A colonial organism is an organism composed of multiple constituent organisms. The organisms can be unicellular, as in the alga Volvox (a coenobium), or multicellular, as in the Portuguese man o' war. The former type may have been the first step toward multicellular organisms.[1] A colonial organism can be distinguished from a conventional colony of independent organisms by the closer association of its component parts into discrete individual superorganisms, and typically by the presence of differentiation into two or more specialized component types. Conversely, a colonial organism can be distinguished from a conventional multicellular organism by the looser association and repeating nature of its component subunits—perhaps with specializations, but still visibly similar. The components can also be recognized as organisms in their own right by comparison with evolutionarily related free-living species. For example, the Portuguese man o' war is a colony of four different types of polyp or related forms. These four types can be readily seen to be analogs of one another (or of immature stages), and also of related free-living cnidarians such as jellyfish.