Efecto de transformacion de paisajes sobre la estructuracion genetica de poblaciones de rodriguezia granadensis rchb.f. (orchidaceae), una especie con polimorfismo floral y sistema de polinizacion con recompensa difusa.

The plant family Orchidaceae is one of the most diverse, comprising approximately 25000 - 30000 species. This tremendous diversity is likely a consequence of the diverse and specialized pollinator interactions, making the family one of the most evolutionary derived clades of flowering plants. Colombia is one of the most orchidrich countries in the world, with over 4,200 species registered, however many of these species are under threat in their natural populations due to habitat transformation, and illegal collecting from the wild. a particularly intriguing subgroup of pollinator interactions involves the so-called deceptive pollination, whereby the pollinator species receives no reward for the visits it makes to the flowers, and thus its pollination services. This phenomenon, first described by Darwin two centuries ago, and estimated to occur in approximately one third of orchid species, continues to fascinate biologists studying the evolutionary origins and maintenance of the pollinator interactions, and their contribution to the origin of the species diversity of the family. Once a pollinator has visited a flower in which it has not found a reward, it is likely to avoid further visits to similar flowers, and / or depart from the patch of flowers in which it finds itself. However, floral polymorphism in orchid populations may counteract pollinator departure. This dynamic promotes outcrossing in orchid populations, and is thought to partly explain the small, hyper-dispersed populations commonly found in orchids. as such, small, hyper-dispersed populations may be essential to the persistence of orchid species presenting food-deceptive pollination systems, as due to deception-avoiding tactics of the pollinator, pollination may be unlikely to occur ´in-patch´. However, in the face of habitat fragmentation these small populations are at increased risk of extinction in a metapopulation dynamic, thus putting at risk the survival of the species itself. In Colombia many orchid species are under threat in their natural habitats. This project aims to understand the interaction between landscape composition, and population dynamics and reproductive biology by studying the underlying genetic structure in the orchid species, Rodriguezia granadensis, a small twig epiphyte pollinated by Euglossine bees. Previous studies by members of the research group have revealed polymorphism in pollination rewards, from zero to very little, and weak nectar, making it an ideal model species to study the evolutionary ecology of deceptive pollination, as well as the impact that habitat fragmentation will have on the persistence of orchid species with this type of pollination biology. as such, this study using R. granadensis, will provide essential knowledge to design effective conservation strategies for this important plant biodiversity in Colombia, and more widely in the Neo-tropical region in the face of contemporary landscape transformation.