The high elevation grassland ecosystem of the Northern Andes, known as páramo, is the most diverse ecosystem of the high elevations of the world, and is an ideal system to understand how species arise and adapt. The goal of this project is to understand the mechanisms of speciation in the páramos and to explore the impacts of climate change on the geographic distribution of species. This will be accomplished using molecular techniques combined with geographic information systems for a dramatic radiation of 140 species of frailejones (plants related to sunflowers) of the páramos, which provide a potential model system for investigating these phenomena. Results from this project will enable a better understanding of rapid speciation processes as well as possible outcomes under different scenarios of climate change. This knowledge will inform conservation and management decisions for the South American páramos and policy development by local authorities. The project will develop tools and methodologies that can be applied in other endangered habitats and species. A public website will be developed and a key to species will also be available on DVD. The project will strengthen multinational collaborations and will train undergraduates at the home institution as well as several visiting researchers.
The páramos and high Andean forests of the tropical Andes are largely dominated by striking plants called frailejones that belong to the sunflower family (Asteraceae). These plants, critically endangered by land-use practices and climate change, are ecologically and culturally essential for ecosystems and local inhabitants. Therefore they are a top priority for research and conservation by government and conservation organizations. As part of a study of the phylogenetic and biogeographic relationships of the group, a thorough revision of the nomenclature was needed as a first step. The most current list of taxa was prepared as part of this project, along with some notes and Spanish names. The list includes various proposed changes in the taxonomy as well as new records for Colombia, and was published in a free-access journal. A website with information, a gallery of photographs, distribution maps and an interactive digital key (available online at http://espeletia.org/) was also built. Previous attempts to reconstruct the evolutionary history of this group failed to resolve relationships among genera and species. This study used multiple molecular markers from two lines of evidence (DNA sequence and fragment data) to reconstruct the evolution of frailejones species. Results provide insightful information about origin, tempo and mode of evolution, suggesting that this has been a case of a very recent rapid radiation, strongly influenced by the complex geography of the tropical Andes. Like the rapidly shrinking páramos, frailejones are highly threatened by climate change, among other factors. Potential changes in species’ geographic distributions under different scenarios of climate change were estimated. In total, future distributions for 133 species were modeled using 23 global climate models under three emissions scenarios for the years 1990 to 2080. Future distributions of frailejones differ considerably between scenarios and global climate models. However, main trends were identified, and a model of explanatory variables was proposed. Most of the species (61-86%) are predicted to experience a reduction in suitable area, with fragmentation and simplification (or extinction) of their populations over time. Species at the extremes of the elevation gradient will suffer the most drastic effects, either increasing or decreasing their suitable areas, with the first extinctions predicted to occur as early as 2020. Overall, an extinction rate of 31-57% is estimated for frailejones species by 2080. Two hotspots with high frequency of predicted extinctions are also identified. These predictions of ecological niche under global climate change will serve as support for studies and proposals of conservation and management of the South American páramos, and for policy formulation by local authorities. This project involved the collaboration of students and colleagues in several institutions in the USA (Saint Louis University, Missouri Botanical Garden, Smithsonian Institution), Colombia (Herbario Nacional, Universidad de los Andes de Bogotá), Venezuela (Universidad de los Andes de Mérida) and Czech Republic (Charles University). In addition to the co-PI, a total of four graduate and eight undergraduate students participated in this project. Results from this project have been presented in 28 conference presentations, one journal publication and a website (http://espeletia.org/). Additional journal publications are forthcoming.
