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171.
Wasps robbing food from ants: a frequent behavior? 总被引:1,自引:0,他引:1
Food robbing, or cleptobiosis, has been well documented throughout the animal kingdom. For insects, intrafamilial food robbing
is known among ants, but social wasps (Vespidae; Polistinae) taking food from ants has, to the best of our knowledge, never
been reported. In this paper, we present two cases involving social wasps robbing food from ants associated with myrmecophytes.
(1) Polybioides tabida F. (Ropalidiini) rob pieces of prey from Tetraponera aethiops Smith (Formicidae; Pseudomyrmecinae) specifically associated with Barteria fistulosa Mast. (Passifloraceae). (2) Charterginus spp. (Epiponini) rob food bodies from myrmecophytic Cecropia (Cecropiaceae) exploited by their Azteca mutualists (Formicidae; Dolichoderinae) or by opportunistic ants (that also attack cleptobiotic wasps). We note here that
wasps gather food bodies (1) when ants are not yet active; (2) when ants are active, but avoiding any contact with them by
flying off when attacked; and (3) through the coordinated efforts of two to five wasps, wherein one of them prevents the ants
from leaving their nest, while the other wasps freely gather the food bodies. We suggest that these interactions are more
common than previously thought. 相似文献
172.
介绍华能国际电力股份有限公司丹东电厂现采用的一炉一塔石灰石一石膏湿法脱硫方案.主体工程包括烟气系统和二氧化硫吸收系统,配套脱硫剂制备系统、石膏脱水系统等,设计脱硫效率95%,脱硫保证率为90%以上. 相似文献
173.
《Environmental Communication: A Journal of Nature and Culture》2013,7(2):268-277
This study takes an exploratory look at Twitter content in the USA about the emergency at Japan's Fukushima-Daiichi nuclear power station. In particular, I focus on the concepts of the “atrophy of vigilance” from the risk communication literature and the message functions fulfilled for social media users. Two important results emerge from this analysis. First, Twitter content in the USA reflected a cautious approach, mainly suggesting an informative versus interpretive function and rarely mentioning risk or hazard outright. Second, this informative emphasis on risk dominated the content of tweets in the few days following the emergency but decreased substantially within 2 weeks afterwards; it was then overtaken by an interpretive risk emphasis. In addition, toward the end of this period, tweets were more likely to include hyperlinks to websites of traditional news outlets. Implications for the empirical study of social media and risk communication are discussed. 相似文献
174.
Rita Hargitai Kathryn E. Arnold Márton Herényi József Prechl János Török 《Behavioral ecology and sociobiology》2009,63(6):869-882
Offspring survival can be influenced by resources allocated to eggs, which in turn may be affected by the environmental factors
the mother experiences during egg formation. In this study, we investigated whether experimentally elevated social interactions
and number of neighbouring pairs influence yolk composition of collared flycatchers (Ficedula albicollis). Social challenge was simulated by presentation of a conspecific female. Experimental females spent more time near the cage
and produced eggs with higher androgen concentration, but local breeding density did not affect yolk androgen level. Moreover,
we found that females exposed to more intra-specific interactions and those that bred at higher density produced eggs with
smaller yolk. These females may be more constrained in foraging time due to more frequent social encounters, and there might
be increased competition for food at areas of higher density. In contrast, the present study did not reveal any evidence for
the effect of social environment on yolk antioxidant and immunoglobulin levels. However, we found that yolk lutein and immunoglobulin
concentrations were related to the female’s H/L ratio. Also, yolk lutein and α-tocopherol levels showed a seasonal increase
and were positively related to the female’s plasma carotenoid level. Mothers may incur significant costs by transferring these
compounds into the eggs, thus only females in good physiological condition and those that lay eggs later, when food is probably
more abundant, could allocate higher amounts to the eggs without compromising their defence mechanisms. Our results suggest
that environmental circumstances during egg formation can influence conditions for embryonic development. 相似文献
175.
David B. McDonald 《Behavioral ecology and sociobiology》2009,63(7):1029-1034
I use 10 years of data from a long-term study of lek-mating long-tailed manakins to relate the social network among males
to their spatial and genetic structure. Previously, I showed that the network connectivity of young males predicts their future
success. Here, I ask whether kinship might shape the organization of this “young-boy network”. Not surprisingly, males that
were more socially distant (linked by longer network paths) were affiliated with perch zones (lek arenas) that were further
apart. Relatedness (r) among males within the network decreased as social distance increased, as might be expected under kin selection. Nevertheless,
any role for indirect inclusive fitness benefits is refuted by the slightly negative mean relatedness among males at all social
distances within the network (overall mean r = −0.06). That is, relatedness ranged from slightly negative (−0.04) to more negative (−0.2). In contrast, relatedness in
dyads for which at least one of the males was outside the social network (involving at least one blood-sampled male not documented
to have interacted with other banded males) was slightly above the random expectation (mean r = 0.05). The slight variations around r = 0 among males of different categories likely reflect dispersal dynamics, rather than any influence of kinship on social
organization. Relatedness did not covary with the age difference between males. These results, together with previous results
for lack of relatedness between alpha and beta male partners, refute any role for kin selection in the evolution of cooperative
display in this lek-mating system.
This contribution is part of the special issue “Social Networks: new perspectives” (Guest Editors: J. Krause, D. Lusseau,
and R. James). 相似文献
176.
Stefan Krause Lutz Mattner Richard James Tristan Guttridge Mark J. Corcoran Samuel H. Gruber Jens Krause 《Behavioral ecology and sociobiology》2009,63(7):1089-1096
Analyses of animal social networks derived from group-based associations often rely on randomisation methods developed in
ecology (Manly, Ecology 76:1109–1115, 1995) and made available to the animal behaviour community through implementation of a pair-wise swapping algorithm by Bejder
et al. (Anim Behav 56:719–725, 1998). We report a correctable flaw in this method and point the reader to a wider literature on the subject of null models in
the ecology literature. We illustrate the importance of correcting the method using a toy network and use it to make a preliminary
analysis of a network of associations among eagle rays.
相似文献
Stefan KrauseEmail: |
177.
J. L. Verdolin 《Behavioral ecology and sociobiology》2009,63(6):789-799
Few studies have experimentally tested the resource dispersion hypothesis (RDH). In this study, I tested whether space use
and social organization of Gunnison’s prairie dog responded to changes in the dispersion and abundance of resources. Food
manipulations were carried out during the reproductive and nonreproductive seasons across 2 years. Gunnison’s prairie dog
adults responded to the experiments by decreasing territory size as food became patchier in space and time. Both males and
females modified their home ranges, with no detectable difference between sexes, either prior to or during the experiments.
As food became patchier in space and time, the spatial overlap of adults increased, whereas it decreased as food became more
evenly dispersed. The average size of a group, defined as those individuals occupying the same territory, did not change significantly
as a result of the experiments. Where changes in the composition and size of groups did occur, there was no indication that
such changes were sex specific. Results from this study support critical components of the RDH and strongly suggest that patterns
of space use and social structure in Gunnison’s prairie dogs are the result of individual responses to resource abundance
and distribution. 相似文献
178.
Animal social networks: an introduction 总被引:1,自引:1,他引:0
Network analysis has a long history in the mathematical and social sciences and the aim of this introduction is to provide
a brief overview of the potential that it holds for the study of animal behaviour. One of the most attractive features of
the network paradigm is that it provides a single conceptual framework with which we can study the social organisation of
animals at all levels (individual, dyad, group, population) and for all types of interaction (aggressive, cooperative, sexual
etc.). Graphical tools allow a visual inspection of networks which often helps inspire ideas for testable hypotheses. Network
analysis itself provides a multitude of novel statistical tools that can be used to characterise social patterns in animal
populations. Among the important insights that networks have facilitated is that indirect social connections matter. Interactions
between individuals generate a social environment at the population level which in turn selects for behavioural strategies
at the individual level. A social network is often a perfect means by which to represent heterogeneous relationships in a
population. Probing the biological drivers for these heterogeneities, often as a function of time, forms the basis of many
of the current uses of network analysis in the behavioural sciences. This special issue on social networks brings together
a diverse group of practitioners whose study systems range from social insects over reptiles to birds, cetaceans, ungulates
and primates in order to illustrate the wide-ranging applications of network analysis.
This contribution is part of the special issue “Social Networks: new perspectives” (Guest Editors: J. Krause, D. Lusseau and
R. James). 相似文献
179.
Some policy problems pit one group?s interests against another?s. One group may determine provision of a project (such as a dam) that benefits group members but hurts others. We introduce a model of such projects. In-group members may contribute to a common fund that benefits them as a public good. Benefits from the project may vary within the group. Provision has negative downstream externalities: contributions hurt agents outside the in-group (“Outsiders”), rendering them anti-social. Many models of social preferences predict that such externalities should reduce provision, although conditional cooperation or a preference for in-group members may counteract this. We test this model with a lab experiment using Outsiders with whom the in-group members have more and less contact. With homogeneous in-group benefits, the presence of negative downstream externalities reduces contributions by half when they have closer contact with Outsiders but not at all when they have had no contact. We introduce a rotating high-return position that allows subjects to trade favors. In this setting, contributions of non-privileged members diminish slightly when faced with the negative externality given closer contact with Outsiders, and not at all with less contact. Reciprocal giving occurs whether or not Outsiders are present. 相似文献
180.
An estimate of the social cost of carbon (SCC) is crucial to climate policy. But how should we estimate the SCC? A common approach uses an integrated assessment model (IAM) to simulate time paths for the atmospheric CO2 concentration, its impact on temperature, and resulting reductions in GDP. I have argued that IAMs have deficiencies that make them poorly suited for this job, but what is the alternative? I present an approach to estimating an average SCC, which I argue can be a useful guide for policy. I rely on a survey of experts to elicit opinions regarding (1) probabilities of alternative economic outcomes of climate change, but not the causes of those outcomes; and (2) the reduction in emissions required to avert an extreme outcome, i.e., a large climate-induced reduction in GDP. The average SCC is the ratio of the present value of lost GDP from an extreme outcome to the total emission reduction needed to avert that outcome. I discuss the survey instrument, explain how experts were identified, and present results. I obtain SCC estimates of $200/mt or higher, but the variation across experts is large. Trimming outliers and focusing on experts who expressed a high degree of confidence in their answers yields lower SCCs, $80 to $100/mt, but still well above the IAM-based estimates used by the U.S. government. 相似文献