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Summary Experimental hives obtained from cordovan queens that were instrumentally inseminated with semen from one cordovan and one Italian drone were set up and allowed to swarm. Cordovan provides a resessive genetic marker system (cuticle color) so that the workers from the cordovan and Italian male lines are distinguishable. Our results show that these patrilineal worker groups segregate non-randomly during colony fission and this segregation cannot be explained by observed age structure. Evidence of innate kin recognition in bees has been previously established. We argue that kin recognition could be responsible for the observed non-random grouping of kin during swarming.  相似文献   
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The structure of dominance relationships among individuals in a population is known to influence their fitness, access to resources, risk of predation, and even energy budgets. Recent advances in global positioning system radio telemetry provide data to evaluate the influence of social relationships on population spatial structure and ranging tactics. Using current models of socio-ecology as a framework, we explore the spatial behaviors relating to the maintenance of transitive (i.e., linear) dominance hierarchies between elephant social groups despite the infrequent occurrence of contests over resources and lack of territorial behavior. Data collected from seven families of different rank demonstrate that dominant groups disproportionately use preferred habitats, limit their exposure to predation/conflict with humans by avoiding unprotected areas, and expend less energy than subordinate groups during the dry season. Hence, our data provide strong evidence of rank derived spatial partitioning in this migratory species. These behaviors, however, were not found during the wet season, indicating that spatial segregation of elephants is related to resource availability. Our results indicate the importance of protecting preexisting social mechanisms for mitigating the ecological impacts of high density in this species. This analysis provides an exemplar of how behavioral research in a socio-ecological framework can serve to identify factors salient to the persistence and management of at risk species or populations. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
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A system of ordinary differential equations is presented as being appropriate for modelling the impact of stress on the temporal behaviour of certain components within an ecosystem. The modelling problem is fist discussed in general terms and then in terms specifically relating to the impact of recreational activities (hunting, fishing, sightseeing, etc.) on a coniferous forest ecosystem.Using crude data, the model is used to simulate over a 3-year period the biomass levels of four compartments of the ecosystem (viz, timber, deer, fish and forage) in the absence of recreational activities. These results are then contrasted with simulation results obtained by introducing a “moderate” and then “high” degree of recreational activity, as well as the response of the system under moderate recreation to management strategies involving the construction of dams and the harvesting of timber.  相似文献   
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To supplement an epidemiological investigation into respiratory cancer, a synthetic fabric called tak was used to study the deposition of atmospheric metal pollution within the town of Armadale, central Scotland. Pollution maps showed high concentrations of several metals in areas close to the town's steel foundry and in a second area in the north of the town. Through further statistical analyses, those metals were identified which had probably been emitted by the foundry, and temporal variations in metal deposition patterns were examined. The advantages of this method of low technology sampling, which include the low cost and a high density of sampling sites, are described.  相似文献   
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Summary We used intensive livetrapping to examine natal dispersal and philopatry in prairie voles (Microtus ochrogaster). The majority of male (70.0%) and female prairie voles (75.1 %) remained at the natal nest until death. Those males and females that did disperse left home at about the same age (45–55 days) and moved similar distances (28–33 m). Dispersal was more common (1) from small natal groups than from large natal groups, (2) following disappearance of parents, (3) during the breeding period than during the nonbreeding period, and (4) at low population densities than at high densities. Dispersal was not associated with level of competition for mates within natal groups, and dispersers did not differ from nondispersers in body weight. Our data do not support competition for mates or resources as important factors influencing natal dispersal in prairie voles. The absence of sex differences in dispersal tendency or distance, and our fording that more than half of dispersers had become reproductive before leaving the natal nest, lead us to suggest that inbreeding avoidance is not a primary function of dispersal in this species. Dispersal was, however, more common when potential mates within the natal group were relatives than when they were nonrelatives. Although not tested here, if family members avoid mating with one another through patterns of mate choice, then some animals may leave home in search of mates. The precise benefits associated with philopatry in prairie voles remain to be identified. Correspondence to: B. McGuire at her present address  相似文献   
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Winnie JA  Cross P  Getz W 《Ecology》2008,89(5):1457-1468
Top-down effects of predators on prey behavior and population dynamics have been extensively studied. However, some populations of very large herbivores appear to be regulated primarily from the bottom up. Given the importance of food resources to these large herbivores, it is reasonable to expect that forage heterogeneity (variation in quality and quantity) affects individual and group behaviors as well as distribution on the landscape. Forage heterogeneity is often strongly driven by underlying soils, so substrate characteristics may indirectly drive herbivore behavior and distribution. Forage heterogeneity may further interact with predation risk to influence prey behavior and distribution. Here we examine differences in spatial distribution, home range size, and grouping behaviors of African buffalo as they relate to geologic substrate (granite and basalt) and variation in food quality and quantity. In this study, we use satellite imagery, forage quantity data, and three years of radio-tracking data to assess how forage quality, quantity, and heterogeneity affect the distribution and individual and herd behavior of African buffalo. We found that buffalo in an overall poorer foraging environment keyed-in on exceptionally high-quality areas, whereas those foraging in a more uniform, higher-quality area used areas of below-average quality. Buffalo foraging in the poorer-quality environment had smaller home range sizes, were in smaller groups, and tended to be farther from water sources than those foraging in the higher-quality environment. These differences may be due to buffalo creating or maintaining nutrient hotspots (small, high-quality foraging areas) in otherwise low-quality foraging areas, and the location of these hotspots may in part be determined by patterns of predation risk.  相似文献   
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