Genetic structure and population differentiation of the Mediterranean pioneer spiny broom Calicotome villosa across the Strait of Gibraltar

摘要: The region around the Strait of Gibraltar is considered to be one most relevant ‘hot spots’ biodiversity in Mediterranean Basin due its historical, biogeographical, and ecological features. Prominent among these role as a land bridge for migration differentiation species during Pleistocene, consequence lowering sea level climate changes associated with Ice Ages. In present study, we report multilevel hierarchical investigation genetic diversity Calicotome villosa, common pioneer legume shrub, at regional scale. results analysis progeny arrays are consistent predominantly outcrossing mating system all populations analysed. Geographically, pattern population isolation by distance was found, but accounted only approximately 2% among-population differentiation. Consequently, extensive historical gene flow appears rule this area. According natural history traits C. villosa (pollination, dispersal, colonization ability), hypothesize that must strongly influenced seed dispersal because pollen very limited. Based on trade use, cattle human movements across have favoured dispersal. We review discuss compare them those other reported studies phylogenetic Gibraltar. It stressed ability, which depends upon life form, can more critical factor than pollination. © 2008 Linnean Society London, Biological Journal Society, 2008, 93, 39–51.