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1.
Jürgen Gadau Pia J. Gertsch Jürgen Heinze Pekka Pamilo Bert Hölldobler 《Behavioral ecology and sociobiology》1998,44(1):23-33
Multilocus DNA fingerprinting and microsatellite analysis were used to determine the number of queens and their mating frequencies
in colonies of the carpenter ant, Camponotus ligniperdus (Hymenoptera: Formicidae). Only 1 of 61 analyzed queens was found to be double-mated and the population-wide effective mating
frequency was therefore 1.02. In the studied population, 8 of 21 mature field colonies (38%) contained worker, male, or virgin
queen genotypes which were not compatible with presumed monogyny and therefore suggested oligogyny, i.e., the cooccurrence
of several mutually intolerant queens within one colony. Estimated queen numbers in oligogynous colonies ranged between two
and five. According to the results of the genetic analysis, most of the queens coexisting in oligogynous colonies were not
closely related. Pleometrosis is very rare and queenless colonies adopt mated queens both in the laboratory and field. Therefore,
the most plausible explanation for the origin of oligogynous colonies in C. ligniperdus is the adoption of unrelated queens by orphaned mature colonies. The coexistence of unrelated, but mutually intolerant queens
in C. ligniperdus colonies demonstrates that oligogyny should be considered as a phenomenon distinct from polygyny.
Received: 18 December 1997 / Accepted after revision: 20 June 1998 相似文献
2.
Summary. Workers of the amblyoponine species Mystrium rogeri employ trail communication during recruitment to food sources and new nest sites. The trail pheromone originates from a hitherto
unknown sternal gland located in the 7th abdominal sternite. The recruiting ant deposits the gland secretions by a special
gaster-dragging behavior. The recruitment behavior can be complemented by a rapid vertical body shaking performed by some
recruiting ants inside the nest. M. rogeri workers possess a large pygidial gland, the secretion of which elicits a repellent response in other ant species.
Received 25 May 1998; accepted 15 June 1998. 相似文献
3.
Molecular genetic variation in tarpon (<Emphasis Type="Italic">Megalops atlanticus</Emphasis> Valenciennes) in the northern Atlantic Ocean 总被引:2,自引:0,他引:2
A.?L.?McMillen-JacksonEmail author T.?M.?Bert H.?Cruz-Lopez S.?Seyoum T.?Orsoy R.?E.?Crabtree 《Marine Biology》2005,146(2):253-261
The tarpon (Megalops atlanticus) is a highly valued game fish and occasional food fish in the eastern and western Atlantic Ocean. Tarpon have a high capacity for dispersal, but some regional biological differences have been reported. In this study we used two molecular genetic techniques—protein electrophoresis of nuclear DNA loci, and restriction fragment length polymorphism analysis of the mitochondrial DNA (mtDNA)—to assess this species population genetic structure in the eastern (coastal waters off Gabon and Sierra Leone, Africa) and western (coastal waters off Florida, Caribbean Sea) Atlantic Ocean north of the equator. Genetic differentiation was observed between tarpon from Africa and tarpon from the western Atlantic Ocean. A unique allele and haplotype, significant differences in allozyme allele and mtDNA haplotype frequencies between the African and western Atlantic samples, and significant FST analyses suggest that levels of gene flow between tarpon from these two regions is low. Among the western Atlantic Ocean collections, genetic diversity values and allele and haplotype frequencies were similar. AMOVA analyses also showed a degree of genetic relatedness among most of the western Atlantic Ocean collections: however, some significant population structuring was detected in the allozyme data. A regional jackknifed FST analysis indicated the distinction of the Costa Rica population from the other western Atlantic populations and, in pairwise analyses, FST values tended to be higher (i.e., genetic relatedness was lower) when the Costa Rican sample was paired with any of the other western Atlantic samples. These data suggest that Costa Rican tarpon could be partially isolated from other western Atlantic tarpon populations. Ultimately, international cooperation will be essential in the management of this species in both the eastern and western Atlantic Ocean.Communicated by P.W. Sammarco, Chauvin 相似文献
4.
Developing Effective Decision Support for the Application of “Gentle” Remediation Options: The GREENLAND Project 下载免费PDF全文
Andy Cundy Paul Bardos Markus Puschenreiter Nele Witters Michel Mench Valerie Bert Wolfgang Friesl‐Hanl Ingo Müller Nele Weyens Jaco Vangronsveld 《补救:环境净化治理成本、技术与工艺杂志》2015,25(3):101-114
Gentle remediation options (GRO) are risk management strategies/technologies that result in a net gain (or at least no gross reduction) in soil function as well as risk management. They encompass a number of technologies, including the use of plant (phyto‐), fungi (myco‐), and/or bacteria‐based methods, with or without chemical soil additives or amendments, for reducing contaminant transfer to local receptors by in situ stabilization, or extraction, transformation, or degradation of contaminants. Despite offering strong benefits in terms of risk management, deployment costs, and sustainability for a range of site problems, the application of GRO as practical on‐site remedial solutions is still in its relative infancy, particularly for metal(loid)‐contaminated sites. A key barrier to wider adoption of GRO relates to general uncertainties and lack of stakeholder confidence in (and indeed knowledge of) the feasibility or reliability of GRO as practical risk management solutions. The GREENLAND project has therefore developed a simple and transparent decision support framework for promoting the appropriate use of gentle remediation options and encouraging participation of stakeholders, supplemented by a set of specific design aids for use when GRO appear to be a viable option. The framework is presented as a three phased model or Decision Support Tool (DST), in the form of a Microsoft Excel‐based workbook, designed to inform decision‐making and options appraisal during the selection of remedial approaches for contaminated sites. The DST acts as a simple decision support and stakeholder engagement tool for the application of GRO, providing a context for GRO application (particularly where soft end‐use of remediated land is envisaged), quick reference tables (including an economic cost calculator), and supporting information and technical guidance drawing on practical examples of effective GRO application at trace metal(loid) contaminated sites across Europe. This article introduces the decision support framework. ©2015 Wiley Periodicals, Inc. 相似文献
5.
Population structure of the Spanish sardine Sardinella aurita: natural morphological variation in a genetically homogeneous population 总被引:1,自引:0,他引:1
The importance of larval dispersal in determining the distribution and abundance of benthic marine organisms is well recognized; however, the contribution of post-larval dispersal has not been measured. I compared the dispersal of swimming larvae with that of rafting colonies in a population of compound ascidians, Botrylloides sp., living attached to leaves of the eelgrass Zostera marina in Tomales Bay, California, USA in 1990–1992. Colonies rafting on broken eelgrass traveled over 200 times farther and had comparable recruitment success relative to swimming larvae. The recruitment of rafting colonies into new habitats was facilitated by the ability of thesecolonial animals to grow asexually onto surrounding substrata. Rafting colonies brooded larvae that were subsequently relased after the colony settled into a new habitat. These results suggest that colonization of new habitats can occur by post-larvae as well as larvae, and that long-range dispersal by species with short-lived larvae may occur by post-larval rafting. 相似文献
6.
This paper describes how energy policy can be evaluated in practice. The goal is to make policy makers aware of how an evaluation can be based on scientific principles and to help economists appreciate how an evaluation can be performed if strong empirical evidence is lacking. We have built a basic evaluation framework and have applied this to a selection of Dutch energy policy instruments, namely production subsidies and their complementary non-financial instrument, DEN-B. Our evaluation criterion was effectiveness, defined as the extent to which policy instruments contribute to achieving policy goals. The evaluation was based on existing ex post evaluations complemented by interviews and other available data. We conclude that production subsidies and DEN-B were (partly) effective. Furthermore, the Dutch government increased effectiveness by reconsidering the design of production subsidies. We also formulate lessons for future policy evaluations and energy markets policies. 相似文献
7.
Bert Brunekreef Danny Houthuijs Lyanne Dijkstra Jan S.M. Boleij 《Journal of the Air & Waste Management Association (1995)》2013,63(9):1252-1256
Elevated concentrations of nitrogen dioxide (NO2) are produced in the home by the use of unvented gas appliances. In studies on potential health effects of Indoor exposure to NO2, exposure has mostly been estimated from the presence or absence of sources like gas cookers in the home. This leads to misclassification of exposure, as NO2 concentrations in the home depend also on source use, ventilation habits, time budgets, etc. The availability of cheap, passive monitoring devices has made it possible to measure Indoor concentrations of NO2 directly in health effects studies, albeit with averaging times of one to several days. So far, it has not been evaluated whether this increases the sensitivity of a study to detect health effects of NO2. In this paper, a comparison is made between NO2 sources and weekly average indoor NO2 measurements, as predictors of pulmonary function in a study among children aged 6–12 years. The relationship between exposure and lung functions was found to be generally non-significant in this study. The results further suggested that in this study, measuring Indoor NO2 concentrations with passive monitors offered no advantage over the simple use of source presence as exposure variable. 相似文献
8.
Discrimination of different social companions in spectacled parrotlets (Forpus conspicillatus): evidence for individual vocal recognition 总被引:1,自引:0,他引:1
Ralf Wanker Jasmin Apcin Bert Jennerjahn Birte Waibel 《Behavioral ecology and sociobiology》1998,43(3):197-202
Individual recognition is generally assumed to be a prerequisite for establishing and maintaining a complex social system.
Indeed, there is good evidence that highly social species have complex systems of vocal communication with individual recognition
by acoustic cues. In this study, we provide experimental evidence that vocal class and individual recognition is present in
a non-passerine bird, the spectacled parrotlet (Forpus conspicillatus). Spectacled parrotlets live in a complex system of social relationships. Soon after fledging, the young establish close
sibling relationships which are important for successful socialization, pairing and reproduction. In a series of playback
experiments we tested if spectacled parrotlets use contact calls for vocal recognition. The results showed that spectacled
parrotlets discriminate between the contact calls of different social categories. Adult birds preferred to respond to the
contact calls of their mates. Subadult individuals recognized the contact calls of their siblings. During the period of pair
bond formation, the affiliative contacts to the siblings decrease, but the parrotlets continue to respond to the calls of
their siblings. This is the first evidence that vocal sibling recognition might outlast the period of strong sibling interaction
and extends into the period of pair bond formation. In cases of mate loss or divorce, the acoustic contact to their siblings
might facilitate the re-establishment of close sibling relationships.
Received: 29 October 1997 / Accepted after revision: 5 April 1998 相似文献
9.
In ant societies, workers do not usually reproduce but gain indirect fitness benefits from raising related offspring produced
by the queen. One of the preconditions of this worker self-restraint is sufficient fertility of the queen. The queen is, therefore,
expected to signal her fertility. In Camponotus floridanus, workers can recognize the presence of a highly fertile queen via her eggs, which are marked with the queen's specific hydrocarbon
profile. If information on fertility is encoded in the hydrocarbon profile of eggs, we expect workers to be able to differentiate
between eggs from highly and weakly fertile queens. We found that workers discriminate between these eggs solely on the basis
of their hydrocarbon profiles which differ both qualitatively and quantitatively. This pattern is further supported by the
similarity of the egg profiles of workers and weakly fertile queens and the similar treatment of both kinds of eggs. Profiles
of queen eggs correspond to the cuticular hydrocarbon profiles of the respective queens. Changes in the cuticular profiles
are associated with the size of the colony the queen originates from and her current egg-laying rate. However, partial correlation
analysis indicates that only colony size predicts the cuticular profile. Colony size is a buffered indicator of queen fertility
as it is a consequence of queen productivity within a certain period of time, whereas daily egg-laying rate varies due to
cyclical oviposition. We conclude that surface hydrocarbons of eggs and the cuticular profiles of queens both signal queen
fertility, suggesting a major role of fertility signals in the regulation of reproduction in social insects. 相似文献
10.
Behavioral Ecology and Sociobiology - Predation risk is vital in determining habitat quality. But landscapes of fear are complex and dynamic, such as temperate deciduous forests characterized by... 相似文献