The relationship between fleshy-fruited plants and their vertebrate seed dispersal agents often has been depicted as subject to important interannual variation, but no study has thus far documented such variation on a long-term basis. This paper presents the results of a 12-yr investigation on fleshy-fruited plants and avian frugivores in a Mediterranean montane locality of southeastern Spain. The main objective was to document patterns and correlates of long-term variation in the composition and abundance of fruits and birds, with particular reference to seed dispersers. During October-December (''autumn'' period) 1978, abundance of ripe fruits and birds was assessed in a 4-ha plot in dense, well-preserved sclerophyllous scrub, by means of counts in permanent plots and mist-netting, respectively. Diet composition and fruit preference patterns of Erithacus rubecula and Sylvia atricapilla, the two most abundant seed dispersers, were also investigated over the same period, using fecal sample analyses. Possible consequences to the birds of annual variation in fruit supply and diet composition were investigated using data on fat deposition levels and recapture rates of mist-netted individuals.Total fruit abundance (i.e., mean ripe fruit density of all species combined) fluctuated among years between 5.4 Ϯ 11.1 fruits/m 2 (mean Ϯ 1 SD; 1986) and 77.1 Ϯ 78.0 fruits/m 2 (1989) and was positively related to the amount of rainfall in the preceding spring. Not all fruiting species bore ripe fruits every year, and among those species that did, fruit density fluctuated asynchronously and to variable degrees. Seven out of 13 species exhibited significant supra-annual periodicity in fruit abundance, with fluctuation periods ranging from 2 to 6 yr. Variation in the abundance of each of the six most abundant fruit species was unrelated to annual variation in rainfall. The autumn bird assemblage at the study site was made up of year-round resident species (54.1% of captures, all years combined) that were largely fruit predators (feeding on pulp or seeds without performing dispersal) and of autumn-winter resident species (45.5% of captures) that were largely seed dispersers. Bird abundance, all species combined, ranged between 27.1 and 61.5 captures/100 net-hours for 1987 and 1986, respectively. Depending on year, seed dispersers made up 25.6-75.4% of the total captures, and fruit predators made up 20.9-69.7%. The relative importance of nonfrugivores was always negligible (1.1-9.9%). No correlation existed across years between total fruit abundance and the capture rates of all bird species combined, seed dispersers, or fruit predators. Annual variation in the abundance of seed dispersers was positively related to November mean maximum temperature. At the individual species level, S. atricapilla capture rates were correlated with the abundance of the fruits of Phillyrea latifolia, a species exhibiting extreme annual fluctuations.Annual variation in the importance of fruits in the diet of S. atricapilla and E. rubecula was not signi...
L’œuvre d’Emmanuel Lévy représente l’une des tentatives les plus systémati-ques pour construire une théorie du socialisme juridique. En effet, cet auteur est le seul représentant de ce courant à faire œuvre de doctrine dans les Fa-cultés de droit, qui plus est, en droit privé. Toutefois, il s’agit d’une pensée qui s’inscrit dans une histoire à la fois du socialisme juridique et de la politique réformiste du socialisme français autour de 1900. C’est ainsi que d’autres vi-sions socialistes du droit se développent, ceci entre deux pôles extrêmes : l’éthique et l’instrumental. Dans cet article, deux objectifs sont poursuivis : d’une part, cerner les principaux traits du mouvement ; d’autre part, souligner l’apport original d’Emmanuel Lévy à l’intérieur de ce mouvement.
Este trabajo se propone analizar la experiencia política que encabezara Dardo Cúneo (1914-2011) durante el segundo gobierno de Perón. Activo organizador de las actividades intelectuales del PS, admirado por su pluma y considerado como una de las jóvenes promesas del Partido, es sin embargo expulsado a fines de 1952, tras fundar un nuevo periódico, Cúneo se consagrará poco después a la organización de un grupo, Acción Socialista. Inspirándose en la Sociedad Fabiana, es como centro de estudios que busca influir en la acción y en el programa del socialismo. La experiencia fracasará rápidamente, cuando el grupo intentará transformarse en partido, pero representa en esos años uno de los intentos más originales de dar respuesta a la cuestión de una fuerza alternativa de izquierda, sin reproducir la forma partido.
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