There are two main types of reproduction: asexual reproduction which involves one parent and results in offspring that are genetically identical; and sexual reproduction which involves two parents and increases genetic diversity in offspring through meiosis and fertilization. Some common asexual reproduction methods include binary fission in prokaryotes, fragmentation and regeneration in fungi and plants, and budding in yeasts and hydras. Sexual reproduction, the primary method for most complex organisms, requires pollination to deliver pollen for fertilization of flowering plants.