Fecal glucocorticoids reflect socio-ecological and anthropogenic stressors in the lives of wild spotted hyenas

Our aim was to identify natural and anthropogenic influences on the stress physiology of large African carnivores, using wild spotted hyenas (Crocuta crocuta) as model animals. With both longitudinal data from a single social group, and cross-sectional data from multiple groups, we used fecal glucocorticoids (fGC) to examine potential stressors among spotted hyenas. Longitudinal data from adult members of a group living on the edge of the Masai Mara National Reserve, Kenya, revealed that fGC concentrations were elevated during two periods of social upheaval among adults, especially among younger females; however, prey availability, rainfall, and presence of lions did not influence fGC concentrations among hyenas. Our results suggested that anthropogenic disturbance in the form of pastoralist activity, but not tourism, influenced fGC concentrations among adult male hyenas; rising concentrations of fGC among males over 12 years were significantly correlated with increasing human population density along the edge of the group\u27s home range. As hyenas from this social group were frequently exposed to anthropogenic disturbance, we compared fGC concentrations among these hyenas with those obtained concurrently from hyenas living in three other groups undisturbed by pastoralist activity. We found that fGC concentrations from the undisturbed groups were significantly lower than those in the disturbed group, and we were able to rule out tourism and ecological stressors as sources of variation in fGC among the populations. Thus it appears that both social instability and anthropogenic disturbance, but not the ecological variables examined, elevate fGC concentrations and represent stressors for wild spotted hyenas. Further work will be necessary to determine whether interpopulation variation in stress physiology predicts population decline in groups exposed to intensive anthropogenic disturbance

Do female hyaenas choose mates based on tenure?

In their investigation into whether female mate-choice drives male dispersal, Höner et al.argue that female spotted hyaenas (Crocuta crocuta) prefer mates whose tenure in the social group is less than the females’ age, to avoid paternal incest, and suggest that male dispersal reflects this preference. However, we are not persuaded that females choose mates on the basis of tenure because Höner et al. overlook the alternative hypothesis that dispersal status itself is important in female mate-choice, such that females prefer immigrants over natal males. Like mate-choice based on tenure, choice based on dispersal status reduces the risk of incest

Society, demography and genetic structure in the spotted hyena

Spotted hyenas (Crocuta crocuta) are large mammalian carnivores, but their societies, called \u27clans\u27, resemble those of such cercopithecine primates as baboons and macaques with respect to their size, hierarchical structure, and frequency of social interaction among both kin and unrelated group-mates. However, in contrast to cercopithecine primates, spotted hyenas regularly hunt antelope and compete with group-mates for access to kills, which are extremely rich food sources, but also rare and ephemeral. This unique occurrence of baboon-like sociality among top-level predators has favoured the evolution of many unusual traits in this species. We briefly review the relevant socio-ecology of spotted hyenas, document great demographic variation but little variation in social structure across the species\u27 range, and describe the long-term fitness consequences of rank-related variation in resource access among clan-mates. We then summarize patterns of genetic relatedness within and between clans, including some from a population that had recently gone through a population bottleneck, and consider the roles of sexually dimorphic dispersal and female mate choice in the generation of these patterns. Finally, we apply social network theory under varying regimes of resource availability to analyse the effects of kinship on the stability of social relationships among members of one large hyena clan in Kenya. Although social bonds among both kin and non-kin are weakest when resource competition is most intense, hyenas sustain strong social relationships with kin year-round, despite constraints imposed by resource limitation. Our analyses suggest that selection might act on both individuals and matrilineal kin groups within clans containing multiple matrilines

Ecological determinants of survival and reproduction in the spotted hyena

Large carnivores play a key role in the structuring and dynamics of many ecosystems, yet the factors influencing dynamics of carnivore populations themselves are often poorly understood. Spotted hyenas (Crocuta crocuta) are the most abundant large carnivores in many African ecosystems. We describe demographic patterns in a population of spotted hyenas observed continuously for 15.5 years, and assess the effects of per capita prey availability, interspecific competition, rainfall, anthropogenic disturbance, and disease on 2 key determinants of population dynamics: reproduction and survival. Annual reproduction, survival of juveniles (i.e., recruitment to adulthood), and mortality of adults varied among years of the study. Per capita prey availability and group size both had positive effects on reproduction, whereas interspecific competition with lions had a negative effect. Competition with lions and rainfall both had negative effects on survival of juveniles. We suggest that the negative effect of rainfall on survival may be mediated by increased rates of human-carnivore conflict during periods of heavy rain, although human population size did not influence survival or reproduction directly. Disease had no substantial effect on this hyena population, despite occurrence of at least 2 disease outbreaks among sympatric carnivores during the study. By focusing on demographic processes that determine population growth (i.e., survival and reproduction), this study highlights the importance of both top-down and bottom-up forces acting on populations of large carnivores. These findings also add to a growing literature suggesting that interspecific competition may be more important than previously recognized in the dynamics of populations of large carnivores

The evolution of photoperiodic response systems and seasonal GnRH plasticity in birds

Animals’ lives are typically subdivided into distinct stages, some of which (e.g. breeding) contribute to fitness through enhancing current reproductive success, and some of which (e.g. molting and migration in birds; hibernation in mammals) contribute to fitness through enhancing survival and, therefore, future reproductive opportunities. There is often a trade-off between these two kinds of processes, either because they are temporally incompatible with one another (e.g. migration precludes simultaneous nesting in birds) or because they are energetically incompatible with one another (e.g. successful molting appears to be incompatible with simultaneous nesting in many birds). Consequently, adaptations facilitating appropriate timing and coordination of different life-cycle stages are arguably as important to fitness as are more obvious adaptations such as feeding morphologies and predator avoidance. Mechanisms that facilitate coordination of life-cycle events with the annual cycle of changes in the environment are therefore expected to evolve in response to selection imposed by different environmental challenges. This article focuses on how mechanisms affecting the timing of, and transitions between, life-cycle stages, particularly breeding, have evolved in birds. Through comparative analyses, we show that photorefractoriness and one neuroendocrine correlate of it—plasticity of the gonadotropin releasing hormone system—have evolved in ways that facilitate different degrees of flexibility in timing of the transition from breeding to molting in different environments. We argue that the nature of the mechanistic adaptations will affect the capacity for adaptive adjustments to changing environmental conditions both in the short term (plasticity inherent in individuals) and in the long term (evolutionary responses of populations to selection)

Strategic Analysis for the Open Source Institute at Simon Fraser University

Over the last decades, Open Source Software (OSS) has become increasingly popular and moved into the mainstream software industry. Our project\u27s goal is to investigate the need for an Open Source Institute (OSI) within Simon Fraser University (SFU). We performed a literature review and interviewed IT specialists from various local companies. We identified some barriers to the adoption of OSS, including lack of working knowledge of OSS, lack of multi-tier technical support, and legal concerns. Our analysis confirmed the need for this institute to promote OSS. We recommend that the SFU-OSI should broker technical support for OSS, to increase the level of awareness by organizing events and incubator-type initiatives, to offer various levels of training, to create standards and frameworks for user-friendly and well-documented OSS, to mine the undocumented innovations embedded in mature OSS, and to work with governments to leverage OSS for the betterment of society

Creating a Flexible IT Organization

In 2004, the nearly billion dollar software company Business Objects undertook a major acquisition. Now, the business is looking to improve operations and position itself as a major player in the business intelligence market. This paper focuses on how Business Objects can create a flexible IT organization that can evolve with changing corporate strategies in today\u27s competitive markets. The analysis section completes a SWOT analysis and reviews business strategy, organizational strategy and IT strategy. The analysis concludes that increased legislated process and broad geographic reach in a truly flexible IT organization are not feasible. However, action can be taken to balance control and flexibility that will make IT an enabler for the business. Recommendations include appointment of a CIO, hybrid organizational structure and establishment of performance metrics. As part of implementation strategy, a gradual change management approach is recommended with a dedicated team to monitor progress and adapt the plan as the environment evolves