Seed dispersal is one of the key phases in the regeneration process of plant populations. It determines the potential area of recruitment and, simultaneously, acts as a template for the subsequent stages of plant growth. Seed dispersal is the most common means for plants to colonize new areas and to avoid sibling competition and natural enemies such as herbivores or pathogens. Seeds can be dispersed by wind, water, gravity and by a wide assemblage of animals (including those that consume fruits and/or seeds as well as those that move seeds via their fur, plumage or feet). By directly dispersing seeds to favourable recruitment sites (Wenny and Levey, 1998) or by virtue of the treatment offered to ingested seeds (Verdú and Traveset, 2004; Traveset et al., 2007), animals actually play an important role as seed dispersers for most (60–80%) plant species (Levey et al., 2002; Dennis et al., 2007). Moreover, seed dispersers are crucial in plantcommunity dynamics in many ecosystems around the globe and contribute to numerous ecosystem services offered by forests, including fruit, wood and non-timber products, carbon sequestration and forest cover – at no cost to humans (Forget et al., 2011). Seed dispersal is currently a very active research area that includes both ecological and evolutionary aspects. Studies have diversified in the last few decades mainly towards the study of landscape ecology (movement patterns), plant genetic diversity and structure (gene flow through pollen and/or seeds), community ecology (e.g. mutualistic interaction networks), dispersal adaptations of both plants and seed dispersers, conservation biology (effects of different types of disturbances such as habitat fragmentation, defaunation and biological invasions) and ecological restoration. Research on seed dispersal has actually shifted from being organism oriented towards being currently more mechanism oriented in order to unravel the mechanistic processes behind seed dispersal (Jordano et al., 2011). Thus, for instance, by means of increasingly precise tools, such as radio or satellite tracking, researchers can now study the movement of animal seed dispersers across habitats (Blake et al., 2012), or even across continents (Kays et al., 2011), and evaluate plant seed dispersal kernels (i.e. the probability density function of the dispersal distance for an individual or population).

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