Erythrina – Evolution of polination systems
I am interested in using phylogenetic patterns to investigate ecological and evolutionary hypotheses, and to study the significance and effects of evolutionary processes, such as hybridization, polyploidy, and reproductive biology. The legumes are a morphologically variable group of plants which exhibit a diversity of pollination systems. The genus Erythrina, for example, with its two modes of pollination, by hummingbirds (photo #2) and perching birds (photo #1) clearly illustrates the morphological diversity encountered within the Leguminosae. By comparing phylogenetic analyses derived from mophological and molecular characters, we have been able to determine the evolutionary history of changes in pollination systems within the genus. These studies indicate that there have been several switches from perching bird to hummingbird pollination in Erythrina, each event implying a complete switch not only in floral morphology (compare photos), but also in floral nectar composition. These conclusions could only have been obtained using the comparative approach in a phylogenetic context as we have done here.
- Vincent Chao, Spéciation et évolution de la pollinisation chez Erythrina