domingo, 10 de agosto de 2014
Meta bourneti VS Meta menardi
En 2012 se proclamó como araña europea del año a Meta menardi (Latreille, 1804), y se realizaron multitud de trabajos y estudios en cavidades de toda europa, incluida España.
Recientemente, los doctores Stefano Mammola y Marco Isaia han publicado un trabajo en la revista INTERNATIONAL JOURNAL OF SPELEOLOGY de la International Union of Speleology, titulado "Niche differentiation in Meta bourneti and M. menardi (Araneae, Tetragnathidae) with notes on the life history".
Desde este blog aconsejamos a todos los amantes de los invertebrados de cuevas y a aquellos que intentan identificar ambas especies en sus cuevas, que lean detenidamente este trabajo tan interesante. A continuación os ponemos el enlace para descargar el trabajo completo y el resumen en inglés:
Meta menardi and M. bourneti are two species of spiders inhabiting caves and other subterranean habitats. The occurrence of both species within the same cave has never been proved convincingly and several authors hypothesized a complete niche differentiation mainly based on microclimatic conditions.In order to study the apparent niche differentiation of the two species, we studied several populations of M. menardi and M. bourneti occurring in six caves in the Western Italian Alps (NW Italy). A series of squared plots were monitored monthly from March 2012 to February 2013. At each survey, we counted individuals and we collected the main environmental variables at each plot, namely distance from cave entrance, structural typology (wall, floor or ceiling), light intensity, wind speed and counts of potential prey. Moreover, temperature and relative humidity were continuously logged in each cave. We run several statistical models (GLMMs) in order to relate the counts of individuals to the environmental parameters. The distance from the cave entrance, structural typology and prey availability resulted most important factors driving the abundance of both species within the cave. On the other hand, despite life cycles appeared very similar, the two species seems to exhibit different tolerance to the microclimatic variations within the cave, which emerged as the main factors determining the differentiation of their niche. At least in our study area, M. bourneti tolerates broad microclimatic fluctuations and is potentially able to colonize a wide variety of caves. On the other hand, when the climatic conditions in a cave are suitable for M. menardi (narrow ranges of relatively low temperature and high humidity), M. bourneti is excluded.
Fascinante trabajo y desde aquí darle la enhorabuena a los autores del mismo.
Imagen extraído del trabajo citado.