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131.
Rachel Vallender Vicki L. Friesen Raleigh J. Robertson 《Behavioral ecology and sociobiology》2007,61(12):1797-1807
We examined two components of reproduction in a population of golden-winged warblers in the initial stages of hybridization
with blue-winged warblers. First, we used genetic analyses of mate choice to determine whether copulations outside the social
pairbond (extra-pair copulations; EPCs) occur in these species and their hybrids. Second, we compared several aspects of reproduction
(pairing success, clutch size, hatching success, fledging success, and loss of paternity) in nests raised by phenotypic golden-winged
warblers to those raised by hybrid individuals. Together, these data provide us with the first quantitative analysis of reproduction
within this hybrid system. Our data suggest several reasons why the level of hybridization between these species is likely
being underestimated. First, many birds in our population showed only subtle phenotypic signs of introgression indicating
that hybrid status can only be determined by close examination. Second, high rates of extra-pair paternity indicate that we
cannot base our estimates of hybridization on pairbond data alone. More than 30% of nestlings were the result of EPCs, occurring
in 55% of all nests. Third, there was no difference in the number of hybrid or “pure” golden-winged warbler males chosen as
social mates, relative to their abundance. Indeed, based on several components of nesting success, it appears as though hybrids
are having as great realized reproductive success as are phenotypic golden-winged warblers in our population. Accordingly,
we argue that hybrid reproductive success and extra-pair fertilizations are likely playing a major role in the ongoing hybridization
between blue-winged and golden-winged warblers. Studies such as this one are important to our understanding of the process
and implications of hybridization, and findings may be applicable to other hybrid zones. 相似文献
132.
Alison M. Muldal J. David Moffatt Raleigh J. Robertson 《Behavioral ecology and sociobiology》1986,19(2):105-114
Summary Nestling feeding by males is less common among birds with polygynous mating systems than in monogamous species, because of the pronounced trade-off between parental behavior and the attraction of additional mates. In this study, however, we found that male red-winged blackbirds (Agelaius phoeniceus) commonly assisted females in feeding nestlings in several Ontario marshes. Male parental care was additional to that provided by females, and it significantly enhanced the fledging success of nests (Table 2). Male redwings did not help to feed all nests on their territories: primary and secondary nests were much more likely to receive male parental care than tertiary and later nests. Contrary to expectation, male parental care was not restricted to the nests of primary females: a greater proportion of secondary than primary nests were assisted (Tables 4a and b). The presence of new females settling on the territory at the same time that a resident female had nestlings, resulted in males deferring parental care until a later brood. This suggests that males trade off the recruitment of females against parental care to an existing brood. Although the number of nestlings fledging from a male's territory was strongly influenced by the number of females in the harem, males could additionally increase their reproductive success by feeding nestlings in one or more nests on their territories (Fig. 2). The reproductive success of females was significantly enhanced by male assistance in feeding nestlings (Table 3). However, those females not receiving male assistance on territories of feeding males did not suffer a significantly reduced reproductive success in comparison to females on territories of non-feeding males (Table 2). Males varied considerably in the quality of brood care given. We therefore suggest that the quality of male parental care may be a factor considered by females in choosing a breeding situation. 相似文献
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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
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Clément Feger Laurent Mermet Bhaskar Vira Prue F.E. Addison Richard Barker Frank Birkin John Burns Stuart Cooper Denis Couvet Thomas Cuckston Gretchen C. Daily Colin Dey Louise Gallagher Rosemary Hails Stephen Jollands Georgina Mace Emily Mckenzie Markus Milne Paolo Quattrone Alexandre Rambaud Shona Russell Marta Santamaria William J. Sutherland 《Conservation biology》2019,33(4):972-975
Article impact statement: New collaborations with accounting research can improve conservation impact of ecosystem-based information systems. 相似文献