Effects of fighting decisions on formation and structure of dominance hierarchies

The characteristics of complex social systems often cannot be predicted from exploring individual agonistic interactions in isolation. In a series of models, this study linked the decision-making processes that govern dyadic interactions with the emergent properties of hierarchical structures in social groups. Contrary to the intuitive expectation that resolution of ambiguities in fighting between closely matched opponents effectively promotes the formation of a social hierarchy, engagement in contests with opponents of dissimilar status lead to a faster emergence of hierarchical structures. The increased certainty of outcome in such asymmetric contests both reinforced the previously established dominance, and allowed for an indirect resolution of existing ambiguous relationships. High-return fights also resulted in a more rapid hierarchy formation, while escalating in fights decreased the costs of maintaining hierarchical relationships and increased their stability.     

Periodic electric field as a biopolymer conformation switch: a possible mechanism

A theoretical model is proposed to describe the influence of a periodic electric field (PEF) upon a biopolymer. The biopolymer is treated as a classical mechanical system consisting of subsystems (molecular groups) which interact with each other through potential forces. The PEF is treated as a periodic driving force applied to a molecular group. The energy dissipation is considered using the model of fluid (viscous) friction. Arguments for the non-linear character of the friction-velocity dependence caused by the non-Newtonian rheology of a viscous medium are formulated.A forced molecular-group motion is investigated for the situation of a small driving-force period, with oscillations overdamped and a driving force consisting of more than one harmonic. As a result, it is established that the motion always gets to a terminal stage when only a small-scale vibration about some point, X ^*, takes place. The terminal motion is preceded by a transient characterized by the presence of a directional velocity component and so by a drift along a potential profile. the drift goes on until a barrier is met which has a sufficiently large steepness (the barrier height is not important). As a result, the point X ^* may happen to be remote from the conformation potential local minimum (conformational state). The physical reasons for the drift are described.If we consider the small-scale vibration about X ^* in the framework of the hierarchy of scales for intramolecular mobility, it can be regarded as an equilibrium mobility, whereas the drift can be regarded as a functionally important motion, and X ^* as a new conformational state which is realizable only in the presence of the PEF. It may be concluded, as the result of a consistent treatment and neglecting the small-scale vibration, that the conformational potential is modified by adding a linear term (in the one-dimensional case). In this connection, the set of conformational states can both deform (deviation of the positions of minima and their relative depth) and rearrange qualitatively (some minima can vanish and/or new minima can appear). In particular, the transition from one conformation to another one may happen due to rearrangement.     

A review of criticisms of phylogenetic nomenclature: is taxonomic freedom the fundamental issue?

The proposal to implement a phylogenetic nomenclatural system governed by the PhyloCode), in which taxon names are defined by explicit reference to common descent, has met with strong criticism from some proponents of phylogenetic taxonomy (taxonomy based on the principle of common descent in which only clades and species are recognized). We examine these criticisms and find that some of the perceived problems with phylogenetic nomenclature are based on misconceptions, some are equally true of the current rank-based nomenclatural system, and some will be eliminated by implementation of the PhyloCode. Most of the criticisms are related to an overriding concern that, because the meanings of names are associated with phylogenetic pattern which is subject to change, the adoption of phylogenetic nomenclature will lead to increased instability in the content of taxa. This concern is associated with the fact that, despite the widespread adoption of the view that taxa are historical entities that are conceptualized based on ancestry, many taxonomists also conceptualize taxa based on their content. As a result, critics of phylogenetic nomenclature have argued that taxonomists should be free to emend the content of taxa without constraints imposed by nomenclatural decisions. However, in phylogenetic nomenclature the contents of taxa are determined, not by the taxonomist, but by the combination of the phylogenetic definition of the name and a phylogenetic hypothesis. Because the contents of taxa, once their names are defined, can no longer be freely modified by taxonomists, phylogenetic nomenclature is perceived as limiting taxonomic freedom. We argue that the form of taxonomic freedom inherent to phylogenetic nomenclature is appropriate to phylogenetic taxonomy in which taxa are considered historical entities that are discovered through phylogenetic analysis and are not human constructs.     

Game theory-based stakeholder analysis of marine nature reserves and its case studies in Guangdong Province,China

Marine nature reserves (MNRs) play an important role in biodiversity conservation and ecosystem restoration, which are valuable for marine resource protection in China. Many stakeholders are involved in MNRs. The interactions between MNR managers and other stakeholders affect the effectiveness of MNR management. This work divided MNR stakeholders into three categories and applied the analytical hierarchy process (AHP) to identify the key stakeholders. The game model was set up to analyze the strategies of MNR staff and stakeholders. The situation of key stakeholders and management was studied in two MNRs in Guangdong Province through field research and questionnaires. The results showed that fishermen were the main stakeholders in the two cases. The strategies adopted by MNR staff to improve the efficiency of law enforcement and decrease the probability of illegal activities of fishermen are to increase penalties, improve the arrest rate of illegal activities, and reduce the cost of law enforcement per patrol. We suggested that the fishermen’s negative impacts could be minimized by establishing a market management system to reduce illegal earnings, a record-keeping system to share additional benefits only with the fishermen who comply with the law, and an association mechanism in the coastal province to control illegal fishing across provincial boundaries. Identifying key stakeholders and analyzing their relationships could be helpful to find out the best strategy for different MNRs. Building a community of shared interests among various stakeholders could be a promising way to resolve conflicts and improve management effectiveness in MNRs.     

Hierarchical saturation of soil carbon pools near a natural CO2 spring

Soil has been identified as a possible carbon (C) sink to mitigate increasing atmospheric CO₂ concentration. However, several recent studies have suggested that the potential of soil to sequester C is limited and that soil may become saturated with C under increasing CO₂ levels. To test this concept of soil C saturation, we studied a gley and organic soil at a grassland site near a natural CO₂ spring. Total and aggregate‐associated soil organic C (SOC) concentration showed a significant increase with atmospheric CO₂ concentration. An asymptotic function showed a better fit of SOC and aggregation with CO₂ level than a linear model. There was a shift in allocation of total C from smaller size fractions to the largest aggregate fraction with increasing CO₂ concentration. Litter inputs appeared to be positively related to CO₂ concentration. Based on modeled function parameters and the observed shift in the allocation of the soil C from small to large aggregate‐size classes, we postulate that there is a hierarchy in C saturation across different SOC pools. We conclude that the asymptotic response of SOC concentration at higher CO₂ levels indicates saturation of soil C pools, likely because of a limit to physical protection of SOC.     

An improved approach to evaluate car sharing options

We develop an improved approach to evaluate car sharing options under uncertain environments with the combination of Fuzzy Analytic Hierarchy Process (F-AHP) and Fuzzy Technique for Order Preference by Similarity to Ideal Solution (F-TOPSIS), which consists of three steps. In the first step, we propose a SCUMN (Specific, Comprehensive, Understandable, Measurable, and Neutral) methodology to identify appropriate indicators and obtain a final list of 24 indicators according to their relevance to car sharing options. In the second step, we determine the weight of each indicator with F-AHP and conduct consistency check of the comparison matrix of selected indicators. In the third step, comparison of different options is performed with selected indicators and F-TOPSIS. A case study is provided to validate the proposed approach. Twenty-four indicators are identified to evaluate five different car sharing options and rank them according to their closeness coefficients in decreasing order. And thirty-one sensitivity analysis experiments are conducted to figure out the influence of indicators on decision making. The experimental results show that the proposed approach is capable of evaluating car sharing options with uncertainty and vagueness. F-AHP is able to determine the weight for each selected indicator and F-TOPSIS demonstrates its advantage in comparing potential options.     

Maintenance of dominance is mediated by urinary chemical signals in male European lobsters,Homarus gammarus

We studied the relevance of urine cues in Homarus gammarus dominance maintenance, hypothesising that urinary signals are necessary to mediate recognition of former opponents. Males in size-matched pairs interacted on two consecutive days with or without blocking urine release by adding catheters to both contestants on the second day. European lobsters established dominance in a first fight, and fight duration and aggression levels decreased strongly from first to second day in animals with free urine release, indicating the maintenance of this dominance relationship. If urine was blocked on the second day, fight durations were long in both first and second day interactions. Results demonstrate that urine signals contribute to the maintenance of dominance in H. gammarus males.     

THE PROBLEM OF THE FUTURE WORLD: W.E.B. DU BOIS AND THE RACE CONCEPT AT MIDCENTURY

Most studies of police–minority relations in America focus on blacks, usually in comparison with whites. This pattern is particularly puzzling in light of the growing population of Hispanic Americans throughout the US, now outnumbering blacks and consisting of the majority in some major cities. Aside from the need for more empirical research on the policing of Hispanics per se, comparing Hispanics’ relations with the police to other racial and ethnic groups offers some important insights into both the dimensions that are shared across groups and those that are distinctive to Hispanics. This article critically evaluates the small body of empirical research literature on this topic – highlighting both deficiencies in this literature as well as suggestive findings – and concludes by identifying a set of issues that should be addressed in future studies. The available evidence largely supports a racial-hierarchy perspective with regard to the policing of different racial and ethnic groups in the US.