Frugivores morphological and chemical interaction niches relationship: It is not what it looks like

ROJAS TN; RUGGERA RA; BLENDINGER PG

Corbet

Simposio; 7th Frugivores and Seed Dispersers Symposium; 2020

Fruit traits usage by frugivores could direct the evolution of particular combination of fruit traits. While frugivores use morphological and chemical fruit traits as cues to make foraging decisions, it is known that both types of traits are barely related in fruits. Interaction niches (INs), or the multivariate space constructed with interaction partners? traits, is a promising tool to test the relationship strength between fruit traits in the diet. To understand how are morphological and chemical IN relate, we constructed IN for morphological and chemical traits using seed-dispersal networks. We i)estimated the relationship between INs via co-inertia analysis and ii)originality (distance from community centroid) and uniqueness (distance to closest neighbor) for each niche centroid to evaluate the relationship of these measures with specialization (d?) and number of interaction partners; iii)we fitted a GLM to test the relation between estimated dispersion of INs with specialization (d?) and number of partners; iv)we used two null models to evaluate departures from frequency of interactions and number of species used by frugivores. We found an important difference when comparing coinertia of morphological and chemical fruit traits (RV=0.3) with coinertia of morphological and chemical frugivores INs (RV=0.7). Chemical and morphological originality were negatively related with number of interaction partners (b=-0.5; b=-0.4, respectively). INs dispersions were positively related with the number of interaction partners (b=0.6, morphological; b=0.6 chemical). Null models comparisons suggest that frequency of interactions and number of partners are the main shaper of observed pattern. Our results shown that the number partners determines the amplitude and position of centroid of the IN and that fruit trait relationships are unlikely to be strengthen by frugivore foraging decisions. In summary, frugivores consume a combination of fruit traits similar to the community centroid, this usage of different food elements could fit with the diet complementarity mechanism.