and more difficult behaviors to recover from fatigue when their need for recovery is higher.  相似文献   
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