The idea for this OOS was developed by a working group that was formed during the Seed Dispersal Workshop held at SESYNC in May 2016.
Session Description: Seed dispersal is a poorly understood phenomenon of great conservation importance, since it is both affected by global change and affects the ability of plants to respond to global change. As the single opportunity for plants to move, seed dispersal has an important impact on plant fitness, species distributions, and patterns of biodiversity. However, models that predict extinction risk of species, range shifts, and biodiversity loss rarely incorporate realistic dispersal mechanisms and tend to rely on the mean value of parameters due to the challenges of incorporating processes occurring over multiple scales and in heterogeneous environments. By focusing on the mean population value, variation among individuals or variability caused by complex spatial and temporal dynamics are ignored. This calls for increased efforts to understand individual variation in dispersal and integrate it more explicitly into population and community models involving dispersal. However, the sources, magnitude, and outcomes of intraspecific variation in dispersal are poorly characterized, limiting our understanding of the role of dispersal in mediating the dynamics of communities and their response to global change. The objective of this organized oral session is to synthesize recent research that examines the sources of individual variation in dispersal and its implications for plant fitness, populations, and communities. Speakers will focus on causes of individual variation in dispersal due to intrinsic factors (e.g., seed traits, genetic variation, heterogeneity in vital rates) and due to extrinsic factors (e.g., animal behavior, resource availability, environmental conditions), as well as the consequences of this variation for population persistence, spatial spread, selection on species traits, and the maintenance of diversity. This session includes empirical, statistical, and theoretical advances that link intraspecific trait, environmental, and genetic variation in dispersal to population- and community-level outcomes. The goal is to improve our understanding about the importance of individual variation in dispersal in order to increase our ability to predict the relative role of dispersal for plant populations and communities under changing conditions.