Seed dispersal

The sedentary life of adult plants accentuates the critical importance of the short phase during which individual plants move: the dispersal of seeds, a common, widespread and fascinating phenomenon. Ultimately, selective pressures favouring dispersal include inbreeding avoidance, reduction of competition with kin and nonkin and the tracking of establishment opportunities in time and space. Proximately, dispersal mechanisms include nonrandom release from the mother plant, and transport by multiple dispersal vectors not necessarily those inferred from the seed morphology. The resulting patterns, often described by dispersal kernels, typically show a decline in seed deposition with distance from the source and a tail of long-distance dispersal events. Yet, environmental heterogeneity may cause more complex dispersal patterns. Dispersal has important consequences for the fate of individuals, populations, communities and ecosystems, enabling metapopulations and metacommunities to persist and playing a critical role in shaping the evolutionary and plastic response of plants to changing environments.