Progetto finanziato dal Swiss National Science Foundation per lo studio filogenetico della flora sardo-corsa e le conseguenti implicazioni paelogeografiche, paleoclimatiche e biogeografiche

ABSTRACT

Dating the origins of plants endemic to the Corso-Sardinian microplate: A window on the biogeography of the western Mediterranean basin

Collaborators : Salvatore Cozzolino (University of Naples); Gianluigi Bacchetta (University of Cagliari); Massimo Bigazzi (University of Florence); John Thompson, (CNRS/ Montpellier); Josep Rosselló (University of Valencia); Susana Magallon (Universidad Nacional Autonoma de Mexico), Gideon Rosenbaum (University of Mainz)

Key Words: Mediterranean biodiversity; molecular dating; fossils; event-based biogeography; paleogeology; paleoclimate reconstruction; endemism

Main questions : 1) Where did Corso-Sardinian (C-S) endemic plants come from? 2) When did they reach the C-S microplate? 3) How did they reach the C-S microplate, through vicariance, land bridges, or over-water dispersal? 4) Can we identify congruence between geologic and biotic sequences of events? 5) Can we identify congruent biogeographic patterns among several endemic taxa? 6) Can we draw general conclusions about the temporal and spatial sequence of assembly for C-S endemic plants, and the likely paleogeologic and paleoclimatic conditions that might have played a pivotal role in the biogeographic history of the C-S endemic flora?
In this new project, we will apply for the first time a combined molecular phylogenetic, biogeographic, and dating approach to elucidate the time frame for the evolution of plant diversity and biogeographic connections in the Mediterranean basin. We are focusing on Corsica and Sardinia, the two largest islands of the W Mediterranean, because the well known geologic history of the Corso-Sardinian microplate (marked by its Late Oligocene link to NE Spain and S France and Miocene/Pleistocene land bridges with W Italy) provides the necessary framework for reconstructing the biogeographic links of these two islands. Corsica and Sardinia, moreover, have been identified as one of the areas with highest species richness in the Mediterranean, hence they play a key role for understanding Mediterranean biodiversity. "To address these questions, we will reconstruct and date the phylogenies of the genera containing the following initial set of Corso-Sardinian endemics:
Ruta corsica (Rutaceae), Anchusa capellii, A. crispa, A. littorea, A. sardoa, Borago pygmaea, B. morisiana (Boraginaceae), Arum pictum, Biarum dispar, Helicodiceros muscivorus (Araceae), Lavatera plazzae (Malvaceae), Barbarea rupicola, Morisia monanthos (Brassicaceae; international collaborative research funded by the Swiss National Science Foundation)" (Symposium on Mediterranean biogeography at the International Botanical Congress, Vienna 2005)

Links

Institut fur Systematische Botanik und Botanischer Garten