Can more K-selected species be better invaders? A case study of fruit flies in La Réunion
Invasive species are often said to be r-selected. However, invaders must sometimes compete with related resident species. In this case invaders should present combinations of life-history traits that give them higher competitive ability than residents, even at the expense of lower colonization ability. We test this prediction by comparing life-history traits among four fruit fly species, one endemic and three successive invaders, in La Réunion Island. Recent invaders tend to produce fewer, but larger, juveniles, delay the onset but increase the duration of reproduction, survive longer, and senesce more slowly than earlier ones. These traits are associated with higher ranks in a competitive hierarchy established in a previous study. However, the endemic species, now nearly extinct in the island, is inferior to the other three with respect to both competition and colonization traits, violating the trade-off assumption. Our results overall suggest that the key traits for invasion in this system were those that favoured competition rather than colonization.
Document Type: Research Article
Affiliations: 1: UMR 5175, CNRS Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), 1919 route de Mende, 34293 Montpellier Cedex, France 2: UMR 53 Peuplements Végétaux et Bio-agresseurs en Milieu Tropical CIRAD Pôle de Protection des Plantes (3P), 7 chemin de l’IRAT, 97410 St Pierre, La Réunion, France,
Publication date: 2007-09-01