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While many cases in which conflict over the evolution of social behavior exists even between closely related individuals (e.g., parent-offspring conflict) have been pointed out, little attention has been paid on the problem of where such conflict should lead. A general theory of conflict resolution, however, has recently been developed. The key idea of the theory is the incorporation of conflict costs in the inclusive fitness evaluation. The theory shows that if both sides engaged in the conflict can potentially control the other at a cost, the coevolutionary game of escalating the fight with increased conflict costs always leads either side to give in to the other, resolving the conflict. Here we examine the logical basis of the theory in terms of a simplest example, donor-recipient conflict over the evolution of altruism, and to show its different types of application we review two more specific examples: reproductive-worker conflict over true (sterile) worker evolution in termites and insider-outsider conflict over group size determination. The latter exemplifies the resolution of conflict over the value of a variable (group size in this case) rather than a behavior, suggesting extended applicability of the basic theory.  相似文献   
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Following four hypotheses on the production of soldiers were tested in thePheidole fervida colonies collected in the natural field:
1.  The proportion of new soldiers is primarily dependent on the population size of old workers.
2.  The abundance of old soldiers reduces the proportion of new soldiers.
3.  The production of sexuals reduces the proportion of new soldiers.
4.  The number of soldiers is correlated with the size of defense zone.
The present test suggested that the last idea was most likely to the wild colonies ofP. fervida.  相似文献   
3.
ObjectivesThis study explores the attitudes of physicians-in-training toward older patients. Specifically, we examine why, despite increasing exposure to geriatrics in medical school curricula, medical students and residents continue to have negative attitudes toward caring for older patients.MethodsThis study used ethnography, a technique used by anthropologists that includes participant-observation, semi-structured interviews, and facilitated group discussions. Research was conducted at two tertiary-care academic hospitals in urban Northern California, and focused on eliciting the opinions, beliefs, and practices of physicians-in-training toward geriatrics.ResultsWe found that the majority of physicians-in-training in this study expressed a mix of positive and negative views about caring for older patients. We argue that physicians-in-trainings' attitudes toward older patients are shaped by a number of heterogeneous and frequently conflicting factors, including both the formal and so-called “hidden” curricula in medical education, institutional demands on physicians to encourage speed and efficiency of care, and portrayals of the process of aging as simultaneously as a “problem” of inevitable biological decay and an opportunity for medical intervention.DiscussionEfforts to educate medical students and residents about appropriate geriatric care tend to reproduce the paradoxes and uncertainties surrounding aging in biomedicine. These ambiguities contribute to the tendency of physicians-in-training to develop moralizing attitudes about older patients and other patient groups labeled “frustrating” or “boring”.  相似文献   
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Reproductive behaviors related to habitat utilization were studied in males of the damsefly,Mnais nawai, which has two male forms, territorial orange-winged males (nawai) and non-territorial pale-orange-winged males (sahoi), at the upper part of a mountain stream where they partiallycoexist with a related species,Mnais pruinosa, which also has two male forms, territorial orange-winged males (esakii) and non-territorial hyaline-winged males (strigata). These two species showed parapatric distribution; the lower part of the stream was occupied byM. nawai, and the upper part byM. pruinosa. In the present study, cross-matings occurred between bothMnais species, although normal intraspecific matings occurred more frequently than cross-matings. Territorial males of both species copulated with conspecific females that entered their territory and guarded the ovipositing females, probably to avoid sperm displacement resulting from subsequent copulations. Severe competition for oviposition sites by territorial males even occurred between the two species. On the other hand, non-territorial males of both species have alternative mating strategies (including several tactics such as sneaking, takeover and interception). The possible benefits from conflict among territorial males of both species is discussed.  相似文献   
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