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91.
David F. Westneat Anne B. Clark Katherine C. Rambo D. F. Westneat 《Behavioral ecology and sociobiology》1995,37(5):349-356
We video-taped male and female red-winged blackbirds (Agelaius phoeniceus) feeding individual chicks in order to test the hypothesis that food might be differently allocated to within-pair offspring and extra-pair young. We found no evidence that paternity influenced the allocation of food by either males or females. Both males and females fed male offspring significantly more, but there was no tendency for paternity to be skewed by gender. Females fed older offspring significantly more, whereas males did not; extra-pair fertilizations, however, were not associated with lay or hatch order of the chicks. Given that males do not appear to discriminate within-pair from extra-pair offspring directly, these results are consistent with current theory on the effect of paternity on paternal behavior. We discuss briefly some of the possible reasons why discrimination might be lacking in red-winged blackbirds and in other species in which the possibility of discrimination of paternity and allocation of paternal behavior has been studied. 相似文献
92.
Mark R. L. Forbes Robert G. Clark Patrik J. Weatherhead Terry Armstrong 《Behavioral ecology and sociobiology》1994,34(2):79-85
We tested several predictions of nest defense theory by observing variation in flushing distance and probability of nest abandonment within and between six species of waterfowl. In these species, only the females incubate eggs and attend offspring. First, we examined whether flushing distance by females varied in relation to clutch size, stage of incubation, and time of season, after controlling for the number of visits made to nests by observers. Revisits by observers appeared to affect flushing distance by females for reasons unrelated to the relative value of the current clutch. We found that as incubation progressed, females allowed observers to approach more closely before flushing from the nest. In some species, females with larger clutches allowed closer approaches to nests before flushing which was also consistent with nest defense theory. In contrast, time of season (Julian date) did not relate to flushing distance for any species. When species were compared, we found that species with moderate to high yearly mortality and high reproductive output per breeding attempt (e.g., northern shoveler and blue-winged teal) were less likely to abandon nesting attempts and exhibited riskier behavior (remained at nests when approached closely by observers) than species that had lower yearly mortality (e.g., mallard). Our results show that flushing distance and patterns of nest abandonment by female ducks conform to several predictions of nest defense theory.Correspondence to: M.R.L. Forbes 相似文献
93.
Empathy, a multidimensional construct comprised of cognitive, affective, and behavioral dimensions, has been advanced as a critical predictor of prosocial behavior and effectiveness in the workplace. However, despite organizational interest in empathy, there is a lack of consensus on what empathy is, how empathy should be measured, and how empathy research can meaningfully contribute to our understanding of organizational behavior. This paper aims to provide a roadmap for researchers and practitioners interested in empathy in the workplace. We first provide an updated overview of the state of the broader multidisciplinary literature on empathy. On the basis of this literature, we outline the three dimensions of empathy, discuss the distinctions between state/trait and observer/judged empathy, and compare empathy with related constructs. This integrated multidimensional conceptualization provides the basis for our critical review and recommendations. We review the organizational research on empathy (1983–2018), identifying critical issues with how empathy has been conceptualized, measured, and designed, and offer practical recommendations for the advancement of organizational research on empathy. We conclude by highlighting two fundamental questions: (a) is empathy associated with important outcomes of interest to organizations and employees, and (b) can empathy be changed, and if so, how? 相似文献
94.
Effect of Wastewater Treatment Facility Closure on Endocrine Disrupting Chemicals in a Coastal Plain Stream
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Wastewater treatment facility (WWTF) closures are rare environmental remediation events; offering unique insight into contaminant persistence, long‐term wastewater impacts, and ecosystem recovery processes. The U.S. Geological Survey assessed the fate of select endocrine disrupting chemicals (EDC) in surface water and streambed sediment one year before and one year after closure of a long‐term WWTF located within the Spirit Creek watershed at Fort Gordon, Georgia. Sample sites included a WWTF‐effluent control located upstream from the outfall, three downstream effluent‐impacted sites located between the outfall and Spirit Lake, and one downstream from the lake's outfall. Prior to closure, the 2.2‐km stream segment downstream from the WWTF outfall was characterized by EDC concentrations significantly higher (α = 0.05) than at the control site; indicating substantial downstream transport and limited in‐stream attenuation of EDC, including pharmaceuticals, estrogens, alkylphenol ethoxylate (APE) metabolites, and organophosphate flame retardants (OPFR). Wastewater‐derived pharmaceutical, APE metabolites, and OPFR compounds were also detected in the outflow of Spirit Lake, indicating the potential for EDC transport to aquatic ecosystems downstream of Fort Gordon under effluent discharge conditions. After the WWTF closure, no significant differences in concentrations or numbers of detected EDC compounds were observed between control and downstream locations. The results indicated EDC pseudo‐persistence under preclosure, continuous supply conditions, with rapid attenuation following WWTF closure. Low concentrations of EDC at the control site throughout the study and comparable concentrations in downstream locations after WWTF closure indicated additional, continuing, upstream contaminant sources within the Spirit Creek watershed. ©2016 Wiley Periodicals, Inc. 相似文献
95.
Regional Environmental Change - Climate change and its consequence of sea level rise are major issues for small island developing states (SIDS), as they worsen many other pressures on their people... 相似文献
96.
97.
This study examined the time series pattern of employment growth and stability in Fort Worth, Texas taking into account the March 28, 2000 tornado. The tornado is treated econometrically as an intervention and both the mean and conditional variance of employment growth were estimated. Overall, this regional labor market experienced a decline in the employment growth rate following the tornado. Among the sectors that exhibited differences in employment dynamics between the pre- and post-tornado periods, the mining sector experienced a significant increase in employment growth following the tornado while the service andwholesale, retail trade sectors experienced significant declines in employment growth in the post-tornado period. The manufacturing, service, and wholesale, retail trade sectors were characterized by greater stability (i.e., a lower level of employment growth volatility) in the post-tornado period than in the pre-tornado period. Interestingly, in several sectors, no differences in the time series dynamics of employment growth were detected between the pre- and post-tornado periods. These sectors included construction, finance, insurance, real estate, government, and transportation and public utilities. 相似文献
98.
Mean age and length at onset of maturity were estimated for orange roughy (Hoplostethus atlanticus) populations off New Zealand, Namibia, and Great Britain. Significant between-area differences were apparent in both these
parameters. Implications of the between-area differences on stock structure of orange roughy in New Zealand waters are discussed.
A proportional relationship between age at onset of maturity and modal size of fish in the mature population is demonstrated.
This is consistent with later-maturing fish experiencing a longer period at a pre-maturity growth rate that is relatively
faster than the rate of somatic growth after maturity.
Received: 22 December 1997 / Accepted: 5 May 1998 相似文献
99.
100.
To offset the detrimental effects of urbanization on groundwater recharge, stormwater managers are focusing on infiltrating much of the runoff from a site that was generated because of development. For this to be effective, tools are required to predict the potential for contamination resulting from this infiltration for many site conditions, because infiltration should be stressed in areas where the least potential for causing groundwater contamination exists. Factors that influence contamination potential include the pollutant concentration in the runoff directed to the infiltration device and the ability of the underlying soil to remove the pollutant. The groundwater contamination potential of some pollutants, even those with high concentrations and moderate-to-high mobilities, can be reduced with proper pretreatment before infiltration. This paper presents a methodology that can be used to evaluate infiltration as an management option and introduces two different levels of models that could be used to evaluate contamination potential. 相似文献