Types of pollen dispersal units and pollen competition

Abstract

The reproductive structures of algae are dispersed actively by means of flagella, or passively, by means of water currents. Likewise in the most primitive terrestrial plants, dispersal may be active or passive, but as well as water currents, air currents are also exploited (Faegri and van der Pijl 1979). Originally in gymnosperms, but now mainly in angiosperms, animals attracted to the reproductive structures by seduction or deception may be agents of dispersal (Dafiii 1984, Pacini 1992).