Pillon Y. auteur aut IRD Hopkins H.C.F. auteur aut IRD Rigault Frédéric auteur aut IRD Jaffré Tanguy auteur aut IRD Stacy E.E. auteur aut IRD text journalArticle eng text/pdf born digital access The causes of the species richness of tropical trees are poorly understood, in particular the roles of ecological factors such as soil composition. The nickel(Ni)-hyperaccumulating tree genus Geissois (Cunoniaceae) from the South-west Pacific was chosen as a model of diversification on different substrates. Here, we investigated the leaf element compositions, spatial distributions and phylogeny of all species of Geissois occurring on New Caledonia. We found that New Caledonian Geissois descended from a single colonist and diversified relatively quickly into 13 species. Species on ultramafic and nonultramafic substrates showed contrasting patterns of leaf element composition and range overlap. Those on nonultramafic substrates were largely sympatric but had distinct leaf element compositions. By contrast, species on ultramafic substrates showed similar leaf element composition, but occurred in many cases exclusively in allopatry. Further, earlier work showed that at least three out of these seven species use different molecules to bind Ni. Geissois qualifies as a cryptic adaptive radiation, and may be the first such example in a lineage of tropical forest trees. Variation in biochemical strategies for coping with both typical and adverse soil conditions may help to explain the diversification and coexistence of tropical forest trees on similar soil types. specialized ARBRE FORESTIER ESPECE TROPICALE FORET DENSE DISTRIBUTION SPATIALE DIVERSITE SPECIFIQUE PHYLOGENIE ADAPTATION RELATION SOL PLANTE ACCUMULATION ALUMINIUM NICKEL MILIEU INSULAIRE COMPOSITION FOLIAIRE SOL ULTRAMAFIQUE NOUVELLE CALEDONIE 076BOTA05 068PROSOL 202 2 521-530 2014 0028-646X https://www.documentation.ird.fr/hor/fdi:010061540 10.1111/nph.12677 0028-646X [F B010061540] https://www.documentation.ird.fr/hor/fdi:010061540 https://www.documentation.ird.fr/intranet/publi/depot/2014-03-24/010061540.pdf Accès réservé (Intranet de l'IRD) IRD - Base Horizon / Pleins textes 2014-03-24 2022-04-11 fdi:010061540 fre