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521.
Dhruba Naug 《Behavioral ecology and sociobiology》2009,63(7):1023-1028
Social interactions are critical to the organization of worker activities in insect colonies and their consequent ecological
success. The structure of this interaction network is therefore crucial to our understanding of colony organization and functioning.
In this paper, I study the properties of the interaction network in the colonies of the social wasp Ropalidia marginata. I find that the network is characterized by a uniform connectivity among individuals with increasing heterogeneity as colonies
become larger. Important network parameters are found to be correlated with colony size and I investigate how this is reflected
in the organization of work in colonies of different sizes. Finally, I test the resilience of these interaction networks by
experimental removal of individuals from the colony and discuss the structural properties of the network that are related
to resilience in a social network.
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
522.
Patrick Gautier Marco Barroca Sophie Bertrand Cyril Eraud Maria Gaillard Michael Hamman Sébastien Motreuil Gabriele Sorci Bruno Faivre 《Behavioral ecology and sociobiology》2008,62(7):1159-1166
Several environmental factors have been shown to shape the pattern of investment of carotenoids into the expression of sexual
signals. Surprisingly, the impact of the social environment has been neglected. If a carotenoid-based sexual trait is used
by females to choose a mate or by males to assess the quality of potential competitors for mates, males, in the presence of
females, should upregulate expression of the trait. We tested this hypothesis in male zebra finches that were housed either
with females or in a male-only social environment. Additionally, to investigate whether the social modulation of the expression
of a sexual trait depends on the physiological need of carotenoids, we challenged half of the males with Escherichia coli lipopolysaccharide (LPS). We found that the social environment modulated the expression of bill color, with males kept in
the presence of females harboring a redder bill at the end of the 3 weeks that the experiment lasted. Males injected with
LPS showed duller bill color regardless of the presence of females, and social interactions with females result in upregulated
bill color similarly for phosphate-buffered saline (PBS) and LPS males. Thus, social environment and immune activation had
an additive effect on the expression of bill color. The effect of social environment on plasma carotenoids was less clear.
Indeed, a first replicate of the entire experiment showed that both immune challenge and social context affected bill color,
with a negative effect of immune challenge and a positive effect of the presence of females on circulating carotenoids. However,
a second replicate of the experiment showed only a negative effect of the immune challenge. These results, therefore, suggest
that the social environment can affect the expression of carotenoid-based sexual traits under both benign and carotenoid-demanding
conditions. Whatever the signaling function of bill color (female mate choice or male–male competition for mates), the observed
flexibility may be adaptive because the expression of the signal can be modulated depending on the expected rewards or costs
associated with the presence or absence of females. Nevertheless, the mechanisms underlying such an effect are still unknown. 相似文献
523.
Yutaka Saito Anthony R. Chittenden Kotaro Mori Katsura Ito Atsushi Yamauchi 《Behavioral ecology and sociobiology》2008,63(1):33-42
The number of nests containing egg masses a female makes over her lifetime and the pattern of scattering nests vary among
species in a genus of nest-weaving spider mites (Stigmaeopsis). We hypothesized that the scattered nests of small nest builders have a previously overlooked indirect effect in that the
void nests created after predation take on a new role as hindering devices that effectively decrease predator searching efficiency.
First, we demonstrated that the experimental design used in this study is a good reflection of the nest distribution pattern
of Stigmaeopsis takahashii (an intermediate-sized nest builder) in the field. Using this species as a model, we tested how different nest-scattering
patterns affect the predator to examine how scattering may indirectly provide an anti-predation strategy by increasing a predators
searching time. Next, we observed how artificially arranged void nests disturb predatory behavior in both starved and fully
fed predator females and showed that void nests have a strong hindering effect on predators. Thus, we concluded that the nesting
behavior of this mite species not only has anti-predator effects but must also have a stabilizing effect on predator–prey
interaction systems at the population level. 相似文献
524.
Large males dominate: ecology,social organization,and mating system of wild cavies,the ancestors of the guinea pig 总被引:1,自引:0,他引:1
Matthias Asher Tanja Lippmann Jörg T. Epplen Cornelia Kraus Fritz Trillmich Norbert Sachser 《Behavioral ecology and sociobiology》2008,62(9):1509-1521
Ecological factors differently affect male and female animals and thereby importantly influence their life history and reproductive
strategies. Caviomorph rodents are found in a wide range of habitats in South America and different social and mating systems
have evolved in closely related species. This permits to study the impact of ecological factors on social evolution. In this
study, we investigated the social organization and the mating system of the wild cavy (Cavia aperea), the ancestor of the domestic guinea pig, in its natural habitat in Uruguay. Based on our laboratory investigations, we
expected a polygynous system with large males controlling access to females. Results from radiotelemetry and direct observations
showed that females occupied small stable home ranges which were largely overlapped by that of one large male, resulting in
a social organization of small harems. In some cases, small satellite males were associated with harems and intermediate-sized
roaming males were occasionally observed on the study site. However, microsatellite analyses revealed that offspring were
exclusively sired by large males of the same or neighboring harems, with a moderate degree of multiple paternity (13–27%).
Thus, the mating system of C. aperea can be described as polygynous and contrasts with the promiscuous organization described for other species of cavies (Cavia magna, Galea musteloides and Microcavia australis) living under different ecological conditions. Our findings stress the strong impact of environmental factors on social evolution
in Caviomorphs as resource distribution determines female space use and, thereby, the ability of males to monopolize females.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
525.
Colony nutritional status modulates worker responses to foraging recruitment pheromone in the bumblebee Bombus terrestris 总被引:2,自引:1,他引:1
Mathieu Molet Lars Chittka Ralph J. Stelzer Sebastian Streit Nigel E. Raine 《Behavioral ecology and sociobiology》2008,62(12):1919-1926
Foraging activity in social insects should be regulated by colony nutritional status and food availability, such that both
the emission of, and response to, recruitment signals depend on current conditions. Using fully automatic radio-frequency
identification (RFID) technology to follow the foraging activity of tagged bumblebees (Bombus terrestris) during 16,000 foraging bouts, we tested whether the cue provided by stored food (the number of full honeypots) could modulate
the response of workers to the recruitment pheromone signal. Artificial foraging pheromones were applied to colonies with
varied levels of food reserves. The response to recruitment pheromones was stronger in colonies with low food, resulting in
more workers becoming active and more foraging bouts being performed. In addition to previous reports showing that in colonies
with low food successful foragers perform more excited runs during which they release recruitment pheromone and inactive workers
are more prone to leave the nest following nectar influx, our results indicate that evolution has shaped a third pathway that
modulates bumblebee foraging activity, thus preventing needless energy expenditure and exposure to risk when food stores are
already high. This new feedback loop is intriguing since it involves context-dependent response to a signal. It highlights
the integration of information from both forager-released pheromones (signal) and nutritional status (cue) that occurs within
individual workers before making the decision to start foraging. Our results support the emerging view that responses to pheromones
may be less hardwired than commonly acknowledged.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
526.
China’s government is now promoting the Nomad Sedentarization Project (NSP) in large areas of grassland as a solution for ecological restoration and poverty alleviation. To examine the effects of this policy, we conducted in-depth interviews at two of the project’s sites and examined the social and ecological systems at village, county, and catchment scales in Jinghe County of Xinjiang. We found that (1) the NSP in one village greatly improved the household standard of living and changed their resource utilization modes; (2) the success in this village can be attributed to resources imported from the social and ecological systems at larger scales, and could not be repeated in a second nearby village with different constraints; and (3) the NSP is poorly adapted to local ecosystem characteristics, and may therefore have negative impacts at larger scales. To avoid these problems, holistic assessments are necessary to judge the NSP’s impacts on social and ecological systems at multiple scales, and the program must be implemented cautiously to account for the potential risks in ecologically vulnerable areas. 相似文献
527.
The climate change countermovement and its program of climate change denial have been well documented and studied. However, individual rationales for rejecting climate science remain under-studied. Twitter data related to Hurricane Sandy in 2012 are used to understand why individuals reject the orthodox climate consensus, using a summative content analysis of climate change denial discourses. Three major discourses are discovered: rejecting climate science because climate science is a conspiracy favoring growth of government; opposing renewable energy and energy taxation; and expressing fear of governmental abuse of power. Importantly, each discourse expressed certainty that climate science itself was a wholesale fraud; the denial discourses themselves focused far more on climate politics than on science. 相似文献
528.
Hong Wang 《中国人口.资源与环境(英文版)》2016,14(2):96-104
Corporate Environmental Responsibility (CER) is the subsystem of Corporate Social Responsibility (CSR), which continues to increase prominence in the global economy. Nowadays, CER becomes more important in corporate sustainable development. Based on Carroll’s pyramid mode of CSR, this article explores the systematic feature of CER. From a systematic perspective, it sorts out its elements, structure, function, and principles of CER. And the four levels of economic, legal, ethical, and charitable structure are emphasized. With these considerations interpreted into practice, success will be achieved in potential cost savings, technological innovation, increased public acceptance, and better relations with governments. 相似文献
529.
Climate change effects are expected to be more severe for some segments of society than others. In Mexico, climate variability associated with climate change has important socio-economic and environmental impacts. From the central mountainous region of eastern Veracruz, Mexico, we analyzed data of total annual precipitation and mean annual temperature from 26 meteorological stations (1922–2008) and from General Circulation Models. We developed climate change scenarios based on the observed trends with projections to 2025, 2050, 2075, and 2100, finding considerable local climate changes with reductions in precipitation of over 700 mm and increases in temperature of ~9°C for the year 2100. Deforested areas located at windward were considered more vulnerable, representing potential risk for natural environments, local communities, and the main crops cultivated (sugarcane, coffee, and corn). Socio-economic vulnerability is exacerbated in areas where temperature increases and precipitation decreases.
Electronic supplementary material
The online version of this article (doi:10.1007/s13280-015-0690-4) contains supplementary material, which is available to authorized users. 相似文献530.