Do endemic species always have a low competitive ability? A test for two Mediterranean plant species under controlled conditions

Abstract

Many observations concerning biological and ecological differentiation between narrow endemic and widespread congeneric plant species suggest that narrow endemic species are constrained to colonize marginal habitats because of a low tolerance to competition. Despite this topic being an important issue both for understanding evolutionary processes leading to endemism and for conservation purposes, few studies have been performed to compare competitive abilities between endemic and widespread species. Here, we present two independent experiments performed under controlled conditions using two different pairs of endemic and widespread congeneric species: Centaurea corymbosa/Centaurea maculosa and Arenaria provincialis/Arenaria serpyllifolia, both endemic species occurring in rocky calcareous habitats.