Between the dominant adult medusa stage and the small and inconspicuous larval polyp stage, Aurelia jellyfish undergo the ephyra stage. The common and cosmopolitan moon jelly (A. aurita) is often used as a laboratory experimental and dissection model to illustrate the typical Aurelia life stages. Tiny ephyrae swim free of the sessile scyphistoma polyps. As a dispersal stage, the ephyra allows the jellyfish to spread to potential suitable habitats and prevents the placing of all offspring within one locality where they are subject to changes in environmental conditions and catastrophic events.