The Maya wall paintings from Chajul, Guatemala

The recent renovation of a house in Chajul in western Guatemala has revealed an unparalleled set of wall paintings, most probably from the Colonial period (AD 1524-1821). The iconography of the murals combines pre-Columbian elements with imported European components in a domestic rather than a religious setting, making them a unique example of Colonial-period art. Here, the authors present the results of iconographic, chemical and radiocarbon analyses of the Chajul house paintings. Dating to the seventeenth to eighteenth centuries AD, the paintings may be connected to a revival of the local religious organisations (cofradías) in the context of waning Spanish colonial control

Allelopathy of Bracken Fern (Pteridium arachnoideum): New Evidence from Green Fronds, Litter, and Soil

The neotropical bracken fern Pteridium arachnoideum (Kaulf.) Maxon. (Dennstaedtiaceae) is described as an aggressive pioneer plant species. It invades abandoned or newly burned areas and represents a management challenge at these invaded sites. Native to the Atlantic Forest and Cerrado (Tropical Savanna) Brazilian biomes, P. arachnoideum has nevertheless become very problematic in these conservation hotspots. Despite some reports suggesting a possible role of allelopathy in this plant’s dominance, until now there has been little evidence of isolated and individually identified compounds with phytotoxic activities present in its tissues or in the surrounding environment. Thus, the aim of this study was to investigate the allelopathic potential of P. arachnoideum by isolating and identifying any secondary metabolites with phytotoxic activity in its tissues, litter, and soil. Bioguided phytochemical investigation led to the isolation and identification of the proanthocyanidin selligueain A as the major secondary compound in the green fronds and litter of this fern. It is produced by P. arachnoideum in its green fronds, remains unaltered during the senescence process, and is the major secondary compound present in litter. Selligueain A showed phytotoxic activity against the selected target species sesame (Sesamum indicum) early development. In particular, the compound inhibited root and stem growth, and root metaxylem cell size but did not affect chlorophyll content. This compound can be considered as an allelochemical because it is present in the soil under P. arachnoideum patches as one of the major compounds in the soil solution. This is the first report of the presence of selligueain A in any member of the Dennstaedtiaceae family and the first time an isolated and identified allelochemical produced by members of the Pteridium species complex has been described. This evidence of selligueain A as a putative allelochemical of P. arachnoideum reinforces the role of allelopathy in the dominance processes of this plant in the areas where it occurs

El Museo Nacional Mexicano

Sobre el origen y desarrollo del Museo Nacional Mexicano. En las raíces de culturas antiguas mexicanas.Área de Historia del Art

Una máscara olmeca en el Templo Mayor de Tenochtitlan

En este artículo se hace una descripción de una máscara olmeca hallada en una ofrenda en las excavaciones del Templo Mayor, sobre sus medidas y su posible procedencia.\ua

El retorno de los dioses. La Coatlicue y la Piedra del Sol

En relación con los hallazgos de las piedras la Coatlicue y del Sol, los escritos de Antonio de León y Gama y su vínculos con el virrey novohispano Manuel Flores y la expedición Malaspina.Área de Historia del Art