XV.—The Fata Morgana

Among optical phenomena which originate over the surface of water there is one so ill-defined and ill-observed as to be still mysterious; till now it has received no valid explanation. The Italians call it the Fata Morgana. Under conditions still lacking precise description, there appear on the far side of the Straits of Messina certain fantastic visions, fortresses and castles of unknown cities, which seem to emerge from the sea, soon to vanish again. These are the "palaces” of the "fairy Morgana,” which appear and disappear at the capricious stroke of the magician's wan

Why do some social insect queens mate with several males? Testing the sex-ratio manipulation hypothesis in Lasius niger

Although multiple mating most likely increases mortality risk for social insect queens and lowers the kin benefits for nonreproductive workers, a significant proportion of hymenopteran queens mate with several males. It has been suggested that queens may mate multiply as a means to manipulate sex ratios to their advantage. Multiple paternity reduces the extreme relatedness value of females for workers, selecting for workers to invest more in males. In populations with female-biased sex ratios, queens heading such male-producing colonies would achieve a higher fitness. We tested this hypothesis in a Swiss and a Swedish population of the ant Lasius niger. There was substantial and consistent variation in queen mating frequency and colony sex allocation within and among populations, but no evidence that workers regulated sex allocation in response to queen mating frequency; the investment in females did not differ among paternity classes. Moreover, population-mean sex ratios were consistently less female biased than expected under worker control and were close to the queen optimum. Queens therefore had no incentive to manipulate sex ratios because their fitness did not depend on the sex ratio of their colony. Thus, we found no evidence that the sex-ratio manipulation theory can explain the evolution and maintenance of multiple mating in L. niger

Un bon exercice de lecture du Cours de linguistique générale

Cet article va rendre compte d’aspects de la transmission de la pensée saussurienne qui ont surgi lors de la préparation et du déroulement (en cours actuellement) d’un séminaire intitulé Reading Saussure and Chomsky. Comme Chomsky n’avait pu lire que le seul CLG, nous prendrons cet ouvrage comme point de repère que nous confronterons aux notes des étudiants, à celles de Saussure ainsi qu’à la Collation Sechehaye (Sofia 2015) récemment parue. Nous prendrons trois passages : les premières lignes du CLG; le fameux circuit de la parole (tous deux dans l’«Introduction» du CLG), et la célèbre comparaison de la langue avec le jeu d’échecs (CLG: 125 et 153) qui avait retenu l’attention de Chomsky. Nous verrons des exemples d’adjonction ou de suppression par rapport aux notes des étudiants, des reformulations qui mettent une meilleure lecture de la pensée saussurienne, ainsi que de+s modifications aux schémas notés par les auditeurs apportés par Bally et Sechehaye. Nousverrons aussi comment Chomsky a choisi de retenir ce qui l’intéressait dans l’œuvre de Saussure, quitte à laisser de côté des aspects qui auraient dû l’interpele

Rendre visible des réalités linguistiques

Cet article se demande comment faire prendre conscience de la manière dont sa langue usuelle fonctionne à des apprenants de langues étrangères pour les amener à apprécier comment les choses se passent dans les langues cibles. L’exemple choisi porte sur l’expression de la politesse notamment à travers les marqueurs grammaticaux, mais aussi l’évaluation des situations et donc des registres à employer.How can one make learners of foreign languages aware of not only the target languages but also their mother tongue work? We have chosen to discuss the expression of politeness through the use of so called ‘polite forms’, but also an evaluation of the type of situation one is dealing with and hence which register would be most appropriate

Las variaciones periódicas de los ventisqueros

El señor Forel, autor de este interesante artículo, al terminarlo, invoca simpatía para los trabajos de la Comisión Internacional de los Ventisqueros, y solicita la colaboración de todos los trabajadores, físicos, naturalistas, alpinistas, ó exploradores de regiones polares, así como el apoyo de las academias y dé los gobiernos, y confía en que este concurso no le faltará. La iniciativa del señor Marshall-Hall ha encontrado eco en este Museo. Desde el primer momento de conocida, hemos procurado reunir todos los antecedentes sobre la cuestión glacial en este extremo de la América, donde tan grandes manifestaciones ha dejado de su paso el hielo y donde los gigantes ventisqueros y neveras de todos los tipos se cuentan por centenares. La acción glacial se ha hecho sentir en toda la extensión del territorio argentino desde el grado 23 hasta el 56, y las facilidades para el estudio de esa acción son grandes por su misma magnitud; además, este estudio tan importante está ligado, é íntimamente, con el de una de las cuestiones geográficas más interesantes de estas regiones: el divortia aquarum continental, producido en buena extensión por esa misma acción. La traducción del artículo del señor Forel, tiene pues su colocación justificada en esta Revista, y el personal técnico del Museo de La Plata va á ser un colaborador entusiasta de la Comisión Internacional de los Ventisqueros, cuyo programa de trabajo publicamos. (Presentación por Francisco P. Moreno)Facultad de Ciencias Naturales y Muse

REVIEW OF EARLY TRIASSIC THYLACOCEPHALA

Thylacocephala (Euarthropoda: Eucrustacea?) is a group of enigmatic fossil euarthropods, known from at least the Silurian to the Cretaceous. The Triassic is considered to be the period during which thylacocephalans were the most diversified with 17 species reported from 19 localities in nine countries. However, Thylacocephala were assumed to be rare during the Early Triassic until recent discoveries in Japan, Nevada and Idaho, U.S.A.       Our study focuses on thylacocephalans from the Early Triassic, especially from Madagascar and Idaho. The revision of previously known taxa from Madagascar provides new important information. A new kind of ornamentation is reported for Paraostenia ambatolokobensis nov. comb., previously assigned to Ostenocaris ambatolokobensis. In addition, Ankitokazocaris acutirostris and Paraostenia ambatolokobensis are only the third and fourth thylacocephalan taxa for which possible cephalic appendages are described.  New occurrences of Thylacocephala in Nevada and Idaho, U.S.A., lead to the description of one new taxon and to the reassignement of Parisicaris triassica to Ankitokazocaris triassica nov. comb. Those occurrences provide a significant contribution to the knowledge of Thylacocephala taxonomic diversity and geographic distribution during the Early Triassic. An important revision of Early Triassic thylacocephalan taxa from Japan and China is also performed, including Ankitokazocaris chaohuensis, Ankitokazocaris parva nov. comb., Ankitokazocaris utatsuensis nov. comb. and Paraostenia sp. Overall, the taxonomic diversity of Triassic thylacocephalans has likely been slightly over-estimated (17 species before, 15 now). However, the Triassic represents the richest period in terms of thylacocephalan-bearing outcrops (19 localities from nine countries)

Biology and conservation of freshwater bivalves : past, present and future perspectives

Freshwater bivalves have been highly threatened by human activities, and recently their global decline has been causing conservational and social concern. In this paper, we review the most important research events in freshwater bivalve biology calling attention to the main scientific achievements. A great bias exists in the research effort, with much more information available for bivalve species belonging to the Unionida in comparison to other groups. The same is true for the origin of these studies, since the publishing pattern does not always correspond to the hotspots of biodiversity but is concentrated in the northern hemisphere mainly in North America, Europe and Russia, with regions such as Africa and Southeast Asia being quite understudied. We also summarize information about past, present and future perspectives concerning the most important research topics that include taxonomy, systematics, anatomy, physiology, ecology and conservation of freshwater bivalves. Finally, we introduce the articles published in this Hydrobiologia special issue related with the International Meeting on Biology and Conservation of Freshwater Bivalves held in 2012 in Braganc¸a, Portugal.We would like to express our gratitude to our sponsors and institutions, especially to the Polytechnic Institute of Braganca for all the logistic support. We acknowledge all keynote speakers, authors, session chairpersons and especially to all attendees whose contributions were fundamental for the success of this meeting. We would also like to thank all referees of this special issue and to Koen Martens, Editor-in-Chief of Hydrobiologia, for all the valuable comments and suggestions. The chronogram was built with the help of the expert opinion of fellow colleagues Rafael Araujo, Arthur Bogan, Kevin Cummings, Dan Graf, Wendell Haag, Karl-Otto Nagel and David Strayer to whom we are very grateful. The authors acknowledge the support provided by Portuguese Foundation for Science and Technology (FCT) and COMPETE funds-projects CONBI (Contract: PTDC/AAC-AMB/117688/2010) and ECO-IAS (Contract: PTDC/AAC-AMB/116685/2010), and by the European Regional Development Fund (ERDF) through the COMPETE, under the project "PEst-C/MAR/LA0015/2011"

A922 Sequential measurement of 1 hour creatinine clearance (1-CRCL) in critically ill patients at risk of acute kidney injury (AKI)

Meeting abstrac

Insetos em presépios e as "formigas vestidas" de Jules Martin (1832-1906): uma curiosa manufatura paulistana do final do século XIX

Encontrados no Brasil desde os primórdios da colonização portuguesa, os presépios logo tiveram de adaptar-se à realidade local, circunstância muito propícia ao aparecimento de concepções heterodoxas e ao emprego de elementos exóticos da fauna e flora de cada região. Como registros envolvendo insetos são muito pouco comuns, chama a atenção que fêmeas de saúva, Atta sp. (Hymenoptera, Formicidae), tenham sido aproveitadas na composição de presépios no estado de São Paulo. Tendo subsistido pelo menos até a década 1960, os "presépios de formigas" existentes em cidades como Embu das Artes poderiam estar relacionados às "formigas vestidas" criadas por Jules Martin, curiosa manufatura paulistana do último quartel do século XIX.Present in Brazil since the beginning of Portuguese colonization, crèche nativity scenes were soon adapted to local reality, a propitious circumstance for the appearance of heterodox conceptions and the use of exotic elements of the fauna and flora peculiar to each region. As records about insects are very uncommon, it is noteworthy that females of leaf-cutting ants, Atta sp. (Hymenoptera, Formicidae), were used to compose crèche nativity scenes in São Paulo State. Having subsisted at least up to the decade of 1960, the "ant crèches" of cities such as Embu das Artes could be related to the then famous "dressed ants" created by Jules Martin, a curious manufacture of the city of São Paulo in the last quarter of the 19th century

A Revision of Malagasy Species of Anochetus Mayr and Odontomachus Latreille (Hymenoptera: Formicidae)

Species inventories are essential for documenting global diversity and generating necessary material for taxonomic study and conservation planning. However, for inventories to be immediately relevant, the taxonomic process must reduce the time to describe and identify specimens. To address these concerns for the inventory of arthropods across the Malagasy region, we present here a collaborative approach to taxonomy where collectors, morphologists and DNA barcoders using cytochrome c oxidase 1 (CO1) participate collectively in a team-driven taxonomic process. We evaluate the role of DNA barcoding as a tool to accelerate species identification and description. This revision is primarily based on arthropod surveys throughout the Malagasy region from 1992 to 2006. The revision is based on morphological and CO1 DNA barcode analysis of 500 individuals. In the region, five species of Anochetus (A