The life cycle begins with a planktonic planula-like larva produced by sexual reproduction, which later becomes the "sicular zooid" who starts a colony. In "Rhabdopleura", the colonies bear male and female zooids but fertilized eggs are incubated in the female tubarium, and stay there until they become larvae able to swim (after 4–7 days) to settle away to start a new colony. Each larva surrounds itself in a protective cocoon where the metamorphosis to the zooid takes place (7–10 days) and attaches with the posterior part of the body, where the stalk will eventually develop.