Nest-building by crested tit Parus cristatus males: an analysis of costs and benefits

In a population of crested tits in Belgium, one out of three breeding males participated in nest-building. Since variation in the amount of nest-building among 11 building males was low, analysis of male nest-building allowed a logistic regression design. The probability of building increased with male condition and for late nests. The effect of male condition decreased with date, and date was the only factor predicting nest-building for repeat broods. The effect of male condition on nest-building suggests that building entails important costs for males. Based on correlative data, we argue that building by males shortens the interval between the start of nest-building and the onset of egg-laying by about 5 days. Since clutch size, incubation and nestling time did not differ between early and late broods, male nest-building apparently affects fledging date. Since early fledgers (early dispersers) are more likely to settle in future winter flocks, building behaviour by crested tit males should be favoured by natural selection. So far, male nest-building in hole-breeding birds might have been overlooked due to the widespread use of artificial nest-boxes in behavioural studies.     

The effects of job demands and control on employee attendance and satisfaction

We examined the impact of stressful job demands on employee attitudes and attendance. Using Karasek's (1979) theory of job decision latitude as the conceptual foundation, we hypothesized that mental and physical work demands would interact with employee beliefs of personal control. Survey data from 90 male manufacturing employees regarding their control beliefs were combined with objective job analysis data concerning mental and physical demands and one year's worth of archival data regarding unexcused absences, sick days, and days tardy. There were significant interactions between control and objective psychological demands that indicated that these demands were associated with higher levels of tardiness and sick days only under conditions of low perceived control. In contrast, subjective workload ratings showed no relationship with tardiness and sick days, but, in interaction with control, predicted work satisfaction and voluntary absence. We discussed these results in terms of a stress process that affects health-related attendance independent of employee attitudes.     

Review of present European environmental policies and legislation involving cultural heritage

Cultural heritage is being addressed by a number of charters and conventions and it is clear that its consideration within decision-making processes is progressively becoming a real challenge, both for developers and public authorities. Against this background, this paper reviews the environmental assessment framework developed by the European Community, as this should increasingly influence decision making about cultural heritage in an urban setting. The legislative framework for access to environmental information is also reviewed because of its relevance to the decision-making process.The Directives on Environmental Impact Assessment and Strategic Environmental Assessment both require a consideration of cultural heritage in decision making. This requirement can go some way to addressing the paradox in the European Community's position whereby the community wishes to conserve and enhance its own cultural identity whilst, at the same time, cultural heritage is usually defined at a local level. The present paper suggests that, given their flexibility, the two European Community directives on environmental assessment constitute a promising opportunity to address this seeming paradox, but that there is a significant gap between legal obligations and the methodological tools to meet them.     

New birds on the block: new neighbors increase defensive costs for territorial male willow ptarmigan

Previous researchers have hypothesized that site-faithful animals may benefit from the presence of familiar neighbors. This study compares the relative costs of territorial defense against new and former neighbors by male willow ptarmigan (Lagopus lagopus). Territorial defense against new neighbors appeared to require a greater expenditure of both time and effort than did defense against former neighbors. Territorial males that had several new neighbors spent a higher proportion of time fighting than did males with fewer new neighbors, and males with both new and former neighbors spent a greater amount of time fighting with their new neighbors, on average, than with their former neighbors. In addition, fights with new neighbors occurred relatively more frequently and were longer than fights with former neighbors. Finally, fights involving new neighbors tended to escalate to higher levels than fights between former neighbors. Reduced defensive costs for site-faithful, territorial males may provide one explanation for the tendency of males to be more site-faithful than females in many species.     

Small queens in the ant Ectatomma tuberculatum: a new case of social parasitism

Social parasites exploit the worker force of colonies of other social insects to rear their own young. Social parasitism occurs in several Hymenoptera and is particularly common in several tribes of the ant subfamilies Myrmicinae and Formicinae. Here, we document the occurrence of miniaturized queens (microgynes) in colonies of Ectatomma tuberculatum, an ant belonging to the subfamily Ectatomminae. Behavioral observations and genetic analyses show that microgynes concentrate their reproductive efforts almost exclusively on the production of sexual offspring (microgynes and males), whereas the regular, large queens (macrogynes) produce workers in addition to sexuals. According to mitochondrial and nuclear markers, gene flow between microgynes and macrogynes is extremely limited. Whereas the co-occurrence of microgynes and macrogynes in the related species Ectatomma ruidum constitutes an intraspecific polymorphism associated with alternative dispersal tactics, microgynes found in colonies of E. tuberculatum appear to be a distinct species and to represent the first case of social parasitism in the poneromorph subfamilies of ants.