INVESTIGADORES
LOMASCOLO Silvia Beatriz
congresos y reuniones científicas
Título:
Do frugivores shape the evolution of fruits? A test of the Dispersal Syndrome hypothesis
Autor/es:
LOMÁSCOLO, SILVIA B.; SPERANZA, PABLO; KIMBALL, REBECCA T.
Lugar:
Brisbane
Reunión:
Simposio; IV International Symposium on Frugivory an Seed Dispersal; 2005
Resumen:
The influence of seed dispersers in the evolution of fruiting plants has often been questioned by studies of fruit evolution. Most such studies, however, have failed to take into account the phylogenetic history of the plants under study, which may confound fruit variation due to common ancestry with adaptive variation; have used inefficient means of controlling for phylogenetic history, such as focusing on conservative taxonomic levels; or have ignored traits that are important for fruit recognition by frugivores, such as fruit color. We test the hypothesis that fruit traits evolve in response to the selective pressure of seed dispersers. Under this hypothesis, we predict the existence of two dispersal syndromes, which we define as sets of fruit traits that appear together more often that expected by chance. (1) Mammal Syndrome fruits should be dull-colored and large, because mammals are commonly nocturnal and rely more heavily on olfaction than on visual cues for finding fruits, and because they have teeth, which allows them to eat fruits piecemeal. (2) Bird Syndrome fruits should be brightly colored and small, because birds are mostly diurnal and have acute color vision, and because they lack teeth and commonly swallow fruits whole.  Likelihood ratio (likelihood ratio = 3.053; p-value = 0.044; 1006 simulations) and Correlated Changes (0.002 < p-value < 0.07, depending on parameter combinations) tests performed on a molecular phylogeny of 64 species of Ficus (Moraceae) support the existence of dispersal syndromes, and suggest that seed dispersers may be important in shaping fruit evolution.