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Triple radiation in the genus Helianthenum: Analysis of the diversification patterns from a micro and macroevolutionary perspective

Sara Martín Hernanz. University of Seville. Supervisors: Abelardo Aparicio & Rafael Albaladejo. Start in 2016.
Summary:
Visualizing phylogenetic relationships among taxa is central to understand radiation and diversification patterns as well as to reconstruct the evolution of traits. The genus Helianthemum, whose centre of diversity is located in the Western Mediterranean area, is the most diverse and widespread in the Cistaceae ranging from Macaronesia to central Asia throughout the Mediterranean, Saharo-Arabian e Irano-Turanian Floristic Regions inhabiting a diversity of habitats from subtropical xerophytic to alpine environments on limestone, chalks, dolomite, gypsum, or saline and sandy soils. The species varies in life form and flower traits intimately related to the mate and breeding system (from gametophytic selfincompatibility to complete selfing by cleistogamy) and its complex systematic and taxonomy is supposedly due to current events of hybridization, convergence and local adaptation. This project has four main complementary objectives: (i) to disentangle the phylogenetic relationships within the clade Helianthemum (above 100 species throughout the Old World), (ii) to assess microevolutionary processes currently involved in the diversification and radiation processes of this bulk of species, (iii) to evaluate the evolution of the reproductive systems in this lineage and (iv) to reconstruct the biogeographic history of the genus along all its distribution range. To this aim we will use Genotyping by Sequencing markers, which may be powerful to disentangle phylogenetic relationships in groups recently radiated or reproductively interconnected.