Fruit diversity in Myrtaceae: ecological and evolutionary hypotheses for the success of this family in the Neotropic.
ampomanesia; Eugenia; Germination; Macroevolution; Myrcia; Psidium
leshy fruits are the link between fauna and flora. They serve as a resource for fauna, while at the same time favoring the colonization of plant species. Selective pressures in plant-animal interactions can shape fruit and seed characters and have the potential to explain current species diversity. In this dissertation, I used Myrtaceae, one of the most species-rich families in the tropics, as a model to test the effect of plant and fruit characters on the family's speciation rates. Thus, in chapter one I expanded the morphological database of Myrtaceae fruits and seeds, resulting in data for 956 species and adding new variables on display, plant height and life habit. In chapter two, I tested the relationship between fruit and seed size, fruit coloration and plant height and quantified the influence of these characters on diversification rates using the MISSE model. Myrtaceae showed wide morphological variation, with large fruits with several small seeds or small fruits with few small seeds. This heterogeneity of functional attributes cannot explain the high speciation rates found in the Myrteae tribe, indicating that other abiotic and biotic factors shape the current diversity of species. In Chapter 3, I tested the visual-attractiveness hypothesis, which predicts that fruits at an intermediate stage of ripeness and with conspicuous coloration increase the attractiveness of the canopy and have the capacity to attract new species.