What is the Difference Between Sessile and Motile?
Sessile organisms stay in one place, whereas motile organisms are mobile. The majority of organisms are motile, but many important organisms, including coral, sponges, barnacles, tunicates, bryozoans, polychaete worms, some bivalves, and most brachiopods. Of course, all land plants are sessile. Some animals have motile larval stages and sessile adult stages, or vice versa. Sessile animals must use passive feeding methods, specifically filter feeding. Sessile plants use photosynthesis for energy in all except rare cases. Sessile animals have evolved a variety of interesting means for getting nutritious bits out of water, where they almost always live: tentacles, filters, and pumps. Motile animals, which are by far the most common and complex, have a much greater number of available means to obtain food, but at the same time, their nutrient requirements are greater. Sessile marine organisms have been extremely common since the dawn of multicellular life. Most of the earliest animals, mak