Kin discrimination in the spotted hyena (<Emphasis Type="Italic">Crocuta crocuta</Emphasis>): nepotism among siblings

We examined patterns of affiliation, association, and aggression to inquire whether spotted hyenas (Crocuta crocuta) can distinguish among various groups of maternal and paternal siblings. If so, and if these animals conform to predictions of kin selection theory, then behavioral interactions among hyenas should vary with relatedness. We also considered familiarity-based recognition and phenotype matching as mechanisms hyenas might use to recognize kin. Patterns of affiliative behavior indicated that hyenas favored full-sibling littermates over half-sibling littermates or any other group of half-siblings. Rates of dyadic aggression generally did not vary with kinship. Hyenas associated more closely with half-sibling littermates than with non-littermate half-siblings, and hyenas affiliated more with maternal half-siblings than with paternal half-siblings, suggesting that familiarity-based cues might mediate discrimination among these sibling classes. In addition, operation of a phenotype-matching mechanism was suggested by the preference hyenas demonstrated during affiliative interactions for full- over half-sibling littermates, and by their lack of preference in these interactions for half-sibling littermates over non-littermate half-siblings. Phenotype matching was also suggested by our observation that paternal half-siblings cooperated more, and fought less, than did non-kin. Our data indicate that hyenas can discriminate among various types of siblings, that their social behavior conforms to predictions of kin selection theory, and that they recognize kin using mechanisms of both familiarity and phenotype matching.Communicated by S. Alberts     

A dispersal model for larvae of the deep sea red crab Geryon quinquedens based upon behavioral regulation of vertical migration in the hatching stage

Behavioral responses to gravity, hydrostatic pressure, and thermoclines are described for Stage I zoeae of the deep sea red crab Geryon quinquedens Smith. Survival and rate of development as a function of temperature is presented for all larval stages. Although temperatures between 10° and 25°C have no direct effect upon survival, development time is five times longer at 10°C than at 25°C. Stage I larvae show strong negative response to gravity. Swimming rate increases with an increase in pressure up to 20 atm above ambient at 11°C, but not at 15°C. Swimming rates at 15°C are higher than those measured at 11°C at each pressure tested. Stage I larvae readily penetrate sharp thermoclines. Potential dispersal ranges of G. quinquedens larvae in the Mid-Atlantic Bight are suggested based on larval behavior, development time, and coastal hydrography. A testable recruitment model is proposed for G. quinquedens.Contribution no. 1365 of the Center for Environmental and Estuarine Studies     

What does it mean when climate models agree? A case for assessing independence among general circulation models

Climate modelers often use agreement among multiple general circulation models (GCMs) as a source of confidence in the accuracy of model projections. However, the significance of model agreement depends on how independent the models are from one another. The climate science literature does not address this. GCMs are independent of, and interdependent on one another, in different ways and degrees. Addressing the issue of model independence is crucial in explaining why agreement between models should boost confidence that their results have basis in reality.     

Should we be “challenging” employees?: A critical review and meta‐analysis of the challenge‐hindrance model of stress

The challenge‐hindrance model of stress proposes that stressors can be divided into two distinct groups: those that challenge employees and those that hinder employees. This critical review seeks to explain the history of the model and its basic tenets, while succinctly summarizing the findings of existing studies based on the model. A thorough search of the stress literature uncovered 32 studies that specifically examined the relationship between challenge and hindrance stressors and important personal/organizational variables. Results were reviewed and analyzed, specifically by describing past meta‐analyses on the model, looking at the overall pattern of results from primary studies, and meta‐analyzing the relationships presented in those papers. This synthesis suggests that although there are some differential relationships of challenge and hindrance stressors with organizational variables (e.g., performance and engagement), the relationships to other key variables, such as counterproductive work behaviors, psychological strains, and physical health, are consistently negative for both challenge and hindrance stressors. Thus, we propose that stress research move away from the current challenge‐hindrance model in favor of other established models and/or a more appraisal‐based approach.     

Farmers' Motivations for Adopting Conservation Practices along Riparian Zones in a Mid-western Agricultural Watershed

In the agricultural Mid-west, riparian corridors are vital for protecting biodiversity and water quality. The cumulative management decisions of hundreds of private landowners have a tremendous impact on this riparian zone. This study of 268 farmers in a typical Mid-western watershed in Michigan looked at farmer's motivations for adopting conservation practices, their current management practices along their rivers and drains as well as their future management plans. The results of the study showed that farmers are intrinsically motivated to practise conservation by such factors as their attachment to their land, rather than by motivations such as receiving economic compensation. Farmers are also likely to engage in conservation practices that make their farm appear well-managed. Furthermore, those farmers with strong intrinsic motivations were likely to adopt conservation practices that protect streams, such as maintaining a woody vegetative buffer or practicing no-till farming. This study shows that protecting riparian resources in agricultural watersheds requires strategies for conservation that respect farmers' attachment to their land and their desire to practise good stewardship.     

The Wreck of Amtrak's Sunset Limited: News Coverage of a Mass Transport Disaster

Using the 1993 crash of Amtrak's Sunset Limited in Mobile, Alabama, this study examines the safety education provided by seven newspapers. A total of 117 news stories were analysed for five primary themes: overall story category, passenger safety theme, train personnel safety theme, train safety theme and rescue safety. Sixty-three per cent were found to contain at least one safety theme paragraph within the larger story. A total of 631 paragraphs were identified as safety theme paragraphs, 32 per cent of which were passenger safety themes, 8 per cent were train personnel safety, 31 per cent were train safety and 29 per cent were rescue safety themes. As in previous research, safety themes rarely appeared alone; more often than not, a story contained a mixture of all themes. Some safety themes appeared more frequently than others, but overall, the safety themes present a complete view of the safety issues surrounding the crash.
Safety themes are embedded within a story framework which reflects the three stages of disaster news work. Images of normalcy tragically disrupted by the crash abound as do images of passengers escaping and aiding others. Disaster relief personnel and aviation officials are shown working to restore order and solve the mystery of the crash. Within this framework we can learn what to expect when a train crashes and what we might have to do in a similar situation.