Un modelo de la historia de la vegetación de la Cordillera de La Costa de Chile central-sur: la hipótesis glacial de Darwin

Phylogenetic Relationships Among Chilean Species of Drimys (Wtnteraceae) Based on Its Sequences and Insertion/Deletion Events

“…It should be noted that our results showing an early divergence for D. confertifolia are concordant with the view of Smith (1943), who indicated that D. confertifolia is an ancestral species, based on its high number of ovules, a character that was considered by that author as primitive within the group. Smith (1943) and Ehrendorfer et al (1979) (Barreda 1997, Doyle 2000, although, in Chile the pollen record of Drimys dates only from the Quaternary (Heusser 1981, Heusser et al 1999, Villagrán 2001) when the maximum elevation of Andean Mountains already existed (Solbrig et al 1977). Thus, it is presumed that the species of Drimys distributed on the western side of the Andes would be of more recent origin.…”

“…Both Ehrendorfer et al (1979) and Smith (1943) considered both taxa (D. andina and D. winteri) to have differentiated due to the uplift of the Andean Mountains. Recently, principally based on morphology, geographical distribution, and ecology, D. andina has been considered a distinct species (Rodríguez & Quezada 1991, 2001. Phenetic analyses of the distribution of flavonoid compounds have shown that D. andina has the most distinct array of flavonoid constituents.…”

A hybrid zone of two toad sister species, Rhinella atacamensis and R. arunco (Anura: Bufonidae), defined by a consistent altitudinal segregation in watersheds

“…In Chile, the changes in the distribution of the flora due to the climatic fluctuations produced by the Pleistocene glaciers and during the Holocene are well known (Villagrán & Hinojosa 1997, Villagrán et al 1998, Villagrán 2001. Due to the geographic conformation of the countr y, vegetation displacements have mostly been north and south.…”

“…However, these changes were modified by the geographical relief, thus these displacements have reached dif ferent latitudes depending upon their altitude. Thus the Mediterranean vegetation (mainly sclerophyllous shr ubland) reached a lower latitude in the last glacial maximum, mainly in the coastal zone (Villagrán 1995, 2001, Villagrán & Armesto 2005. Considering that R. arunco is an endemic species of the Mediterranean ecoregion (central Chile), the northward expansions of the Mediterranean vegetation during the glacial cycles of the Pleistocene may explain the presence of this species mainly in the coast between 31°30' and 32°30' S (Fig.…”

Patrones de distribución de los geométridos de la Región del Biobío, Chile: Una aproximación para su conservación

“…Gran parte de ellos presentan problemas serios de conser vación, dado la alteración de sus hábitats originales por la acción antrópica (Glade 1993, Armesto et al 1996. Los actuales parches de vegetación se generaron durante el último ciclo glacialinterglacial, los cuales sirvieron no solo como refugio glaciar sino también como reservorio y posterior centro de dispersión de especies (Villagrán 2001). Por la importancia de estos fenómenos en el patrón actual de distribución del bosque templado, la región de Chile central (entre los 29º y los 40º S) ha sido catalogada como uno de los hotspots de biodiversidad a nivel mundial, con 3429 especies vegetales y 335 especies de vertebrados (Myers et al 2000).…”