Create your own conference schedule! Click here for full instructions

Abstract Detail

Systematics Section/ASPT

Jara, Orlando A. [1], Madriñán, Santiago [2].

Linking the Andean orogeny and climatic fluctuations with the origin and diversification of begonias having a horned fruit.

The tropical Andes constitute one of the biodiversity hotspot of the world, with near 15 % of all plant species. However, the process that have generate the assemblage of their biota remain poorly known. Molecular phylogenies accompanied by detailed taxonomic work, have proved usefull in detecting biogeographical patters and process in the Andes. Nevertheless, there still remains a high degree of uncertainly about the role that orogeny and the climatic changes during the Pleistocene have played in the diversification of the biota in the Andes. One hypothesis is that ancestral species inhabited the lowland or proto-Andean mountains, and through a process of passive displacement and allopatric speciation the actual patterns of diversity and species distribution emerged. On the other hand, it has been frequently claimed that the formation of Andean biota was essentially a process of colonization or long distance dispersal from lowlands to highlands, and consequently not maintaining synchrony with the Andean formation. Additionally, the climatic fluctuations duringin the Pleistocene has been considered as another possible factor that has influenced the actual diversity and distribution of organisms. In fact, there is evidence of a downward displacement of the vegetation belts of ca. 1000 m during the last maximum glacial in the Eastern Cordillera of Colombia. The consequence of these climatic and biotic dynamics may be evidenced on the highland species, these that could have descended and spread their distribution during glacial periods. After each glaciation the species return to the highlands, generating geographic isolation in distinct mountains and possibly undergoing speciation. In order to provide key evidence to support one or another hypotheses, we will perform an ultrametric phylogeny and a taxonomic revision of the sections Casparya and Semibegoniella (Begonia, Begoniaceae). This is a likely monophylletic clade of near 45 species, distributed from Peru to Costa Rica along the Andean Cordillera, from 500 to 3700 m elevation, and morphologically characterized by the horn shaped fruits. For this purpose, we have been studying the Colombian herbarium specimens and collecting silica-dried samples in Colombia. The DNA sequences to be obtained will include several chloroplast regions and nuclear ribosomal ITS as used in previous studies in Begonia.

Broader Impacts:

Log in to add this item to your schedule

Related Links:
Laboratorio de Botánica y Sistemática

1 - Universidad de los Andes, Laboratorio de Botánica y Systemática, Apartado Aéreo 4976, Bogotá, DC, 00001, Colombia
2 - Universidad de los Andes, Laboratorio de Botánica y Sistemática, Apartado Aéreo 4976, Bogotá, DC, 00001, Colombia


Presentation Type: Poster:Posters for Sections
Session: P
Location: Grand Salon A - D/Riverside Hilton
Date: Monday, July 29th, 2013
Time: 5:30 PM
Number: PSY031
Abstract ID:424
Candidate for Awards:None

Copyright © 2000-2012, Botanical Society of America. All rights reserved