Résumé
Natural selection is expected to cause convergence of life histories among
taxa as well as correlated evolution of different life-history traits.
Here, we quantify the extent of convergence of five key life-history
traits (adult fire survival, seed storage, degree of sexual dimorphism,
pollination mode, and seed-dispersal mode) and test hypotheses about their
correlated evolution in the genus Leucadendron (Proteaceae) from the
fire-prone South African fynbos. We reconstructed a new molecular
phylogeny of this highly diverse genus that involves more taxa and
molecular markers than previously. This reconstruction identifies new
clades that were not detected by previous molecular study and
morphological classifications. Using this new phylogeny and robust methods
that account for phylogenetic uncertainty, we show that the five
life-history traits studied were labile during the evolutionary history of
the genus. This diversity allowed us to tackle major questions about the
correlated evolution of life-history strategies. We found that species
with longer seed-dispersal distances tended to evolve lower
pollen-dispersal distance, that insect-pollinated species evolved
decreased sexual dimorphism, and that species with a persistent soil
seed-bank evolved toward reduced fire-survival ability of adults.