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161.
Piyamas Nanork Siriwat Wongsiri Benjamin P. Oldroyd 《Behavioral ecology and sociobiology》2006,61(1):91-97
Honeybee (Apis) workers cannot mate, but retain functional ovaries. When colonies have lost their queen, many young workers begin to activate their ovaries and lay eggs. Some of these eggs are reared, but most are not and are presumably eaten by other workers (worker policing). Here we explore some of the factors affecting the reproductive success of queenless workers of the red dwarf honeybee Apis florea. Over a 2-year period we collected 40 wild colonies and removed their queens. Only two colonies remained at their translocated site long enough to rear males to pupation while all the others absconded. Absconding usually occurred after worker policing had ceased, as evidenced by the appearance of larvae. Dissections of workers from eight colonies showed that in A. florea, 6% of workers have activated ovaries after 4 days of queenlessness, and that 33% of workers have activated ovaries after 3 weeks. Worker-laid eggs may appear in nests within 4 days and larvae soon after, but this is highly variable. As with Apis mellifera, we found evidence of unequal reproductive success among queenless workers of A. florea. In the two colonies that reared males to pupation and which we studied with microsatellites, some subfamilies had much higher proportions of workers with activated ovaries than others. The significance of absconding and internest reproductive parasitism to the alternative reproductive strategies of queenless A. florea workers is discussed. 相似文献
162.
Sean A. Rands Richard A. Pettifor J. Marcus Rowcliffe Guy Cowlishaw 《Behavioral ecology and sociobiology》2006,60(4):572-581
In socially foraging animals, it is widely acknowledged that the position of an individual within the dominance hierarchy of the group has a large effect upon its foraging behaviour and energetic intake, where the intake of subordinates can be reduced through socially mediated interference. In this paper, we explore the effects of interference upon group dynamics and individual behaviour, using a spatially explicit individual-based model. Each individual follows a simple behavioural rule based upon its energetic reserves and the actions of its neighbours (where the rule is derived from game theory models). We show that dominant individuals should have larger energetic reserves than their subordinates, and the size of this difference increases when either food is scarce, the intensity of interference suffered by the subordinates increases, or the distance over which dominant individuals affect subordinates increases. Unlike previous models, the results presented in this paper about differences in reserves are not based upon prior assumptions of the effects of social hierarchy and energetic reserves upon predation risk, and emerge through nothing more than a reduction in energetic intake by the subordinates when dominants are present. Furthermore, we show that increasing interference intensity, food availability or the distance over which dominants have an effect also causes the difference in movement between ranks to increase (where subordinates move more than dominants), and the distance over which dominants have an effect changes the size of the groups that the different ranks are found in. These results are discussed in relation to previous studies of intra- and interspecific dominance hierarchies. 相似文献
163.
Central-place foraging theory has been unable to explain the load selection behavior of leaf-cutting ants (Atta spp., Attini: Formicidae). We suggest that this is due to incomplete consideration of the sequence of behaviors involved in resource acquisition by these ants. Unlike most central-place foragers, leaf-cutting ants do not return to their nests with food. Instead, the leaf fragments they gather must be processed within the nest to convert them to substrate for fungal gardens. We have shown previously that leaf fragment size affects the rate of distribution and processing of leaf tissue inside laboratory nests of Atta colombica. Including these tasks in the calculation of foraging rate may help explain load selection and other features of central-place foraging by Atta colonies. Here we develop a mathematical model of the complete sequence of external and internal tasks that lead to addition of substrate to fungal gardens. Using realistic parameter values, the leaf fragment sizes predicted to maximize a colony's rate of foraging in this broad sense correspond well with the mean fragment sizes actually collected by Atta colonies in the field. The optimal fragment size for global performance in the model is below the size that would maximize the delivery rate by above-ground foragers. The globally optimal size also fails to maximize the rate of either fragment distribution or fragment processing within the nest. Our results show how maximum collective performance of an ensemble of linked tasks may require behavior that would appear suboptimal in a piecemeal analysis of tasks. 相似文献
164.
Control of reproduction in social insect colonies: individual and collective relatedness preferences in the paper wasp, Polistes annularis 总被引:1,自引:0,他引:1
David C. Queller J. M. Peters Carlos R. Solís Joan E. Strassmann 《Behavioral ecology and sociobiology》1997,40(1):3-16
Social insect colonies often have one or a few queens. How these queens maintain their reproductive monopoly, when other
colony members could gain by sharing in the reproduction, is not generally known. DNA microsatellite genotyping is used to
determine reproductive interests of various classes of colony members in the paper wasp, Polistes annularis. The relatedness estimates show that the best outcome for most individuals is to be the reproductive egg-layer. For workers,
this depends on the sex of offspring: they should prefer to lay their own male eggs, but are indifferent if the queen lays
the female eggs. The next-best choice is usually to support the current queen. As a rule, subordinates and workers should
prefer the current queen to reproduce over other candidates (though subordinates have no strong preference for the queen over
other subordinates, and workers may prefer other workers as a source of male eggs). This result supports the theory that reproductive
monopoly stems from the collective preferences of non-reproductives, who suppress each other in favor of the queen. However,
we reject the general hypothesis of collective worker control in this species because its predictions about who should succeed
after the death of the present queen are not upheld. The first successor is a subordinate foundress even though workers should
generally prefer a worker successor. If all foundresses have died, an older worker succeeds as queen, in spite of a collective
worker preference for a young worker. The results support the previous suggestion that age serves as a conventional cue serving
to reduce conflict over queen succession.
Received: 3 May 1996 / Accepted after revision: 22 September 1996 相似文献
165.
Robert E. Page Jr. Gene E. Robinson M. Kim Fondrk Medhat E. Nasr 《Behavioral ecology and sociobiology》1995,36(6):387-396
There have been numerous reports of genetic influences on division of labor in honey bee colonies, but the effects of worker genotypic diversity on colony behavior are unclear. We analyzed the effects of worker genotypic diversity on the phenotypes of honey bee colonies during a critical phase of colony development, the nest initiation phase. Five groups of colonies were studied (n = 5–11 per group); four groups had relatively low genotypic diversity compared to the fifth group. Colonies were derived from queens that were instrumentally inseminated with the semen of four different drones according to one of the following mating schemes: group A, 4 A-source drones; group B, 4 B-source drones; group C, 4 C-source drones; group D, 4 D-source drones; and group E, 1 drone of each of the A-D drone sources. There were significant differences between colonies in groups A-D for 8 out of 19 colony traits. Because the queens in all of these colonies were super sisters, the observed differences between groups were primarily a consequence of differences in worker genotypes. There were very few differences (2 out of 19 traits) between colonies with high worker genotypic diversity (group E) and those with low diversity (groups A-D combined). This is because colonies with greater diversity tended to have phenotypes that were average relative to colonies with low genotypic diversity. We hypothesize that the averaging effect of genotypic variability on colony phenotypes may have selective advantages, making colonies less likely to fail because of inappropriate colony responses to changing environmental conditions. 相似文献
166.
There is a genetic component to plasticity in age polyethism in honey bee colonies, such that workers of some genotypes become precocious foragers more readily than do workers of other genotypes, in colonies lacking older bees. Using colonies composed of workers from two identifiable genotype groups, we determined that intracolony differences in the likelihood of becoming a precocious forager are a consequence of differences in rates of behavioral development that are also evident under conditions leading to normal development. An alternative hypothesis, that differences in the likelihood of becoming a precocious forager are due to differences in general sensitivity to altered colony conditions, was not supported. In three out of three trials, workers from the genotype group that was more likely to exhibit precocious foraging in single cohort colonies also foraged at relatively younger ages in colonies in which workers exhibited normal behavioral development. In contrast, in three out of three trials, workers from the genotype group that was more likely to exhibit precocious foraging in single-cohort colonies did not show disproportionately more overaged nursing in colonies in which workers exhibited delayed development. These results indicate that genotypic differences in plasticity in age-related division of labor are based on genotypic differences in rates of behavioral development. 相似文献
167.
本文着重论述了完善的社会信用体系对于规范市场经济秩序,促进我国经济的持续、稳定、健康发展有着十分重要的意义。为此,档案行政管理部门应该主动找准自己的位置,履行自己的职责,并有所作为。从而充分发挥档案行政管理部门的自身优势,倾力打造跨行业、跨部门的信用档案信息平台。使全社会形成一种有序的竞争环境。 相似文献
168.
169.
170.
Jianguo Sun Yangjin Kim Christopher J. Schmitt 《Environmental and Ecological Statistics》2003,10(4):419-428
The National Contaminant Biomonitoring Program (NCBP) was initiated in 1967 as a component of the National Pesticide Monitoring program. It consists of periodic collection of freshwater fish and other samples and the analysis of the concentrations of persistent environmental contaminants in these samples. For the analysis, the common approach has been to apply the mixed two-way ANOVA model to combined data. A main disadvantage of this method is that it cannot give a detailed temporal trend of the concentrations since the data are grouped. In this paper, we present an alternative approach that performs a longitudinal analysis of the information using random effects models. In the new approach, no grouping is needed and the data are treated as samples from continuous stochastic processes, which seems more appropriate than ANOVA for the problem. 相似文献