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Social animals regularly face consensus decisions whereby they choose, collectively, between mutually exclusive actions. Such decisions often involve conflicts of interest between group members with respect to preferred action. Conflicts could, in principle, be resolved, either by sharing decisions between members (‘shared decisions’) or by one ‘dominant’ member making decisions on behalf of the whole group (‘unshared decisions’). Both, shared and unshared decisions, have been observed. However, it is unclear as to what favours the evolution of either decision type. Here, after a brief literature review, we present a novel method, involving a combination of self-organizing system and game theory modelling, of investigating the evolution of shared and unshared decisions. We apply the method to decisions on movement direction. We find that both, shared and unshared, decisions can evolve without individuals having a global overview of the group's behaviour or any knowledge about other members' preferences or intentions. Selection favours unshared over shared decisions when conflicts are high relative to grouping benefits, and vice versa. These results differ from those of group decision models relating to activity timings. We attribute this to fundamental differences between collective decisions about modalities that are disjunct (here, space) or continuous (here, time) with respect to costs/benefits. [ABSTRACT FROM AUTHOR]

1. The distribution and density of Eurasian badgers Meles meles in Luxembourg was estimated by gathering information about the location of badger setts with a questionnaire survey, by visiting 708 setts in order to classify them as ‘main setts’ or ‘outliers’, and by estimating social group size by directly counting emerging badgers. 2. Badgers were found to be widely distributed in Luxembourg, with a minimum main sett density of 0.17 setts/km2. Setts were sited preferentially in forest habitat. The mean minimum group size was 4.6 badgers. 3. The Luxembourg badger population was conservatively estimated to contain at least 2010 adult and young badgers (95% CI 1674–2347) in spring 2002, equivalent to a density of 0.78 adult and young badgers/km2 (95% CI 0.65–0.91). This is moderate compared to most of continental Europe. [ABSTRACT FROM AUTHOR]

(1) The Shetland Islands lie between Scotland and Norway and this study describes the vegetation types found there with reference to both British/Continental and Scandinavian communities. (2) A conspectus of the main plant communities was obtained by recording vegetation plots from fifteen of the islands, from shingle beaches, sand dunes, salt-marshes, wet meadows, grasslands, blanket peat and heaths. (3) Sixty-five noda were identified and their general characteristics described. These noda were assigned to both recognized and new taxa within seventeen phytosociological classes. (4) A new association of grazed low altitude blanket bogs, the Empetrum- Rhytidiadelphus loreus Association is outlined. (5) The factors influencing plant and vegetation distribution in Shetland are discussed: geographical position and physical isolation from seed sources provide the historical basis. (6) While climatic and topographic interaction on the flora have determined the natural vegetation communities, the impact of land use, particularly grazing, has been to confine these communities to areas inaccessible to sheep. The majority of Shetland's vegetation composition has been determined by grazing. (7) The absence of comparative taxonomic studies, the Islands' geographical position and climate, the influence of salt-spray and intensive land-use produce a merging of community boundaries and difficulties in delimiting discrete associations. [ABSTRACT FROM AUTHOR]

We report a case of angioedema caused by angiotensin-converting enzyme inhibitor and topical lignocaine spray, administered during nasendoscopy.Angioedema induced by angiotensin-converting enzyme inhibitors is a rare but well known entity. Allergy to topical lignocaine has been acknowledged as a rare phenomenon when used for dental surgery and for skin anaesthesia, but it has not previously been reported after topical administration prior to nasendoscopy. In the reported case, our patient was unfortunate enough to be allergic to both lisinopril and lignocaine. The result was life-threatening airway obstruction, and the continued use of lignocaine spray sustained the laryngeal oedema. We advise that patients are asked about any and every allergy – specifically, any previous problems with dental procedures – before administration of local anaesthetic spray to the upper aerodigestive tract. [ABSTRACT FROM AUTHOR]