Seed and gene dispersal by animals is a non-random process that depends on the frugivore assemblage and how the individual dispersers interact with the environment. Therefore, disentangling the relative importance of multiple factors from population characteristics, microhabitat, and landscape features on seed and gene dispersal processes is important to understand how populations persist in human modified environments.

We aim at understanding how gene dispersal via movement of seeds is generated at local scale depending on microhabitat characteristics, as well as along a fragmentation and defaunation gradient in the Atlantic forest.

The study system comprises the juçara palm Euterpe edulis and its avian dispersers. Euterpe edulis is a paramount food source for several animal species, eaten by more than 20 mammals and 50 species of birds. The abundance of the palm varies immensely across its distribution mainly because of the large scale, uncontrolled, harvesting of the heart of palm, which led to the drastic reduction and local extinction of this palm in many remnants of the Atlantic Rainforest. Likewise, most of the large fruit-eating birds (toucans, toucanets and bellbirds) are functionally extinct from most of the small remnants and heavily defaunated reserves. The ecological roles provided by the different frugivore assemblages across the fragmentation gradient will most likely generate a spatial and genetic signature with unknown consequences for the long term persistence of the palm populations in highly impacted areas.

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The main studies involved in this project are:

• Influence of frugivory and landscape structure on the genetic composition of dispersed seeds: we employed microsatellite markers to characterize maternal progeny in deposition sites and conduct maternity analyses to assign dispersed seeds to neighboring palms. In a multiscale approach, we quantified the direct and indirect contribution of microhabitat characteristics, plant density, avian frugivory, forest cover and other land use types on the genetic diversity of dispersed seeds.

• Spatial pattern of the seed rain generated by avian frugivores: we collected spatial information of dispersed seeds, reproductive palms, and animal-dispersed trees on a permanent 1 ha plot located in an Atlantic Rainforest reserve. We aim at revealing the main patterns of seed deposition using spatially explicit analysis and, in turn, sheding light into the ecological processes responsible for the distribution of one the most important plants in the Atlantic Rainforest.

• Mating system and pollination: we used seeds collected directly from palm trees to conduct progeny analyses and characterize rates of outcrossing and self-fertilization. Our goal is to compare these parameters across fragmented and protected forests to better understand the role of pollination on maintaining genetic diversity in fragments of the Atlantic forest.

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