Fleshy-fruit traits and seed dispersers: which traits define syndromes?

ROJAS, TOBIAS NICOLAS; ZAMPINI, IRIS CATIANA; ISLA, MARÍA INÉS; BLENDINGER, PEDRO G

ANNALS OF BOTANY

OXFORD UNIV PRESS

Año: 2022 vol. 129 p. 831 - 838

0305-7364

Background and AimsFruit traits and their interrelations can affect foraging choices by frugivores, and hence, the probability of mutualistic interactions. Certain combinations of fruit traits that determine the interaction with specific seed dispersers are known as dispersal syndromes. The dispersal syndrome hypothesis (DSH) states that seed dispersers influence the combination of fruit traits found in fruits. Therefore, fruit traits can predict the type of dispersers with which plant species interact. Here, we analysed whether fruit traits? relationships can be explained by DSH. To do so, we estimated the interrelation between morphological, chemical and display groups of fruit traits. In addition, we tested the importance of each trait-group defining seed dispersal syndromes.MethodsUsing phylogenetically corrected fruit traits? data and fruit-seed disperser networks, we tested the relationships among morphological, chemical and display fruit traits with Pearson?s correlations and phenotypic integration indices. Then, we used perMANOVA to test if the fruit traits involved in the analysis supported seed dispersers? functional types.Key resultsMorphological traits showed strong intra-group relationships, contrasting to chemical and display traits whose intra-group trait relationships were weak or null. Accordingly, only the morphological group of traits supported three broad seed disperser functional types (birds, terrestrial mammals and bats), consistently with the DSH.ConclusionsAltogether, our results give some support to the DSH. Here, the three groups of traits interacted in different ways with seed dispersers? biology. Broad functional types of seed dispersers would adjust fruit consumption to anatomical limitations imposed by fruit morphology. Once this anatomic filter is surpassed, seed dispersers use almost all the range of variation in chemical and display fruit traits. This suggests that the effect of seed dispersers on fruit traits is modulated by hierarchical decisions. First, morphological constraints define which interactions can actually occur; subsequently, display and composition determine fruit preferences.