La educación física en el movimiento renacentista europeo del siglo XVI : análisis de la obra 'Positions' de Richard Mulcaster.

Expone una obra de máximo interés para la historia de la educación física: el libro Positions de Rihard Mulcaser. Reflexiona sobre la aportación que supone esta obra a la comprensión de los fenómenos que se valoran y analizan desde la práctica real de la educación física, así como desde las modernas teorías de la motricidad. Realiza una perfecta simbiosis de las claves de la ciencia médica clásica y los principios pedagógicos de su época; en algunos casos incluso revolucionarios e innovadores para el ambiente imperante. El libro Positions contribuyó en gran medida al redescubrimiento del cuerpo humano en el renacimiento. Apoyándose en las enseñanzas de la gimnasia médica de galeno, trato de impulsar las prácticas corporales de los escolares, y también de cualquier persona en los ámbitos no formales, buscando especialmente el mantenimiento y la pontenciación de la salud. Como primer paso empieza por traducir la obra Positions, escrita en un inglés del siglo XVI, para desde ahí ordenar y sistematizar las ideas de Mulcaser y así poder llevar a cabo un estudio comparativo con una perspectiva evolutiva en el campo de las ciencias de la motricidad humana. En definitiva, el autor de Positions pone en acento el aspecto preventivo del ejercicio, y no tanto en el terapéutico. La principal preocupación es la modificación de los malos hábitos de salud de los ciudadanos y la creación de estilos de vida activos desde la primera infancia. De este modo, aunque su tratado va dirigido a toda clase de individuos, los que más preocupan son los sedentarios y, entre ellos, los estudiantes. La obra no manifiesta una visión de la salud exclusivamente higiénica o profiláctica, también aparece la dimensión educativa porque en ella se reclama la colaboración de los padres, vecinos y maestros a la hora de velar por la salud del niño, en vez de dejarla en manos de los médicos.

Evaluation of cacao (Theobroma cacao L.) clones against seven Colombian isolates of Moniliophthora roreri (Cif.) Evans et al., representing four major genetic groupings of the pathogen in cacao

Artificial pod inoculation was used to compare the relative aggressiveness of seven Colombian isolates of Moniliophthora roreri (the causal agent of moniliasis or frosty pod disease), representing four major genetic groupings of the pathogen in cacao (cocoa), when applied to five diverse cacao genotypes (ICS-1, ICS-95, TSH-565, SCC-61 and CAP-34) at La Suiza Experimental Farm, Santander Department, Colombia. The following variables were evaluated 9 weeks after inoculation of 2- to 3-month-old pods with spore suspensions (1.2 x 10(5) spores mL(-1)): (i) disease incidence (DI); (ii) external severity (ES); and (iii) internal severity (IS). IS was found to be of greatest value in classifying the reaction of the host genotype against M. roreri. Genetic variation reported between isolates and cacao genotypes was not matched by similar diversity in their aggressiveness. All isolates were generally highly aggressive against most cacao genotypes, with only two isolates showing reduced IS and ES reactions. There was considerable variation between clones in the IS and ES scores, but one cultivated clone (ICS-95) displayed a significant level of resistance against all seven isolates. This clone may be useful in cacao breeding initiatives for resistance to moniliasis of cacao.

The evolution of maximum body size of terrestrial mammals

The extinction of dinosaurs at the Cretaceous/Paleogene (K/Pg) boundary was the seminal event that opened the door for the subsequent diversification of terrestrial mammals. Our compilation of maximum body size at the ordinal level by sub-epoch shows a near-exponential increase after the K/Pg. On each continent, the maximum size of mammals leveled off after 40 million years ago and thereafter remained approximately constant. There was remarkable congruence in the rate, trajectory, and upper limit across continents, orders, and trophic guilds, despite differences in geological and climatic history, turnover of lineages, and ecological variation. Our analysis suggests that although the primary driver for the evolution of giant mammals was diversification to fill ecological niches, environmental temperature and land area may have ultimately constrained the maximum size achieved.

Richard le Scandinave? Héroïsme et métissage culturel dans le Roman de Rou de Wace

This article explores the bilingual and bicultural identity of Normandy revealed by Wace's depiction of Duke Richard the Fearless in the Roman de Rou. The anecdotes that open the Troisieme Partie of the Rou are analysed in the light of Scandinavian analogues, in particular the Saga of Grettir. This allows us to discern in Wace's stories a dual tradition, with romance and scandinavian strands that were not always mutually compatible, resulting in narrative tensions that had hitherto remained unexplained. In particular, the fearless duke takes on connotations of mental instability that would only have been recognised by the Normans of Danish origin.

The maximum rate of mammal evolution

How fast can a mammal evolve from the size of a mouse to the size of an elephant? Achieving such a large transformation calls for major biological reorganization. Thus, the speed at which this occurs has important implications for extensive faunal changes, including adaptive radiations and recovery from mass extinctions. To quantify the pace of large-scale evolution we developed a metric, clade maximum rate, which represents the maximum evolutionary rate of a trait within a clade. We applied this metric to body mass evolution in mammals over the last 70 million years, during which multiple large evolutionary transitions occurred in oceans and on continents and islands. Our computations suggest that it took a minimum of 1.6, 5.1, and 10 million generations for terrestrial mammal mass to increase 100-, and 1,000-, and 5,000- fold, respectively. Values for whales were down to half the length (i.e., 1.1, 3, and 5 million generations), perhaps due to the reduced mechanical constraints of living in an aquatic environment. When differences in generation time are considered, we find an exponential increase in maximum mammal body mass during the 35 million years following the Cretaceous–Paleogene (K–Pg) extinction event. Our results also indicate a basic asymmetry in macroevolution: very large decreases (such as extreme insular dwarfism) can happen at more than 10 times the rate of increases. Our findings allow more rigorous comparisons of microevolutionary and macroevolutionary patterns and processes. Keywords: haldanes, biological time, scaling, pedomorphosis