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121.
In studying the effect of employment‐relationship practices on employees, research has largely ignored individual differences, both cross‐culturally and within cultures. In this study, the authors examine the moderating effect of middle managers' traditionality, a within‐culture value orientation regarding submission to authority and endorsement of hierarchical role relationships, on their responses to an organization's employee–organization relationship practices. Based on social learning and social exchange theories, the authors expect the more traditional middle managers to respond less positively in terms of their performance and commitment to high levels of expected contributions and the associated psychological empowerment but respond more positively to high levels of offered inducements. Using a sample of 535 middle managers from 40 companies in China, the authors find support for all hypotheses except the moderating effect of traditionality on the relationship between offered inducements and performance. Additional analysis reveals that less‐traditional managers responded to economic rewards (but not developmental rewards) with higher job performance. The paper concludes with a discussion of implications for research and the practice of employment relationships. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
122.
Jan Alexander Häusser Stefan Schulz‐Hardt Thomas Schultze Anne Tomaschek Andreas Mojzisch 《组织行为杂志》2014,35(5):705-721
People frequently have to work in high repetitive jobs. Previous research has focused exclusively on the effects of task repetitiveness on well‐being, while neglecting effects on work performance. In the present study, we aimed to fill this void by conducting two workplace simulations with experimental manipulations of task repetitiveness. Participants worked for about 5 hours at either a computer workstation, compiling computer hardware packages according to customer requests (Experiment 1, N = 160), or at an assembly line, piecing together equipment sets for furniture (Experiment 2, N = 213). Both experiments provide consistent evidence that high repetitiveness has a detrimental effect on well‐being, whereas work performance increases under conditions of high repetitiveness. On a practical level, our study hence shows that high task repetitiveness is a double‐edged sword for both employees and organizations. On a conceptual level, our findings emphasize the necessity to account for both mental strain and work performance when examining the effects of task repetitiveness. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
123.
Anne Marie Power Karen McCrann David McGrath Ruth M. O’ Riordan Christina Simkanin Alan A. Myers 《Marine Biology》2011,158(10):2149-2160
This study examined how the species composition of an intertidal barnacle guild varied according to physical gradients in
the environment at small scales governed by microclimates, medium scales of wave exposure and large scales of latitude. Barnacle
distributions at small and medium scales were sampled in Ireland between 51°29′ and 52°44′N and 6°50′ and 10°08′W. Sampling
on European shores spanned ~18° latitude from 37°05′ to 55°16′N. Barnacle surveys mainly took place in 2003–2004. An index
of wave fetch was calculated along the wave exposure gradient using a digital coastline-based model that was supported by
a biological exposure scale. A ‘dryness’ index was defined according to mean monthly wind speed, fetch along the average wind
direction and mean monthly air or sea surface temperatures for 2 years (January 2001–December 2002) which is the period when
the most recent adults in the barnacle community would have settled and grown to adulthood. The proportion of the dry-loving
barnacle Chthamalus montagui Southward increased within the barnacle guild at all scales as the habitat became warmer and drier. Barnacle densities were
high in all habitats, mean densities ranged from a minimum of 4.16 cm−2 on moderately exposed shores to a maximum of 6.27 cm−2 in sunlit or south-facing microclimates. Percentage cover of barnacles across the gradient of latitudes was usually >70%.
The results suggest that the distribution and abundance of interacting barnacle species on European coasts is strongly controlled
by abiotic factors, most likely temperature and desiccation. 相似文献
124.
Sjouke A. Kingma Michelle L. Hall Anne Peters 《Behavioral ecology and sociobiology》2012,66(8):1115-1123
In passerine birds, storage and maturation of sperm takes place in the cloacal protuberance (CP), an external swelling of the reproductive organ. The considerable variation in CP size among species is presumed to be a consequence of varying levels of sperm-competition, but whether individual variation in CP size within a species also reflects sperm competition is not well established. Here, we study temporal variation in male CP size in relation to within-pair and extra-pair mating opportunities and cuckoldry risk in purple-crowned fairy-wrens Malurus coronatus. This is a socially monogamous cooperatively breeding passerine that can breed year-round and has low levels of extra-pair paternity (in 6?% of broods). We show that male CP size sharply increased a few weeks before, and rapidly regressed after his partner laid eggs, consistent with a cost of its maintenance and/or sperm production. Surprisingly, despite low levels of extra-pair paternity, CP size of non-breeding and pre-breeding males was positively correlated with the number of breeding females in the population, suggesting that CP size is sensitive to extra-pair mating opportunities. However, CP sizes do not seem to reflect cuckoldry risk: CP size of dominant males was unaffected by the presence of a subordinate that was unrelated to the dominant female, although those subordinates occasionally sire offspring, and had a larger CP than subordinates living with their mother. Our results suggest that, even in a species with low levels of extra-pair paternity, individual investment in sperm storage reflects both within-pair and, albeit to lesser extent, extra-pair mating opportunities. 相似文献
125.
Mari B. Abrahamsen Howard I. Browman David M. Fields Anne Berit Skiftesvik 《Marine Biology》2010,157(6):1251-1258
In the north Atlantic, Meganyctiphanes norvegica feeds predominantly on copepods, including Calanus spp. To quantify its perceptual field for prey, and the sensory systems underlying prey detection, the responses of tethered
krill to free-swimming Calanus spp. were observed in 3D using silhouette video imaging. An attack–which occurred despite the krill’s being tethered—was
characterized by a pronounced movement of the krill’s antennae towards the target, followed by a propulsion and opening of
the feeding basket. Frequency distributions of prey detection distances were significantly different in the light vs. the
dark, with median values of 26.5 mm and 19.5 mm, respectively. There were no significant differences in the angles at which
prey were detected by krill (relative to the predator’s longitudinal body axis) in the light vs. the dark. Prey detections
were symmetrically distributed on either side of the predator, in both light and dark. However, significant asymmetry was
found in the dorsal–ventral direction with 80% of the prey detections located below the midline of the krill’s body axis and,
given the placement and orientation of the compound eyes, presumably outside its visual field of view. This indicates that,
at least under these conditions, vision was not the main sensory modality involved in the detection of active prey by M. norvegica. However, under some circumstances, vision may provide supplemental information. Avoidance responses of copepod prey were
nearly twice the velocity of their nominal background swimming speed (153 ± 48 and 85 ± 75 mm s−1, respectively), on average taking them 43 ± 16 mm away from the predator. This is far beyond the krill’s perceptual range,
suggesting that the escape reaction provides an effective deterrent to predation (although perhaps less so for free-swimming
krill). This information can be used to parameterize models that assess the role of krill as predators in marine ecosystems. 相似文献
126.
Silk JB Beehner JC Bergman TJ Crockford C Engh AL Moscovice LR Wittig RM Seyfarth RM Cheney DL 《Behavioral ecology and sociobiology》2010,64(11):1733-1747
Analyses of the pattern of associations, social interactions, coalitions, and aggression among chacma baboons (Papio hamadryas ursinus) in the Okavango Delta of Botswana over a 16-year period indicate that adult females form close, equitable, supportive, and
enduring social relationships. They show strong and stable preferences for close kin, particularly their own mothers and daughters.
Females also form strong attachments to unrelated females who are close to their own age and who are likely to be paternal
half-sisters. Although absolute rates of aggression among kin are as high as rates of aggression among nonkin, females are
more tolerant of close relatives than they are of others with whom they have comparable amounts of contact. These findings
complement previous work which indicates that the strength of social bonds enhances the fitness of females in this population
and support findings about the structure and function of social bonds in other primate groups. 相似文献
127.
Simo Salminen Anne Seppälä 《International journal of occupational safety and ergonomics》2013,19(4):389-397
The aim of this study was to compare assessments made by Finnish- and Swedish-speaking workers in Finland about the safety climate in their companies, because an earlier study showed that the accident frequency of Swedish-speaking workers was one third lower than that of Finnish-speaking workers. 148 Finnish-speaking and 138 Swedish-speaking workers from 14 small and medium-sized companies participated in this study. They filled out a Finnish safety climate questionnaire, the reliability of which was above the acceptable level. There were no differences between the language groups in the total variables of safety climate and safety action. Based on the differences in single items, we interpreted that Swedish-speaking workers stressed collective safety more, whereas Finnish-speaking workers put more emphasis on their personal responsibility for safety. 相似文献
128.
Climate change and associated glacial recession create new stream habitat that leads to the assembly of new riverine communities through primary succession. However, there are still very few studies of the patterns and processes of community assembly during primary succession for stream ecosystems. We illustrate the rapidity with which biotic communities can colonize and establish in recently formed streams by examining Stonefly Creek in Glacier Bay, Alaska (USA), which began to emerge from a remnant glacial ice mass between 1976 and 1979. By 2002, 57 macroinvertebrate and 27 microcrustacea species had become established. Within 10 years of the stream's formation, pink salmon and Dolly Varden charr colonized, followed by other fish species, including juvenile red and silver salmon, Coast Range sculpin, and sticklebacks. Stable-isotope analyses indicate that marine-derived nitrogen from the decay of salmon carcasses was substantially assimilated within the aquatic food web by 2004. The findings from Stonefly Creek are compared with those from a long-term study of a similarly formed but older stream (12 km to the northeast) to examine possible similarities in macroinvertebrate community and biological trait composition between streams at similar stages of development. Macroinvertebrate community assembly appears to have been initially strongly deterministic owing to low water temperature associated with remnant ice masses. In contrast, microcrustacean community assembly appears to have been more stochastic. However, as stream age and water temperature increased, macroinvertebrate colonization was also more stochastic, and taxonomic similarity between Stonefly Creek and a stream at the same stage of development was <50%. However the most abundant taxa were similar, and functional diversity of the two communities was almost identical. Tolerance is suggested as the major mechanism of community assembly. The rapidity with which salmonids and invertebrate communities have become established across an entire watershed has implications for the conservation of biodiversity in freshwater habitats. 相似文献
129.
Senescence, a decrease in life history traits with age, is a within-individual process. The lack of suitable methods to deal with individual heterogeneity has long impeded progress in exploring senescence in wild populations. Analyses of survival senescence are additionally complicated by the often neglected issue of imperfect detectability. To deal with both these issues, we developed state-space models to analyze capture-mark-recapture data while accounting for individual heterogeneity by incorporating random effects. We illustrated our approach by applying it to 29 years of data on breeding females in a Dipper (Cinclus cinclus) population. We highlighted patterns of age-related variation in annual survival by statistical comparisons of piecewise linear, quadratic, Gompertz, and Weibull survival models. The Gompertz model was ranked first in our set. It provided strong evidence for actuarial senescence with an onset of senescence estimated at about 2.3 years. The probability for this model to involve a frailty was 0.15, and the probability to involve an individual latent effect in detection was about 0.4. The estimated mean age at first reproduction was 1.2 years. The general case model described here in detail should encourage the reanalysis of actuarial senescence in cases where imperfect detection or individual heterogeneity is suspected. 相似文献
130.
Neill A. Herbert Jon E. Skjæraasen Trygve Nilsen Anne G. V. Salvanes John F. Steffensen 《Marine Biology》2011,158(4):737-746
The frequency of low O2 (hypoxia) has increased in coastal marine areas but how fish avoid deleterious water masses is not yet clear. To assess whether
the presence and oxygen pressure (PO2) level of an O2 refuge affects the hypoxia avoidance behaviour of fish, individual Atlantic cod (Gadus morhua L.) were exposed to a range of O2 choices in a 2-way choice chamber at 11.4°C over two different experiments. Cod in the first experiment were allowed access
to a fixed O2 refuge (fully air-saturated seawater) whilst oxygen pressure (PO2) on the other side was reduced in steps to a critically low level, i.e. 4.3 kPa—a point where cod can no longer regulate
O2 consumption. Under these conditions, cod did not avoid any level of hypoxia and fish swimming speed also remained unchanged.
In contrast, strong avoidance reactions were exhibited in a second experiment when fish were again exposed to 4.3 kPa but
the safety, i.e. PO2, of the refuge was reduced. Fish not only spent less time at 4.3 kPa as a result of fewer sampling visits but they also swam
at considerably slower speeds. The presence of an avoidance response was thus strongly related to refuge PO2 and it is unlikely that cod, and possibly other fish species, would enter low O2 to feed in the wild if a sufficiently safe O2 refuge was not available. It is therefore hypothesized that the feeding range of fish may be heavily compressed if hypoxia
expands and intensifies in future years. 相似文献