Plant migration rates and seed dispersal mechanisms

Aim Holocene plant migration rates appear to greatly exceed measured disper sal distances. This is a feature of species with all dispersal mechanisms a nd in all communities. The role of dispersal by large mammalian herbivores is explored as a mechanism that accounts for the observed dispersal rates. Methods A simple model was constructed that took into account herbivore dis persal and how migration rates might vary with herbivore territory size, gu t survival and probability of consumption. Results Even at relatively low probabilities of consumption and gut surviva l, dispersal by animals within large territories could account for observed rates of dispersal in the palaeorecord. Animals with small territory sizes could not produce large enough rates of dispersal. Main conclusions As many modern day grassland plants appear to survive gut passage, endozoochory by large mammalian herbivores could be the main mecha nism for long-distance dispersal of herbaceous species.