Metagenesis is a biological phenomena in which an organism undergoes a series of transformations or life cycle phases in which sexual and asexual reproduction alternate. These modifications may encompass morphological, physiological, and behavioural changes. Jellyfish life cycles are a classic illustration of metamorphosis. Jellyfish have a complex life cycle consisting of polyp and medusa stages. The polyp stage is the asexual stage in which the jellyfish assumes the form of a tiny, tube-like, stationary creature. The polyp reproduces asexually by producing identical clones. The polyp will eventually develop into a medusa, the sexual stage of the jellyfish life cycle. The medusa is the form of jellyfish with which the majority of people are most familiar. Jellyfish reproduce sexually during this phase by releasing eggs and sperm into the sea. The fertilised eggs transform into a larval stage, which finally settles on the ocean floor and gives rise to a new polyp. This cycle of alternating asexual and sexual reproduction is an example of jellyfish metamorphosis. Other organisms that undergo metagenesis include certain cnidarians, flatworms, and algae.